what is a round trip delay

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What is RTT(Round Trip Time)?

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RTT (Round Trip Time) also called round-trip delay is a crucial tool in determining the health of a network. It is the time between a request for data and the display of that data. It is the duration measured in milliseconds. 

RTT can be analyzed and determined by pinging a certain address. It refers to the time taken by a network request to reach a destination and to revert back to the original source. In this scenario, the source is the computer and the destination is a system that captures the arriving signal and reverts it back. 

RTT(Round Trip Time) Measurement

What Are Common Factors that Affect RTT?

There are certain factors that can bring huge changes in the value of RTT. These are enlisted below:

• Distance: It is the length in which a signal travels for a request to reach the server and for a response to reach the browser,
• Transmission medium: The medium which is used to route a signal, which helps in faster transfer of request is transmitted.
• Network hops: It is the time that servers take to process a signal, on increasing the number of hops, RTT will also increase.
• Traffic levels: Round Trip Time generally increases when a network is having huge traffic which results in that, for low traffic RTT will also be less.
• Server response time: It is the time taken by a server to respond to a request which basically depends on the capacity of handling requests and also sometimes on the nature of the request.

Applications of RTT

Round Trip Time refers to a wide variety of transmissions such as wireless Internet transmissions and satellite transmissions. In Internet transmissions, RTT may be identified by using the ping command. In satellite transmissions, RTT can be calculated by making use of the Jacobson/Karels algorithm.  

Advantages of RTT

Calculation of RTT is advantageous because:

• It allows users and operators to identify how long a signal will take to complete the transmission.
• It also determines how fast a network can work and the reliability of the network.

Example: Let us assume there are two users, one of which wants to contact the other one. One of them is located in California while the other one is situated in Germany. When the one in California makes the request, the network traffic is transferred across many routers before reaching the server located in Germany. Once the request reverts back to California, a rough estimation of the time taken for this transmission could be made. This time taken by the transmitted request is referred to as RTT. The Round Trip Time is a mere estimate. The path between the two locations can change as the passage and network congestion can come into play, affecting the total period of transmission. 

How Does Round-Trip Time Work?

Consider a topology where an appliance named “Exinda” is located between the client and the server. The diagram shown below depicts how the concept of RTT works: 

RTT Calculation

  For the calculation of Average RTT, RTTS for server and client needs to be calculated separately. The performed calculations are shown below:

Server RTT: RTT1 = T2 – T1 RTT2 = T5 – T4

Client RTT: RTT3 = T3 – T2 RTT4 = T7 – T6 

Average RTT: Avg Server RTT = (RTTs1 + RTTs2) / 2 Avg Client RTT = (RTTc1 + RTTc2) / 2 Avg Total RTT = Avg Server RTT + Avg Client RTT 

You can refer to the Program to calculate RTT for more details.

Measures To Reduce RTT

 A significant reduction in RTT can be made using Content Delivery Network (CDN) . A CDN refers to a network of various servers, each acquiring a copy of the content on a particular website. It addresses the factors affecting RTT in the enlisted ways:

• Points of Presence (PoP)
• Web caching
• Load distribution
• Scalability
• Tier 1 access 

CDN has been largely successful in reducing the value of RTT and due to this, a decrease in RTT by 50% is achievable.

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Round trip time (rtt), what is round trip time.

Round-trip time (RTT) is the duration, measured in milliseconds, from when a browser sends a request to when it receives a response from a server. It’s a key performance metric for web applications and one of the main factors, along with Time to First Byte (TTFB), when measuring  page load time  and  network latency .

Using a Ping to Measure Round Trip Time

RTT is typically measured using a ping — a command-line tool that bounces a request off a server and calculates the time taken to reach a user device. Actual RTT may be higher than that measured by the ping due to server throttling and network congestion.

Example of a ping to google.com

Factors Influencing RTT

Actual round trip time can be influenced by:

• Distance  – The length a signal has to travel correlates with the time taken for a request to reach a server and a response to reach a browser.
• Transmission medium  – The medium used to route a signal (e.g., copper wire, fiber optic cables) can impact how quickly a request is received by a server and routed back to a user.
• Number of network hops  – Intermediate routers or servers take time to process a signal, increasing RTT. The more hops a signal has to travel through, the higher the RTT.
• Traffic levels  – RTT typically increases when a network is congested with high levels of traffic. Conversely, low traffic times can result in decreased RTT.
• Server response time  – The time taken for a target server to respond to a request depends on its processing capacity, the number of requests being handled and the nature of the request (i.e., how much server-side work is required). A longer server response time increases RTT.

See how Imperva CDN can help you with website performance.

Reducing RTT Using a CDN

A CDN is a network of strategically placed servers, each holding a copy of a website’s content. It’s able to address the factors influencing RTT in the following ways:

• Points of Presence (PoPs)  – A CDN maintains a network of geographically dispersed PoPs—data centers, each containing cached copies of site content, which are responsible for communicating with site visitors in their vicinity. They reduce the distance a signal has to travel and the number of network hops needed to reach a server.
• Web caching  – A CDN  caches  HTML, media, and even dynamically generated content on a PoP in a user’s geographical vicinity. In many cases, a user’s request can be addressed by a local PoP and does not need to travel to an origin server, thereby reducing RTT.
• Load distribution  – During high traffic times, CDNs route requests through backup servers with lower network congestion, speeding up server response time and reducing RTT.
• Scalability  – A CDN service operates in the cloud, enabling high scalability and the ability to process a near limitless number of user requests. This eliminates the possibility of server side bottlenecks.

Using tier 1 access to reduce network hops

One of the original issues CDNs were designed to solve was how to reduce round trip time. By addressing the points outlined above, they have been largely successful, and it’s now reasonable to expect a decrease in your RTT of 50% or more after onboarding a CDN service.

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December 12, 2023

What is Round-trip Time and How Does it Relate to Network Latency?

Tsahi Levent-Levi, Senior Director, Product

Round-trip time (RTT) is an important metric that can indicate the quality of communications available between two end-points. It’s a metric that our team often discusses with customers because it directly relates to the service quality experienced. RTT can be impacted by a range of design decisions, especially concerning network topology. However, there is some confusion around what exactly RTT is, how it relates to latency, how it can impact your service, and how you can improve it.

What is Round-trip Time?

One of our most viewed dashboard metrics in our Cyara testRTC product suite is RTT. This is the time it takes for a packet to go from the sending endpoint to the receiving endpoint and back. There are many factors that affect RTT, including propagation delay, processing delay, queuing delay, and encoding delay. These factors are generally constant for a given pair of communicating endpoints. Additionally, network congestion can add a dynamic component to RTT.

Propagation delay is the network distance between the two endpoints. It is the route taken by the data across the various networks, through different network switches and routers to get from the sending endpoint to the receiving endpoint. Sometimes, this may be aligned with geographical distances and sometimes it may not. Propagation delay is usually the dominant component in RTT. It ranges from a few milliseconds to hundreds of milliseconds, depending on whether the endpoints are separated by just a few kilometers or by an entire ocean.

The remaining components (processing, queuing, and encoding delays) can vary by the number of nodes in the network connecting endpoints. When only a few router hops separate the endpoints, these factors are insignificant. However, the more hops, the higher the delay, since each network node needs to receive, process and route all the data towards the next hop, adding its own milliseconds of delay to the total RTT calculation.

Impact of Network Topology

In real-time communications, we must consider the impact of network topology on RTT. Any infrastructure-based topology introduces incremental delays when compared with a peer-to-peer connection. When media is anchored by a multipoint control unit MCU , SFU , or TURN server, additional processing, queuing and encoding delays occur. But, more importantly, an infrastructure topology can add significant propagation delay depending on where the server is located relative to the endpoints.

Figure 1: Infrastructure Topology

Hairpinning occurs when media is anchored in a location that is geographically remote from an endpoint, this adds significant propagation delay, when compared to a peer connection. This is why the placement of infrastructure can be critical to delivering low RTT and a high-quality user experience. The further the media server is from the sending and receiving endpoints, the higher the RTT value and the lower the service quality.

Figure 2: The media server is located further away than necessary from the sending and receiving endpoints, resulting in a high round-trip time.

Figure 3: The media server is located between the sending and receiving endpoints, resulting in a lower round-trip time.

Clearing Up a Few Misconceptions

RTT and ping time are often considered synonymous. But while ping time may provide a good estimate of RTT, it is different. This is because most ping tests are executed within the transport protocol using internet control messaging protocol (ICMP) packets. In contrast, RTT is measured at the application layer and includes the additional processing delay produced by higher level protocols and applications (e.g. HTTPS). In WebRTC, RTT on the media streams is calculated by looking at the secure real-time transport protocol (SRTP) packets themselves. This provides the closest measure to what the actual media in a session feels like in terms of RTT.

Network latency is closely related, but different from RTT. Latency is the time it takes for a packet to go from the sending endpoint to the receiving endpoint. Many factors affect the latency of a service, including:

• Network congestion
• Packet loss and jitter
• Traffic prioritization
• Server load
• Codecs and encryption

Therefore, latency is not explicitly equal to half of RTT, because delays may be asymmetrical between any two given endpoints. For example, RTT includes processing delay at the echoing endpoint.

How Does RTT Affect Your Real-time Communications Service?

As a rule of thumb, the lower the RTT, the higher the media quality for that session is. Our focus is on ensuring the delivery of live, highly interactive services and conversations. Doing that requires a low delay from the time a user speaks until the intended recipients hear the spoken words.

At Cyara, we’ve made RTT a central focus in all of our WebRTC services. We ensure it is available to you in both aggregate form (in highlight dashboards) as well as in drill down analysis charts where you can analyze RTT over time.

Read more about: Cyara testRTC , Latency , Round-Trip Time (RTT) , Web Real-Time Communication (WebRTC) , WebRTC Monitoring

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Written by Vasilena Markova • September 27, 2023 • 12:58 pm • Internet

Round-Trip Time (RTT): What It Is and Why It Matters

Round-Trip Time (RTT) is a fundamental metric in the context of network performance, measuring the time it takes for data packets to complete a round trip from source to destination and back. Often expressed in milliseconds (ms), RTT serves as a critical indicator for evaluating the efficiency and reliability of network connections. In today’s article, we dive into the concept of RTT, exploring how it works, why it matters in our digital lives, the factors that influence it, and strategies to enhance it. Whether you’re a casual internet user seeking a smoother online experience or a network administrator aiming to optimize your digital infrastructure, understanding this metric is critical in today’s interconnected world.

Table of Contents

What is Round-Trip Time (RTT)?

Round-Trip Time is a network performance metric representing the time it takes for a data packet to travel from the source to the destination and back to the source. It is often measured in milliseconds (ms) and is a crucial parameter for determining the quality and efficiency of network connections.

To understand the concept of RTT, imagine sending a letter to a friend through the postal service. The time it takes for the letter to reach your friend and for your friend to send a reply back to you forms the Round-Trip Time for your communication. Similarly, in computer networks, data packets are like those letters, and RTT represents the time it takes for them to complete a round trip.

How Does it Work?

The concept of RTT can be best understood by considering the journey of data packets across a network. When you request information from a web server, for example, your device sends out a data packet holding your request. This packet travels through various network devices in between, such as routers and switches, before reaching the destination server. Once the server processes your request and prepares a response, it sends a data packet back to your device.

Round-Trip Time is determined by the time it takes for this data packet to travel from your device to the server (the outbound trip) and then back from the server to your device (the inbound trip). The total RTT is the sum of these two one-way trips.

Let’s break down the journey of a data packet into several steps so you can better understand the RTT:

• Sending the Packet: You initiate an action on your device that requires data transmission. For example, this could be sending an email, loading a webpage, or making a video call.
• Packet Travel: The data packet travels from your device to a server, typically passing through multiple network nodes and routers along the way. These middle points play a significant role in determining the RTT.
• Processing Time: The server receives the packet, processes the request, and sends a response back to your device. This processing time at both ends also contributes to the Round-Trip Time.
• Return Journey: The response packet makes its way back to your device through the same network infrastructure, facing potential delays on the route.
• Calculation: It is calculated by adding up the time taken for the packet to travel from your device to the server (the outbound trip) and the time it takes for the response to return (the inbound trip).

Why does it matter?

At first look, Round-Trip Time (RTT) might seem like technical terminology, but its importance extends to various aspects of our digital lives. It matters for many reasons, which include the following:

• User Experience

For everyday internet users, RTT influences the sensed speed and responsiveness of online activities. Low Round-Trip Time values lead to a seamless experience, while high RTT can result in frustrating delays and lag during tasks like video streaming, online gaming, or live chats.

• Network Efficiency

Network administrators and service providers closely monitor RTT to assess network performance and troubleshoot issues. By identifying bottlenecks and areas with high RTT, they can optimize their infrastructure for better efficiency.

• Real-Time Applications

Applications that rely on real-time data transmission, such as VoIP calls, video conferencing, and online gaming, are highly sensitive to RTT. Low RTT is crucial for smooth, interruption-free interactions.

In cybersecurity, Round-Trip Time plays a role in detecting network anomalies and potential threats. Unusually high RTT values can be a sign of malicious activity or network congestion.

Factors Affecting Round-Trip Time (RTT)

Several factors can influence the metric, both positively and negatively. Therefore, understanding these factors is crucial, and it could be very beneficial for optimizing network performance:

• Distance: The physical distance between the source and destination plays a significant role. Longer distances result in higher RTT due to the time it takes for data to travel the network.
• Network Congestion: When a network experiences high volumes of traffic or congestion, data packets may be delayed as they wait for their turn to be processed. As a result, it can lead to packet delays and increased RTT.
• Routing: The path a packet takes through the network can significantly affect RTT. Efficient routing algorithms can reduce the time, while not-so-optimal routing choices can increase it.
• Packet Loss: Packet loss during transmission can occur due to various reasons, such as network errors or congestion. When lost, packets need to be retransmitted, which can seriously affect the Round-Trip Time.
• Transmission Medium: It is a critical factor influencing RTT, and its characteristics can vary widely based on the specific medium being used. Fiber optic cables generally offer low RTT due to the speed of light in the medium and low signal loss. In contrast, wireless mediums can introduce variable delays depending on environmental factors and network conditions.

How to improve it?

Improving Round-Trip Time (RTT) is a critical goal for network administrators and service providers looking to enhance user experiences and optimize their digital operations. While some factors affecting it are beyond our control, there are strategies and practices to optimize Round-Trip Time for a smoother online experience:

• Optimize Routing: Network administrators can optimize routing to reduce the number of hops data packets take to reach their destination. This can be achieved through efficient routing protocols and load balancing .
• Optimize Network Infrastructure: For businesses, investing in efficient network infrastructure, including high-performance routers and switches, can reduce internal network delays and improve RTT.
• Upgrade Hardware and Software: Keeping networking equipment and software up-to-date ensures that you benefit from the latest technologies and optimizations that can decrease RTT.
• Implement Caching: Caching frequently requested data closer to end-users can dramatically reduce the need for data to travel long distances. The result really helps with lowering RTT.
• Monitor and Troubleshoot: Regularly monitor your network for signs of congestion or packet loss. If issues arise, take steps to troubleshoot and resolve them promptly.

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Round-Trip Time (RTT) is the silent force that shapes our online experiences. From the seamless loading of web pages to the quality of our video calls, RTT plays a pivotal role in ensuring that digital interactions happen at the speed of thought. As we continue to rely on the Internet for work, entertainment, and communication, understanding and optimizing this metric will be crucial for both end-users and network administrators. By reducing it through strategies, we can have a faster, more responsive digital world where our online activities are limited only by our imagination, not by lag.

Hello! My name is Vasilena Markova. I am a Marketing Specialist at ClouDNS. I have a Bachelor’s Degree in Business Economics and am studying for my Master’s Degree in Cybersecurity Management. As a digital marketing enthusiast, I enjoy writing and expressing my interests. I am passionate about sharing knowledge, tips, and tricks to help others build a secure online presence. My absolute favorite thing to do is to travel and explore different cultures!

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Understanding latency

Latency is the time it takes for a packet of data to travel from source to a destination. In terms of performance optimization, it's important to optimize to reduce causes of latency and to test site performance emulating high latency to optimize for users with lousy connections. This article explains what latency is, how it impacts performance, how to measure latency, and how to reduce it.

What is Latency?

Latency is generally considered to be the amount of time it takes from when a request is made by the user to the time it takes for the response to get back to that user. On a first request, for the first 14Kb bytes, latency is longer because it includes a DNS lookup, a TCP handshake , the secure TLS negotiation. Subsequent requests will have less latency because the connection to the server is already set.

Latency describes the amount of delay on a network or Internet connection. Low latency implies that there are no or almost no delays. High latency implies that there are many delays. One of the main aims of improving performance is to reduce latency.

The latency associated with a single asset, especially a basic HTML page, may seem trivial. But websites generally involve multiple requests: the HTML includes requests for multiple CSS, scripts, and media files. The greater the number and size of these requests, the greater the impact of high latency on user experience.

On a connection with low latency, requested resources will appear almost immediately. On a connection with high latency, there will be a discernible delay between the time that a request is sent, and the resources are returned. We can determine the amount of latency by measuring the speed with which the data moves from one network location to another.

Latency can be measured one way, for example, the amount of time it takes to send a request for resources, or the length of the entire round-trip from the browser's request for a resource to the moment when the requested resource arrives at the browser.

Network throttling

To emulate the latency of a low bandwidth network, you can use developer tools and switch to a lower end network connection.

In the developer tools, under the network table, you can switch the throttling option to 2G, 3G, etc. Different browser developer tools have different preset options, the characteristics emulated include download speed, upload speed, and minimum latency, or the minimum amount of time it takes to send a packet of data. The approximate values of some presets include:

Network Timings

Also, on the network tab, you can see how long each request took to complete. We can look at how long a 267.5Kb SVG image asset took to download.

When a request is in a queue, waiting for a network connection it is considered blocked . Blocking happens when there are too many simultaneous connections made to a single server over HTTP. If all connections are in use, the browser can't download more resources until a connection is released, meaning those requests and resources are blocked.

DNS resolution is the time it took to do the DNS lookup. The greater the number of hostnames , the more DNS lookups need to be done.

Connecting is the time it takes for a TCP handshake to complete. Like DNS, the greater the number of server connections needed, the more time is spent creating server connections.

The TLS handshake is how long it took to set up a secure connection. While a TLS handshake does take longer to connect than an insecure connection, the additional time needed for a secure connection is worth it.

Sending is the time taken to send the HTTP request to the server.

Waiting is disk latency, the time it took for the server to complete its response. Disk latency used to be the main area of performance concern. However, server performance has improved as computer memory, or CPU, has improved. Depending on the complexity of what is needed from the server, this can still be an issue.

Receiving is the time it takes to download the asset. The receiving time is determined by a combination of the network capacity and the asset file size. If the image been cached, this would have been nearly instantaneous. Had we throttled, receiving could have been 43 seconds!

Measuring latency

Network latency is the time it takes for a data request to get from the computer making the request, to the computer responding. Including the time it takes for a byte of data to make it from the responding computer back to the requesting computer. It is generally measured as a round trip delay.

Disk latency is the time it takes from the moment a computer, usually a server, receives a request, to the time the computer returns the response.

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All You Need to Know About Round-Trip Time

What exactly is rtt .

Round-trip time (RTT) is a networking metric that measures in milliseconds the time it takes for a data packet to be sent and the time it takes for an acknowledgment of that signal to be received . The propagation times for the paths between the two communication endpoints are included in this time delay. As you can imagine, a CDN’s primary goal is to reduce it. Also, latency improvements can be measured by reducing RTT.

Ping, Latency and now the RTT. It brings out this question: Are they the same?

The ping utility, which is found on almost every computer, is a method of estimating round-trip time. Ping tests, on the one hand, are typically performed within a transport protocol that employs ICMP packets. Network latency, on the other hand, is closely related, but it is not the same as RTT. Latency is the amount of time it takes for a data packet to travel from one endpoint to the other. The processing delay at the echo endpoint is included in Round Trip Time.

What is a good RTT?

Every application will have its own set of requirements, and it is nearly impossible to give a specific time frame. What is tolerable in one use may be intolerable in another. Still, we can approximately say that your users should have an RTT of at least 95ms for normal application usage and a maximum of 190ms before your application degrades the quality of your service.

What are the most prevalent factors influencing Round Trip Time?

Potential elements that may have an impact on RTT are distance, local area network traffic and response time.

• Distance : CDN optimized connections can minimize the number of hops necessary to reach a destination; nonetheless, network connectivity is limited by distance.
• LAN Traffic : Because of the quantity of traffic on the local area network, connections might be barriers before they ever reach the wider Internet network.
• Response Time: The time it takes a target server to reply to a request is determined by its processing capability, the number of requests processed, and the type of the request. As a result, a longer server response time raises RTT.

Reducing Round Trip Time with a Content Delivery Network (CDN)

A content delivery network (CDN) is a network of strategically positioned servers, each carrying a duplicate of a website’s content. It is capable of addressing the following elements that impact RTT: 

First of all, each PoP that contains cached copies of site content is responsible for interacting with site users in their immediate location. There are less signal transmission distance and network hops to reach a server. Also, on a PoP in the user’s geographic area, CDNs cache HTML, media, and even dynamically generated content (DGC). Users’ requests can be handled by a local PoP, decreasing RTT.

Moreover, TLS 1.3 decreases web page latency by shortening the RTT required to connect the client and server. TLS 1.3 has been updated with new digital signature algorithms. With 1.3, the first support for 1-RTT Handshake and 0-RTT were added. This feature is provided to our customers free of charge on the Medianova CDN platform.

Last but not least, another impact worth mentioning is speeding up server response times and reducing RTT by using Anycast. In most cases, Anycast directs incoming traffic to the nearest data center with less network congestion during peak traffic periods.

At Medianova, we focus on all the ways to accelerate, enhance and secure your content delivery. Get in touch with us to learn more about how Medianova can help you deliver the best online experiences. 

What Is Wi-Fi RTT?

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Have you ever noticed that your smartphone can pinpoint your location with far greater accuracy when you’re outside than when you’re indoors? That’s because GPS accuracy has been steadily improving over the years, largely thanks to changes in satellite and receiver hardware. Besides, one or two meters here and there doesn’t mean much when walking down the street.

However, one or two meters indoors can be the difference between the living room and the bathroom or the meat aisle and the fresh produce section.

Currently, smartphones are able to achieve indoor accuracy of slightly less than 10 meters, which is insufficient for anything else apart from very course location tracking. Fortunately, there’s already technology available that will improve indoor accuracy to the one-meter level, and its name is Wi-Fi Round-Trip-Time, or Wi-Fi RTT for short.

What Is RTT?

Wi-Fi RTT is a feature added to the IEEE 802.11 protocol by the Task Group mc (TGmc) of the IEEE 802.11 Working Group, sometimes referred to as IEEE 802.11mc . The purpose of Wi-Fi RTT is to allow devices to measure the distance to nearby Wi-Fi routers and determine their indoor location with a precision of 1-2 meters.

If you’ve ever used Google’s “Find My Device” service to see the last known position of your smartphone on a map only to see a marker vaguely placed at our house, you can probably already see where the need for Wi-Fi RTT comes from.

Unsurprisingly, Google has added support for the technology to Android 9 Pie, and it has promised to add support for Wi-Fi RTT to the Google Wi-Fi mesh router. Other companies are likely to follow suit because Wi-Fi RTT could be a game-changer when it comes to home automation.

Just imagine waking up in the morning, walking into the kitchen, and hearing your coffee maker automatically turn on because your smartphone is aware of your exact location and programmed to tell your coffee maker to make you a cup of coffee when you enter your kitchen.

But Wi-Fi RTT isn’t just for individual smartphone users. Companies and organizations will be able to help their visitors get to where they want to go in a way that’s extremely convenient, modern, and potentially highly interactive and even monetizable. A shopping mall, for example, could display nearest discounts along with navigational information.

How Does Wi-Fi RTT Work?

The key to understanding how Wi-Fi RTT works is round-trip time, sometimes referred to as round-trip delay. Here’s one concise RTT definition: network round-trip time is the length of time it takes for a signal to be sent plus the length of time it takes for an acknowledgment of that signal to be received.

Thanks to Wi-Fi RTT, smartphones will soon be able to use time-of-flight instead of signal strength to figure out how far away they are from Wi-Fi routers. With a single Wi-Fi router, you get the distance. With three or more Wi-Fi routers, trilateration (the process of determining absolute or relative locations of points by measurement of distances) with an accuracy of one to two meters becomes possible.

The users of Android P smartphones don’t have to be connected to any Wi-Fi routers for Wi-Fi RTT to work because only the smartphone is used to determine distance. Google has tied Wi-Fi RTT into Android’s existing location system to protect the privacy of its users. What’s more, Wi-Fi RTT transactions require the used MAC address to be randomized as a protection against the location tracking of individual smartphone users by unauthorized third-parties.

Which Devices Support Wi-Fi RTT?

From the technical standpoint, virtually any modern 802.11ac router could support Wi-Fi RTT with a firmware upgrade. The unfortunate reality is that the manufacturers of wireless routers would much rather come up with brand-new products than many firmware upgrades for the existing ones simply because companies don’t make money out of firmware upgrades.

As we’ve already mentioned, Google has promised to add support for Wi-Fi RTT to the Google Wi-Fi mesh router, but the company has yet to act on its promise. So far, the only Wi-Fi RTT network certified products are:

To check Wi-Fi RTT support, you need to look up whether your Wi-Fi router comes with any of these Wi-Fi RTT network certified products. One such router is the Linux-driven Compulab WILD Wi-Fi router , which has the Intel Dual Band Wireless-AC 8260card.

According to Compulab, one WILD router can track other WILD routers with an accuracy of under 0.5 meters, making it useful for applications in retail, health care, transportation, logistics, manufacturing, smart buildings, and entertainment, just to give a few examples.

If you decide to purchase any Wi-Fi RTT-compatible router, it’s important that you use a professional Wi-Fi analysis tool like NetSpot to find the best spot for it and continuously monitor various aspects of your Wi-Fi network to achieve optimal performance.

NetSpot works with all with 802.11a/b/g/n/ac/ax wireless network adapters and supports 2.4 GHz and 5 GHz frequency bands at 20/40/80/160 MHz channels. You can download it for free and run it on a MacBook (macOS 10.10+) or any laptop (Windows 7/8/10/11).

Wi-Fi RTT is about to make indoor location tracking far more accurate than it is today. So far, there are only a few Wi-Fi RTT network certified products out there, but this will likely change very quickly considering that Google has already added support for Wi-Fi RTT in Android 9.

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Latency vs Round Trip Time: Understanding the Differences

As someone who works in the technology industry, I often come across the terms “latency” and “round trip time” (RTT). While both terms are related to network performance, they are not interchangeable.

Understanding latency and RTT is crucial for troubleshooting network issues and improving network performance. In this article, I will explain latency and RTT and how they differ.

Table of Contents

What is Latency?

Latency refers to the time it takes for a packet of data to travel from its source to its destination . It’s the measure of how long it takes for a packet to travel from one point to another. Latency is often measured in milliseconds (ms), and the lower the latency, the better the network performance.

Many factors can affect latency, including the distance between the source and destination, the number of hops the packet must take, and the network’s speed. For example, if you’re sending a packet from New York to Los Angeles, it will take longer for the packet to travel that distance than if you’re sending it from New York to Boston.

Similarly, if the packet must pass through multiple routers or switches, it will take longer to reach its destination than if it only had to pass through one.

What is Round Trip Time?

Round trip time, or RTT, measures the time it takes for a packet to travel from its source to its destination and then back again . It’s time it takes for a packet to make a round trip. RTT is also measured in milliseconds (ms), and like latency, the lower the RTT, the better the network performance.

RTT is affected by the same factors that affect latency, including distance, number of hops, and network speed. However, RTT also considers the time it takes for the destination to process the packet and send a response.

For example, if you’re sending a packet to a server that’s busy processing other requests, it will take longer for the server to respond, and thus, the RTT will be higher.

Differences between Latency and RTT

The main difference between latency and RTT is that latency only measures the time it takes for a packet to travel from its source to its destination, while RTT measures the time it takes for a packet to make a round trip.

Latency measures the time it takes for a packet to travel from one point to another. It’s the measure of one-way delay. RTT measures the time it takes for a packet to travel from its source to its destination and back again. It’s the measure of two-way delay.

Another important difference is that while latency only measures the time it takes for a packet to travel from one point to another, RTT considers the time it takes for the destination to process the packet and send a response.

For example, if you’re trying to access a website, the latency will measure the time it takes for the packet to travel from your computer to the server hosting it. The RTT will measure the time it takes for the packet to travel from your computer to the server hosting the website and back to the webpage.

Latency and RTT are network performance measures, but they measure differently. Latency measures the time it takes for a packet to travel from one point to another, while RTT measures the time it takes for a packet to make a round trip.

Understanding the difference between these two terms is crucial for troubleshooting network issues and improving network performance.

How to Measure Latency and RTT?

Several tools and methods can be used to measure latency and RTT. One of the most common tools is the ping command. The ping command sends a packet to a specified destination and measures the time it takes for the packet to return. The ping command can be used to measure both latency and RTT.

Another tool that can be used to measure latency and RTT is traceroute. Traceroute works by sending packets to a specified destination and measuring the time it takes for each packet to reach each hop along the way.

It also provides information about each hop, such as IP address and hostname. This tool is useful for identifying the source of network issues, as it can show where packets are getting delayed.

There are also specialized tools and services, such as Speedtest and Cloudping, that can be used to measure network performance. These tools typically provide more detailed information about network performance, such as upload and download speeds, and can be used to compare network performance between different locations and providers.

What are Some Ways to Improve Latency and RTT?

There are several ways to improve latency and RTT, but it’s important to understand that not all solutions will work in all situations. The most effective solutions will depend on the specific network and the root cause of the latency or RTT issues.

One common solution is to upgrade network hardware, such as routers and switches . This can improve network speed and reduce the number of hops packets must take, thereby reducing latency and RTT.

Another solution is to optimize network configurations. This can include optimizing routing protocols and adjusting packet size. This can help to improve network efficiency and reduce the number of hops packets must take, thereby reducing latency and RTT.

Optimizing network software and applications can also help to improve network performance. This can include optimizing web servers, databases, and other applications to reduce the time it takes for the destination to process packets and send a response.

Finally, it’s also essential to consider the physical location of network devices. For example, if devices are located in a poorly ventilated area, they may overheat and become less efficient, resulting in increased latency and RTT.

By moving the devices to a cooler location or adding additional cooling, the devices will be able to run more efficiently, which can help to improve network performance.

Latency and RTT are both important network performance measures, but they measure different things. Latency measures the time it takes for a packet to travel from one point to another, while RTT measures the time it takes for a packet to make a round trip.

Understanding these two terms’ differences is crucial for troubleshooting network issues and improving network performance. Several tools and methods can be used to measure latency and RTT.

There are several ways to improve network performance, such as upgrading network hardware, optimizing network configurations, optimizing network software and applications, and considering the physical location of network devices.

Frequently Asked Questions

Why is it important to understand the difference between latency and rtt.

Understanding latency and RTT is crucial for troubleshooting network issues and improving network performance. Latency and RTT are network performance measures, but they measure differently.

By understanding the difference between these two terms, you can better understand where network issues are occurring and implement solutions to improve performance.

Can latency and RTT be reduced to zero?

It’s impossible to reduce latency and RTT to zero, as there will always be some delay due to the physical distance between the source and destination.

However, latency and RTT can be minimized through various methods such as upgrading network hardware, optimizing network configurations, and reducing the number of hops packets must take.

Can you give an example of a situation where latency is more important than RTT?

One example of a situation where latency is more critical than RTT is in online gaming . When playing a game online, players expect a low latency to ensure that their actions are responsive and they have the best gaming experience.

In this case, it’s more important to minimize the time it takes for a packet to travel from the player’s computer to the game server than to measure the time it takes for a packet to make a round trip.

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Tim has always been obsessed with computers his whole life. After working for 25 years in the computer and electronics field, he now enjoys writing about computers to help others. Most of his time is spent in front of his computer or other technology to continue to learn more. He likes to try new things and keep up with the latest industry trends so he can share them with others.

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September 1, 2020

What is Network Round-Trip Delay?

Network Round Trip Delay Impact Application Performance?

Round trip delay (RTD), a.k.a. Round trip time (RTT), or ping time, is the duration of time it takes for a signal to reach its destination across a network and then for an acknowledgment signal to return to the originator. This measurement includes all delays caused by routing, transmission medium, and network traffic. The return signal does not have to follow the same path that the initial signal took.

How do you measure Network Round-Trip Delay?

Using standard ping tools found on most computers, network round trip delay can be tested easily from the command line. The ping time or ping rate is typically measured in milliseconds (ms). The standard ping is measured for either Round Trip Time (RTT) or Time to First Byte (TTFB). RTT is the total time it takes for a data packet to go from the client and return from the server, and it is the standard reporting measurement. TTFB is the time it takes for the server to get the first byte of client data, and should be half the time as RTT on the same path.

Application Performance and Network Round Trip Delay

Impact of RTT on Application Performance

Round trip delay is closely related to network latency. RTD is the measure on which network latency and network jitter are calculated, and because of this, it shares the same impacts that latency and jitter have on quality of service (QoS). As RTD increases so does network latency, and as the variance between RTDs in a transmission increases so does the jitter.

What are the factors that impact Round-Trip Delay (RTD)?

• Transmission Medium—Network traffic speed is limited by the physical connections that it travels through. Because a signal can only travel as fast as the medium of transport allows, understanding the slowest and fastest mediums along a signals route becomes crucial in controlling RTD. For example, fiber optic cable is roughly 100x faster than coax cable, and over greater distances mostly fiber optic is used. However, leading into most homes, some variation of metal cable is used for the internet. This means, at these points of medium change, we can expect there to be transmission delays as signal slows down to when passing from fiber optic to travel across the copper medium. Further, inside the home or office, the signal may then be sent to computers via wifi, changing medium once again.
• Local Area Network Traffic—Local network traffic causes congestion which can bottleneck the network. This directly impacts both transmitting and receiving signals from connected devices. For example, the use of streaming services by multiple devices on the same network will cause congestion, but for other users trying to send and receive transmissions they may experience increases in RTD.
• Server Response Time—On the opposite side of a transmission from the requesting user is the server response. How quickly a server can respond to a request will impact the RTD. In fact, this is a classic attack by cybercriminals, known as a denial-of-service attack (DoS) when a server is flooded by requests in order to overload it and either stall access or deny it completely. Based on this example, the main principle for servers is the number of requests it must attend to, the greater the amount, the more likely it will impact RTD .
• Internet Routing And Congestion—Perhaps the aspect affecting round trip delay that is least controlled by IT departments is the routing of a signal across the internet. A signal travels from sender to receiver and back through a route that will pass through any number of nodes along the internet. Each node has its own network traffic that the signal must pass through, which factors into the RTD calculation. Generally the greater number of nodes that the signal travels through the more congestion it must contend with and ultimately the longer the signal will take.
• Physical Distance Of Transmission—Closely related to the transmission medium, the physical distance a signal must travel to reach its destination is limited by the laws of physics and the speed of light. In most long distance transmissions, fiber optics use light to send massive amounts of data efficiently, but even that is not instantaneous.

Related Terms

Network Latency

Network latency is the duration of time it takes a data packet to travel from its source to its destination across a network. In terms of user experience, network latency translates to how fast a user’s action produces a response from a network, say how quick a web page accesses and loads over the internet, or the responsiveness of an online game to the gamer’s commands.

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Understanding & Reducing Network Round-Trip Time (RTT in Networking)

Table of contents.

In the dynamic realm of modern business operations, the heartbeat of connectivity relies on the seamless flow of information across networks. Network administrators and IT professionals, entrusted with the pivotal responsibility of maintaining these vital lifelines, understand the significance of every nanosecond.

In a world where time equates to money and efficiency is non-negotiable, the RTT in networking emerges as a pivotal metric. It represents the time taken for a packet of data to travel from its source to its destination and back again, reflecting the responsiveness and effectiveness of your network infrastructure. As businesses increasingly rely on cloud-based applications, remote collaboration tools, and real-time data analytics, the optimization of RTT has become more critical than ever.

In this comprehensive exploration, we will decode the intricacies of Network Round-Trip Time, demystifying its importance and empowering network administrators and IT professionals with actionable insights to reduce RTT and enhance network performance.

What is Network Round-Trip Time (RTT in Networking)?

First, let’s make sure we’re all on the same page.

Network Round-Trip Time (RTT) in networking, also commonly referred to as Round-Trip Latency or simply Latency, is a crucial metric that measures the time it takes for a packet of data to travel from its source to its destination and back again to the source . RTT is typically expressed in milliseconds (ms) and is a fundamental aspect of network performance.

Here's a breakdown of what RTT encompasses:

• Transmission Time : This is the time it takes for a packet of data to travel from the sender to the receiver. It includes the propagation time (the time it takes for the signal to physically travel through the network medium) and the processing time (the time it takes for routers, switches, and other network devices to handle the packet).
• Propagation Delay : This is the time it takes for an electrical or optical signal to travel over the physical medium, such as a copper or fibre-optic cable. Propagation delay depends on the distance the signal needs to cover and the speed of light or electricity in the medium.
• Queuing and Processing Delay : As data packets pass through routers and switches in a network, they may spend some time in queues waiting for their turn to be processed. This queuing and processing delay can vary based on network congestion and the efficiency of network devices.

In summary, Network Round-Trip Time (RTT) is a key metric in networking that measures the time it takes for data to travel from its source to its destination and back, encompassing transmission time, propagation delay, and queuing/processing delay. It plays a significant role in determining the responsiveness and efficiency of networked applications and services.

The Role of RTT (Network Round-Trip Time) in Network Responsiveness

Network responsiveness, often measured by RTT, is the cornerstone of user satisfaction and efficient operations.

RTT is a critical factor in network performance because it directly impacts the responsiveness of network applications and services. Low RTT values indicate that data can travel quickly between endpoints, resulting in faster response times for applications and a more seamless user experience. On the other hand, high RTT values can lead to delays and sluggish performance.

Reducing RTT is essential in scenarios where real-time communication, online gaming, video conferencing, or the timely delivery of data is crucial. Network administrators and IT professionals often work to optimize RTT by employing various strategies such as using content delivery networks (CDNs), minimizing network congestion, and optimizing routing paths.

• User Expectations : Today's users have high expectations for network responsiveness. Whether it's loading a web page, streaming a video, or making a VoIP call, users demand minimal delays. A low RTT ensures that users experience quick response times, leading to seamless and satisfactory interaction with applications and services.
• Real-Time Applications : Many critical business applications, such as video conferencing, online collaboration tools, and financial trading platforms, require real-time data exchange. RTT directly impacts the effectiveness of these applications. A shorter RTT means that data reaches its destination faster, enabling real-time interactions without noticeable delays.

I. Network Round-Trip Time (RTT) and User Experience

User experience is a key driver of customer satisfaction and loyalty. RTT plays a pivotal role in shaping this experience.

• Website Performance : For businesses with an online presence, website performance is paramount. A website with low RTT loads quickly, ensuring that visitors can access information, make purchases, or engage with content without frustrating delays. Studies have shown that longer page load times due to high RTT can result in higher bounce rates and decreased conversions.
• Video and Media Streaming : In an era of video marketing and content consumption, RTT directly influences the quality of video streaming. Lower RTT values mean faster buffer-free streaming, enhancing the viewer's experience and reducing the likelihood of video interruptions.

II. Network Round-Trip Time’s (RTT) Impact on Business Operations

Beyond user experience, RTT has a profound impact on various aspects of business operations:

• Productivity : In a remote or hybrid work environment, where employees rely on cloud-based applications and data access, RTT can significantly impact productivity. Sluggish network performance due to high RTT values can lead to frustration, downtime, and decreased efficiency.
• Data Transfer : Businesses often need to transfer large volumes of data between locations or to the cloud. High RTT can lead to slow data transfer speeds, potentially affecting data backup, disaster recovery, and the ability to access critical information in a timely manner.
• Customer Service : For businesses that provide customer support or run call centers, low RTT is essential for clear and uninterrupted VoIP calls. High RTT can lead to call dropouts, poor call quality, and dissatisfied customers.
• E-commerce : In the world of e-commerce, where every millisecond counts, RTT can impact sales and customer retention. Slow-loading product pages and checkout processes due to high RTT values can result in abandoned shopping carts and lost revenue.

Understanding the significance of RTT in modern networking is not just a technical matter; it's a fundamental aspect of delivering a positive user experience, maintaining productivity, and ensuring the seamless operation of critical business processes. Network administrators and IT professionals must prioritize RTT optimization to meet the demands of today's digital business landscape.

Ready to Optimize Your Network's Round-Trip Time? Try Obkio Today!

Are you eager to take control of your network's performance and reduce Round-Trip Time (RTT) to boost productivity and enhance user experiences? Look no further than Obkio's Network Performance Monitoring tool, the ultimate solution for network administrators and IT professionals.

Why Choose Obkio:

• Real-Time Monitoring : Obkio provides real-time visibility into your network, allowing you to identify latency bottlenecks and pinpoint performance issues as they happen.
• User-Friendly Interface : With an intuitive and user-friendly interface, Obkio makes it easy to monitor your network's RTT and other critical metrics without the need for complex configurations.
• Actionable Insights : Obkio offers actionable insights and recommendations to help you optimize your network's performance, reduce RTT, and ensure seamless business operations.
• Customized Alerts : Set up custom alerts to be notified of performance deviations, ensuring that you can proactively address issues before they impact your users.

Unlock the Full Potential of Your Network with Obkio. Get Started Today!

Don't let network latency hold your business back. Take the first step towards optimizing your network's Round-Trip Time and providing an exceptional user experience. Try Obkio's Network Performance Monitoring tool now and experience the difference.

Measuring and Calculating Network Round-Trip Time: How to Calculate RTT

While understanding the significance of RTT is vital, the ability to quantify and interpret it accurately is equally crucial for network administrators and IT professionals.

In this section, we’ll equip you with the knowledge and tools necessary to measure, calculate, and make sense of RTT metrics effectively. RTT measurement is not merely a technical exercise; it's a strategic endeavour that empowers you to fine-tune your network for peak performance, deliver an exceptional user experience, and ensure the seamless operation of critical business processes.

So, join us as we explore the RTT formula, discover the range of tools at your disposal for RTT measurement, and learn the art of interpreting RTT metrics.

I. Understanding the Network RTT Formula

The RTT formula is a fundamental concept for anyone aiming to measure and manage network latency effectively. It provides a straightforward way to calculate the Round-Trip Time between two endpoints in a network.

The formula for RTT is as follows:

RTT = (t2 - t1) + (t4 - t3)

• t1 : The time at which the sender sends the packet.
• t2 : The time at which the sender receives an acknowledgment (ACK) from the receiver.
• t3 : The time at which the receiver receives the packet.
• t4 : The time at which the receiver sends the ACK back to the sender.

Understanding this formula allows you to measure RTT manually by recording these timestamps. In practice, however, RTT is often measured automatically using specialized tools and software.

I. Tools for Measuring Network RTT

Accurate RTT measurement is crucial for network administrators and IT professionals. Fortunately, a range of tools and methods are available to simplify this process:

• Network Monitoring Software : Comprehensive network monitoring solutions, such as Obkio's Network Performance Monitoring tool , offer real-time RTT measurement and historical data tracking. These tools provide insights into RTT trends, allowing you to identify performance fluctuations and optimize network resources.
• Ping : The ping command is a simple and widely used tool for measuring RTT. It sends ICMP echo requests to a destination and records the time it takes for responses to return. While ping provides basic RTT information, it may not be suitable for more detailed analysis.
• Traceroute : Traceroute is another command-line tool that helps you trace the path a packet takes to reach its destination. It provides information about each hop along the route, including RTT values. Traceroute is useful for diagnosing latency issues and identifying bottlenecks in the network.
• Packet Analyzers : Packet analyzers like Wireshark capture network packets and provide detailed analysis, including RTT calculations. They are invaluable for diagnosing complex network issues but require a deeper understanding of packet-level data.
• Cloud-Based Monitoring Services : Cloud-based services can measure RTT from multiple locations globally, offering a broader perspective on network performance. These services often include user-friendly dashboards and alerting features.

III. Interpreting Network RTT Metrics

Interpreting RTT metrics is essential for making informed decisions about network optimization. Here's how to understand the data:

• Baseline RTT : Establish a baseline RTT for your network under normal operating conditions. This baseline serves as a reference point for identifying deviations and potential issues.
• Variability : Monitor the variability of RTT values over time. Consistently high or fluctuating RTT can indicate network congestion, equipment problems, or other performance bottlenecks.
• Comparing RTT Metrics : Compare RTT metrics between different endpoints, routes, or network segments. This can help pinpoint specific areas of concern and prioritize optimization efforts.
• Thresholds and Alerts : Set RTT thresholds and network monitoring alerts to be notified when latency exceeds acceptable levels. Proactive alerting allows you to address performance issues before they impact users.
• Root Cause Analysis : When RTT metrics indicate performance problems, use additional tools and diagnostics to perform a root cause analysis. Isolate the source of latency and implement corrective measures.

Interpreting RTT metrics effectively empowers network administrators and IT professionals to make data-driven decisions, optimize network performance, and deliver a seamless user experience.

In conclusion, understanding the RTT formula, utilizing measurement tools, and interpreting RTT metrics are essential steps in managing and improving network latency. These skills enable network professionals to diagnose issues, identify opportunities for optimization, and ensure efficient network performance.

IV. How to Calculate RTT in Networking: An Example

Let's walk through a simple example of calculating Network Round-Trip Time (RTT) for a packet of data travelling between two devices.

Suppose you have a sender ( Device A ) and a receiver ( Device B ) connected to the same network. You want to measure the RTT for a packet of data sent from Device A to Device B and back.

Here are the key timestamps you'll need to measure or record:

• t1 : The time at which Device A sends the packet.
• t2 : The time at which Device A receives an acknowledgment (ACK) from Device B.
• t3 : The time at which Device B receives the packet.
• T4 : The time at which Device B sends the ACK back to Device A.

Now, let's assume the following timestamps:

• t1 : 12:00:00.000 (Device A sends the packet)
• t2 : 12:00:00.150 (Device A receives the ACK from Device B)
• t3 : 12:00:00.200 (Device B receives the packet)
• t4 : 12:00:00.350 (Device B sends the ACK back to Device A)

Now, you can use the RTT formula to calculate the Round-Trip Time:

Plug in the values:

RTT = (12:00:00.150 - 12:00:00.000) + (12:00:00.350 - 12:00:00.200)

RTT = 0.150 seconds + 0.150 seconds

RTT = 0.300 seconds

So, in this example, the calculated Network Round-Trip Time (RTT) for the packet travelling between Device A and Device B is 0.300 seconds, or 300 milliseconds (ms).

This RTT value represents the time it took for the data packet to travel from Device A to Device B and back, including the time it spent in transit and the time it took for the acknowledgment to return.

In this article, we explore the importance of testing network latency for businesses and provide tools and techniques for accurately measuring latency.

How to Measure Network Round-Trip Time with NPM Tools

When it comes to measuring and optimizing Network Round-Trip Time (RTT), Network Performance Monitoring (NPM) tools are your go-to.

NPM tools provide real-time visibility into network performance and continuously and comprehensively monitor various aspects of a network, allowing network administrators to track RTT metrics at multiple points in the network infrastructure.

By offering a granular view of RTT, NPM tools help identify performance bottlenecks, allowing for swift diagnosis and targeted optimization. Additionally, NPM tools often include alerting features that notify administrators when RTT exceeds predefined thresholds, enabling proactive problem resolution before end-users experience the impact.

Moreover, NPM tools are equipped with historical data analysis capabilities, allowing network professionals to identify trends and patterns in RTT values. By identifying long-term RTT patterns, administrators can make informed decisions about capacity planning, infrastructure upgrades, or routing optimization to ensure consistent low-latency network performance.

In a world where network responsiveness is crucial for user satisfaction and business productivity, NPM tools are invaluable for network administrators and IT professionals aiming to maintain optimal RTT and deliver a seamless user experience. Let’s learn how to deploy them!

Step 1. Deploy A Network Performance Monitoring Tool with RTT Monitoring Features

High RTT can lead to delays and sluggish network performance - but how can you know the extent of the problem?

The most accurate way to measure RTT and other key network metrics is by using a Synthetic Network Performance Monitoring Software, like Obkio.

Unlike standalone RTT monitoring tools, Obkio provides a holistic approach to network performance analysis, making it the best choice for measuring RTT and network performance as a whole. With Obkio, gain access to real-time monitoring and reporting features that allow them to measure RTT across their entire network infrastructure, including routers, switches, and end-user devices.

This end-to-end network monitoring tool not only identifies RTT issues but also provides valuable insights into latency, packet loss, bandwidth utilization and more.

Obkio continuously measures network metrics like network RTT by:

• Using Network Monitoring Agents in key network locations
• Simulate network traffic with synthetic traffic and synthetic testing
• Sending packets every 500ms to measure the round trip time it takes for data to travel
• Catch RTT and other network issues affecting key applications and services

Step 2. Measure Round-Trip Time in All Network Locations

Persistent and erratic spikes in Network Round-Trip Time (RTT) measurements are indicative of substantial performance challenges within your network, demanding immediate attention. To pinpoint and resolve these irregularities, implementing RTT monitoring is an indispensable step.

Obkio’s Network Monitoring Solution will measure RRT and other network metrics by sending and monitoring data packets through your network every 500ms using Network Monitoring Agents . The Monitoring Agents are deployed at key network locations like head offices, data centers, and clouds and continuously measure the amount of time it takes for data to travel across your network.

This is extremely important when monitoring RTT and addressing spikes to maintain network efficiency and a smooth user experience, especially in scenarios where real-time data exchange, applications, and services are critical.

For example , you can measure network RTT between your head office and the Microsoft Azure cloud, or even between Azure and your data center.

To deploy monitoring in all your network locations, we recommend deploying:

• Local Agents : Installed in the targeted office location experiencing performance issues or latency spikes. There are several Agent types available (all with the same features), and they can be installed on MacOS, Windows, Linux and more.
• Public Monitoring Agent : These are deployed over the Internet and managed by Obkio. They compare performance up to the Internet and quickly identify if the performance issue is global or specific to the destination. For example, measure RTT between your branch office and Google Cloud .

Step 3. Measure Round-Trip Time for Network Devices

Network Device Monitoring is also crucial for accurately measuring and managing Network Round-Trip Time (RTT). Network devices, such as routers, switches, and firewalls, play a significant role in determining the latency and RTT experienced by data packets as they traverse the network.

Obkio’s Network Device Monitoring feature is a fast and easy solution to get detailed information about the health of your core network devices. Used with the end-to-end Network Performance Monitoring feature, Network Device Monitoring with SNMP Polling helps IT teams quickly and proactively pinpoint issues with devices like firewalls, routers, switches and Wi-Fi access points.

Network devices are key points of control and routing within a network. Monitoring these devices allows you to gain insights into their performance, such as how efficiently they process and forward data packets. Device monitoring helps identify issues like high CPU utilization, memory constraints, or network interface errors, which can all contribute to increased RTT.

Here are the key network devices you should consider monitoring when measuring network round-trip time:

• Routers : Routers are pivotal devices in network traffic management. They determine the path data packets take between networks and subnetworks. Monitoring routers helps identify congestion points, routing issues, and overall device performance.
• Switches : Network switches are responsible for forwarding data packets within a local network (LAN). Monitoring switches helps ensure that LAN traffic is efficiently handled and doesn't introduce unnecessary RTT.
• Firewalls : Firewalls are essential for network security but can also introduce latency. Monitoring firewalls helps verify that they're processing data packets efficiently and not creating undue RTT delays.
• Load Balancers : Load balancers distribute network traffic across multiple servers or resources to ensure load distribution and fault tolerance. Monitoring load balancers helps maintain even traffic distribution and low RTT.
• Gateways : Gateways connect different networks, such as LANs to the internet. Monitoring gateways is essential for ensuring data packets are efficiently routed between internal networks and external destinations.
• WAN Optimization Devices : These devices are commonly used in wide-area networks (WANs) to reduce latency and optimize data transfer. Monitoring WAN optimization devices ensures they're operating as intended to minimize RTT.
• Access Points (APs) : In wireless networks, APs play a critical role in data transmission. Monitoring APs helps maintain consistent wireless network performance, minimizing RTT for mobile or remote users.
• DNS Servers : DNS (Domain Name System) servers translate domain names into IP addresses. Monitoring DNS servers ensures that DNS resolution doesn't introduce delays when clients access network resources.
• Network Endpoints : Monitoring the performance of endpoints (e.g., servers, workstations, and user devices) is vital for understanding how network devices affect RTT from the user's perspective.
• Virtualization and SDN Controllers : In virtualized or software-defined networks, controllers manage network resources and routing. Monitoring these controllers helps ensure efficient data flow and low RTT.

To comprehensively measure and optimize RTT, it's essential to monitor a variety of network devices . The choice of devices to monitor may depend on the specific characteristics of your network and the critical points for your organization.

Step 4. Collect Network Round-Trip Time Measurements

Once you’ve set up your Monitoring Agents for network latency monitoring , they continuously measure metrics like RTT measure and collect data, which you can easily view and analyze on Obkio’s Network Response Time Graph.

Measure RTT throughout your network with updates every minute. This will help you understand and measure good round-trip time measurements for different applications vs. poor latency. If your RTT levels go from good to poor, you can also further drill down to identify exactly why RTT issues are happening, where they’re happening, and how many network locations they’re affecting.

To more accurately measure RTT in your network, and receive alerts when latency measurements are poor, Obkio sends alerts based on historical data and not just static thresholds.

As soon as there’s a deviation in the historical data, and your network is experiencing poor RTT measurements, Obkio sends you an alert.

It’s as simple as that

Step 5. Monitor More Network Metrics Alongside Network Round-Trip Time

Once deployed, Obkio’s Monitoring Agents will begin exchanging synthetic traffic to continuously measure network performance and core network metrics .

When monitoring network performance and assessing the health of your network, it's important to measure a range of network metrics alongside Network Round-Trip Time (RTT) to gain a comprehensive understanding of the network's behaviour and potential issues. Here are several key network metrics to consider:

• Packet Loss : Packet loss indicates the percentage of data packets that fail to reach their destination. High packet loss can significantly impact the quality of network services and applications.
• Jitter : Jitter is the variation in latency or RTT. Consistent RTT values are desirable, but high jitter can lead to unpredictable network performance, which is problematic for real-time applications like VoIP and video conferencing.
• Bandwidth Utilization : Monitoring bandwidth usage helps you identify periods of congestion and overutilization, which can lead to increased RTT. By monitoring bandwidth, you can proactively manage network capacity.
• Throughput : Throughput measures the rate at which data is transmitted over the network. It's essential for assessing the actual data transfer capacity of your network, especially for large file transfers or media streaming.
• Error Rate : The network error rate indicates the number of data packets with errors or corruption. High error rates can lead to retransmissions, increasing latency and packet loss.
• QoS Metrics : Quality of Service (QoS) metrics include parameters like latency, jitter, and packet loss, specific to certain traffic types. Monitoring QoS compliance is essential for prioritizing critical applications and ensuring they meet performance requirements.
• Device Performance : Monitoring the performance of network devices such as routers, switches, and firewalls is crucial. High CPU usage , memory issues, or hardware problems can impact network performance and increase RTT.
• Availability and Uptime : Monitoring network availability and network uptime is essential for identifying periods of network unavailability or downtime, which can impact services and applications.

By measuring these network metrics alongside RTT, you can gain a holistic view of your network's performance, detect issues promptly, and proactively optimize network resources to provide a seamless user experience and support critical business operations.

Understanding Good vs. Bad Network Round-Trip Time Measurements

In the intricate world of networking, the metric known as Network Round-Trip Time (RTT) serves as a crucial barometer of performance. However, RTT is not a one-size-fits-all metric, and its evaluation must be tailored to the specific needs and demands of a network or application.

In this section, we delve into the nuanced realm of RTT measurements, deciphering what constitutes good and bad readings, and how these metrics reverberate through the fabric of network performance.

Good and bad RTT measurements are relative and depend on the specific context and requirements of a network or application. What is considered good or bad RTT can vary based on factors such as the type of network, the application's sensitivity to latency, and the expectations of users. However, here are some general guidelines to consider:

I. Good Network RTT Measurements

• Low and Consistent : Good RTT measurements typically exhibit low and consistent values. Low RTT indicates that data is transmitted quickly, providing a responsive user experience. Consistency ensures that users can rely on predictable network performance.
• Match Application Requirements : Good RTT measurements should meet or exceed the requirements of the applications and services being used. For example, real-time applications like video conferencing or online gaming often require RTT values below 100 milliseconds to provide a seamless experience.
• Minimal Jitter : Good RTT measurements have minimal jitter, meaning that there is little variation in RTT values. Jitter can disrupt real-time applications, so a stable and low-latency network is desired.

II. Bad Network RTT Measurements:

• High and Fluctuating : Bad RTT measurements typically exhibit high values and significant fluctuations. High RTT values can lead to sluggish network performance and application responsiveness, while fluctuations introduce unpredictability.
• Exceed Application Tolerances : For some applications, any RTT values beyond specific thresholds can be considered bad. For example, an online multiplayer game might become unplayable with RTT exceeding 200 milliseconds.
• Frequent Packet Loss : Consistent packet loss and retransmissions can lead to bad RTT measurements. Packet loss is a sign of network congestion or instability, and it can severely impact network performance.
• Long-Term Performance Issues : Consistently bad RTT measurements over an extended period, even if they are not extremely high, may indicate underlying network issues that need to be addressed. It's essential to identify and resolve long-term performance problems to maintain a reliable network.

In summary, good RTT measurements are characterized by low, consistent values that meet the requirements of the network's applications, with minimal jitter. Bad RTT measurements, on the other hand, involve high, fluctuating values, packet loss, and latency that exceeds application tolerances. To assess RTT measurements, it's important to consider the specific network requirements and the impact of latency on user experience in your particular environment.

Identifying, Troubleshooting, and Common Network Round-Trip Time (RTT) Issues

In the world of networking, Network Round-Trip Time (RTT) serves as a vital performance indicator. When RTT issues arise, they can lead to sluggish network responsiveness and user dissatisfaction. This section is your guide to identifying and troubleshooting common RTT problems that can affect network performance.

We'll dive into the practical aspects of recognizing RTT issues, whether through real-time monitoring or user feedback. We'll also explore the common culprits behind elevated RTT, such as congestion and configuration problems.

I. Identifying Network RTT Issues

• Real-time Monitoring : Regularly monitor RTT using network performance monitoring tools, like Obkio NPM . These tools provide real-time data on RTT, enabling you to detect anomalies or spikes that might indicate issues.
• Baseline Measurement : Establish a baseline for expected RTT values in your network. Deviations from this baseline can be an early indicator of RTT problems.
• User Feedback : Listen to user complaints or feedback. Slow application response times or connectivity issues reported by users can be indicative of RTT issues.
• Historical Analysis : Analyze historical RTT data to identify patterns or trends. Consistent RTT issues at specific times or on particular network segments can point to the source of the problem.
• Network Topology Review : Examine your network topology to identify potential bottlenecks or congestion points that may contribute to high RTT.

II. Uncovering The Most Common Network RTT Issues

• Network Congestion : Heavy network traffic can lead to network congestion , queuing delays, and packet loss, resulting in increased RTT. Implement Quality of Service (QoS) to prioritize essential traffic and reduce congestion.
• Long Geographic Distance : Data travelling over long distances, especially in wide-area networks (WANs), can experience high propagation delay, contributing to elevated RTT. Consider implementing content delivery networks (CDNs) to reduce the impact of distance.
• Hardware and Configuration Problems : Outdated or misconfigured network devices, such as routers and switches, can lead to performance issues and high RTT. Regularly review and update hardware and configurations to address these problems.
• Packet Loss : Packet loss , where data packets are dropped or need to be retransmitted, can increase RTT. Troubleshoot packet loss issues by identifying and rectifying network faults or congestion points.
• Jitter : Inconsistent RTT values and jitter can affect real-time applications. Jitter is often a result of network congestion or configuration problems, so minimizing these issues helps reduce jitter and improve RTT.

III. Troubleshooting Network RTT Issues:

So what happens when your NPM tool starts alerting you about sudden spikes in round-trip time? Well, it’s time to troubleshoot! First, you need to understand why the network issue is happening, where and when.

• Isolate the Problem : Start by identifying the affected network segment or path with high RTT. Network monitoring tools can help pinpoint the problematic area.
• Traffic Analysis : Analyze the network traffic on the identified segment to determine if congestion or unusual patterns are causing high RTT.
• Device Inspection : Examine the performance of network devices along the path, such as routers and switches. High CPU usage or configuration errors may be contributing to RTT issues.
• Quality of Service (QoS) Adjustment : If network congestion is the root cause, consider implementing or adjusting QoS policies to prioritize critical traffic and reduce congestion.
• Optimization Techniques : Implement optimization techniques such as route optimization, network load balancing , and the use of CDNs to improve network efficiency and reduce RTT.
• Testing and Validation : After making adjustments, conduct tests to validate that RTT has improved. Monitor the network to ensure that RTT remains within acceptable ranges.
• Regular Maintenance : Ongoing network maintenance, including updates, hardware upgrades, and configuration reviews, is essential for preventing future RTT issues.

By systematically identifying, troubleshooting, and addressing RTT issues, network administrators can maintain low-latency networks, ensure a seamless user experience, and minimize the impact of common RTT problems.

Learn how to troubleshoot network issues by identifying where, what, why network problems occur with Network Troubleshooting tools.

Factors Affecting Network Round-Trip Time (RTT)

As we navigate the realm of Network Round-Trip Time (RTT) and its role in network optimization, we encounter an array of influential factors that shape the journey of data from source to destination and back. In this chapter, we embark on a comprehensive exploration of these key factors, each wielding the power to either elevate or hinder network performance.

Understanding the factors affecting RTT is paramount for network administrators and IT professionals, as it equips them with the knowledge needed to fine-tune their networks for maximum efficiency and responsiveness.

1. Network Congestion on RTT in Networking

Network congestion occurs when there is a higher volume of traffic on a network than it can efficiently handle. This congestion can significantly impact RTT:

• Increased Latency : Congestion leads to packet queuing, where data packets must wait in line to be processed by network devices. The increased latency due to this queuing results in higher RTT values, causing delays in data transmission.
• Packet Loss : In congested networks, packets may be dropped to relieve congestion. This packet loss not only contributes to higher RTT as packets are retransmitted but also affects the reliability and performance of network applications.
• Quality of Service (QoS) : Implementing Quality of Service policies can help mitigate congestion by prioritizing certain types of traffic. This can help ensure that critical applications experience lower RTT values even during network congestion.

2. Geographic Distance on RTT in Networking

Geographic distance plays a fundamental role in determining RTT, especially in wide-area networks and global connectivity:

• Propagation Delay : As data travels over long distances, it experiences propagation delay. This delay is the time it takes for signals to traverse the physical medium (e.g., fibre-optic cables or satellite links) between network endpoints. The greater the distance, the higher the propagation delay, contributing to increased RTT.
• WAN vs. LAN : Wide Area Networks ( WANs ) typically involve greater geographic distances than Local Area Networks ( LANs ). WANs often exhibit higher RTT values due to the inherent challenges of data transmission across extensive physical distances.
• Use of Content Delivery Networks (CDNs) : CDNs can help mitigate the impact of geographic distance by caching and delivering content from servers closer to end-users. This minimizes the effects of long-distance transmission on RTT.

3. Network Hardware and Configurations on RTT in Networking

The hardware and configuration of network devices and infrastructure can significantly affect RTT:

• Router and Switch Performance : The processing capacity of routers and switches in the network can impact the speed at which packets are forwarded. Outdated or underpowered devices can introduce additional latency and increase RTT.
• Network Path Efficiency : The chosen network paths and routing algorithms also play a role. Inefficient routing can lead to longer paths and, subsequently, higher RTT.
• Configuration Errors : Misconfigurations in network devices, such as incorrect routing tables or Quality of Service settings, can lead to suboptimal performance and increased RTT. Regular network audits and optimization are essential to address configuration issues.

4. Packet Loss and Jitter on RTT in Networking

Packet loss and jitter are network phenomena that can cause variations in RTT:

• Packet Loss : Packet loss occurs when data packets fail to reach their intended destination. Repeated packet loss results in retransmissions, which contribute to increased RTT. Reducing and measuring packet loss through network optimization is essential for minimizing RTT.
• Jitter : Jitter refers to the variation in packet arrival times. Excessive jitter can cause fluctuations in RTT, affecting the predictability of network performance. QoS mechanisms and traffic shaping can help mitigate jitter-related RTT issues.

Understanding these factors and their impact on RTT is crucial for network administrators and IT professionals. By addressing these challenges through proactive network management, optimization, and the use of appropriate technologies, it's possible to achieve lower RTT and maintain efficient and responsive network performance.

Network Round-Trip Time (RTT) vs. Latency: Comparing Network Siblings

In the world of networking and data transmission, terms like "Network Round-Trip Time (RTT)" and "latency" often take center stage, reflecting the critical aspect of speed and responsiveness in today's digital landscape. While these terms are sometimes used interchangeably, they represent distinct facets of network performance.

In this section, we’ll unravel the differences between Network Round-Trip Time (RTT) and latency. Understanding these concepts is fundamental for network administrators and IT professionals as it enables them to grasp the nuances of network performance and address specific challenges effectively.

I. Defining Latency

Latency is a general term that refers to any delay or lag in data transmission within a network . It encompasses all delays encountered during data communication, including the time it takes for data to travel between two points (which is what RTT specifically measures), as well as other types of delays such as processing delays, queuing delays, and transmission delays.

Latency can be categorized into several types:

• Propagation Delay : The time it takes for a signal or data packet to physically travel over the network medium (e.g., copper cables, fibre-optic cables, or wireless links). It is directly related to the distance between two network points and the speed of the medium.
• Transmission Delay : The time it takes to push the entire data packet into the network medium. It is influenced by the packet's size and the speed of the network link.
• Processing Delay : The time it takes for network devices like routers and switches to process and forward data packets. This can be affected by the performance of these devices and their configurations.
• Queuing Delay : The time data packets spend in queues at various points in the network, waiting for their turn to be processed. High congestion or network traffic can increase queuing delays.
• Jitter : Jitter refers to variations in latency. Inconsistent latency can affect the predictability of network performance, which is particularly critical for real-time applications.

II. Defining Network Round-Trip Time (RTT)

As we've already discussed in this article, RTT is a specific metric used to measure the time it takes for a data packet to travel from its source to its destination and back to the source . It is a subset of latency that focuses on the round-trip journey of a packet. RTT is measured in milliseconds (ms) and is often used to evaluate network responsiveness.

The RTT calculation typically involves the following timestamps:

• The time the sender sends the packet.
• The time the sender receives an acknowledgment (ACK) from the receiver.
• The time the receiver receives the packet.
• The time the receiver sends the ACK back to the sender.

By subtracting the appropriate timestamps, you can calculate the RTT for a specific packet.

In summary, latency is a broader term that encompasses various types of delays in data transmission, including RTT. RTT specifically measures the round-trip time for a packet, which is crucial for understanding the responsiveness of a network, particularly in applications that require timely data exchange, such as video conferencing or online gaming.

We asked a supercomputer “What is latency”, its impact on network performance, and strategies for minimizing it and created this comprehensive guide.

The Quest for Lower Network Round-Trip Time: How to Reduce Network RTT

In the quest for network optimization and superior user experiences, one metric stands as a sentinel of responsiveness - Network Round-Trip Time (RTT). A lower RTT signifies not only the swift transmission of data but also the realization of network efficiency, seamless applications, and satisfied users.

Here, we will explore the art of reducing RTT through a variety of carefully crafted strategies. From optimizing network topology to the art of content caching and compression, from harnessing the power of load balancing to the efficiency of Content Delivery Networks (CDNs), we will venture into the multifaceted realm of RTT reduction.

I. Strategies for Reducing Network RTT

Reducing RTT is a fundamental objective in optimizing network performance . So, there are several strategies to help you achieve this:

• Optimizing Network Topology : A well-designed network topology that minimizes the number of network hops and ensures efficient routing can significantly reduce RTT. Strategies like hierarchical network design and route optimization contribute to lower latency.
• Quality of Service (QoS) Implementation : Prioritizing real-time traffic and critical applications through QoS policies can reduce contention for network resources and lower RTT for those essential services.
• Edge Computing : Deploying computing resources closer to end-users or IoT devices at the network edge can reduce RTT by decreasing the physical distance that data needs to travel.
• TCP/IP Optimization : Fine-tuning TCP/IP parameters and employing technologies like TCP window scaling and selective acknowledgments can improve data transfer efficiency and lower RTT.

II. Load Balancing and Redundancy for Reducing Network RTT

Load balancing and redundancy are vital components in RTT reduction:

• Load Balancing : Distributing network traffic across multiple servers or paths ensures that no single server or network link becomes overwhelmed. This strategy not only increases network capacity but also reduces the likelihood of network congestion and high RTT.
• Redundancy : Implementing redundancy through network failover mechanisms or backup links can mitigate the impact of network failures. Redundancy ensures that if one path experiences issues, traffic can be rerouted quickly, minimizing RTT.

III. Content Delivery Networks (CDNs) for Reducing Network RTT

CDNs are instrumental in RTT reduction, particularly for web content delivery:

• Caching : CDNs cache content on servers located in geographically distributed edge locations. This means users can access content from a nearby server, reducing the need to retrieve data from the origin server, and consequently lowering RTT.
• Content Prioritization : CDNs allow prioritizing and delivering the most critical content quickly, which is especially beneficial for reducing RTT for web pages, images, and videos.

IV. Caching and Compression for Reducing Network RTT

Caching and compression techniques are powerful tools for minimizing RTT:

• Data Caching : Caching frequently accessed data locally, either at the client side or at intermediate network nodes, allows for quicker retrieval of data, reducing RTT.
• Data Compression : Compressing data before transmission and decompressing it at the receiver's end decreases the amount of data to be transferred, ultimately lowering RTT.

By implementing these strategies and technologies, network administrators and IT professionals can actively work to reduce RTT, enhance network performance, and deliver a more responsive user experience. Each strategy offers a unique approach to address latency and can be adapted to the specific needs and goals of the network environment.

Tools and Technologies for Optimizing Network Round-Trip Time: Network RTT Optimization

In the realm of network performance, the pursuit of lower Network Round-Trip Time (RTT) is both an art and a science. It requires the judicious selection and deployment of tools and technologies that act as enablers, elevating networks to realms of enhanced responsiveness and efficiency.

Here, we uncover the spectrum of tools at your disposal, explore their capabilities, and provide insights into the selection process to ensure you choose the right tools that align with your unique business needs. Earlier in this article, we already talked about measuring RTT and identifying RTT issues with Network Performance Monitoring tools - which are also a key tool for optimizing round-trip time.

With the right tools in your arsenal, you can orchestrate a network that not only understands the melody of RTT but dances to its tune, delivering a harmonious and responsive user experience.

I. Network Monitoring and Analytics Solutions for Optimizing Network RTT

Monitoring and analytics tools are instrumental in the quest for RTT optimization:

• Network Performance Monitoring (NPM) : NPM solutions continuously monitor network performance, providing real-time visibility into RTT metrics. They enable network administrators to detect and diagnose issues promptly, making them a vital tool for maintaining low RTT.
• Packet Capture and Analysis Tools : Packet capture tools allow the in-depth analysis of network traffic. Administrators can use these tools to capture and examine packets, enabling them to identify bottlenecks and other issues contributing to RTT delays.
• Network Traffic Analysis : Advanced network traffic analysis solutions provide insights into application behaviour, network usage , and patterns. These tools help optimize network paths and configurations to lower RTT.

II. SD-WAN and Network Optimization Platforms for Optimizing Network RTT

SD-WAN (Software-Defined Wide Area Network) and network optimization platforms offer dynamic solutions for RTT optimization:

• SD-WAN : SD-WAN technology leverages multiple network connections and dynamically routes traffic over the most efficient path. It includes features such as traffic prioritization and application-aware routing, which are beneficial for optimizing RTT for critical applications. The same goes for Dual-WAN networks .
• WAN Optimization Controllers : These devices optimize data traffic between WAN endpoints by employing techniques like data deduplication, compression, and caching. WAN optimization reduces the amount of data transferred, reducing RTT.
• Content Delivery Platforms : Content delivery platforms, combined with CDNs, accelerate the delivery of web content by distributing it to edge servers. This minimizes the physical distance data needs to travel, resulting in reduced RTT for web-based services.

III. Choosing the Right Tools for Optimizing RTT in Your Business

Selecting the right tools for RTT optimization requires careful consideration:

• Assessing Business Needs : Start by identifying the specific requirements of your business. Consider factors like the nature of your applications, your network topology, and your performance goals. This assessment guides the choice of tools and technologies.
• Scalability : Ensure that the selected tools and technologies can scale with your business as it grows. Scalable solutions can adapt to increased network demands without compromising RTT.
• Compatibility : The tools and technologies you choose should seamlessly integrate with your existing network infrastructure. Compatibility ensures smooth implementation and operation.
• Budget Considerations : Evaluate the cost of implementation and ongoing maintenance. Balancing your budget with the need for high-performance tools is vital to achieving cost-effective RTT optimization.
• Monitoring and Maintenance : Plan for continuous monitoring and maintenance of the chosen tools and technologies. Regular updates and adjustments are necessary to adapt to evolving network conditions and maintain low RTT.

By exploring the array of tools and technologies available for RTT optimization and making informed choices that align with your specific network requirements, you can ensure that your network operates at its peak performance, delivering low RTT and a seamless user experience.

Harnessing the Power of Round-Trip Time (Network RTT) Optimization for Business Success

In the fast-paced digital landscape, where every millisecond counts, optimizing Network Round-Trip Time (RTT) should be a top priority for network admins. Achieving low and consistent RTT not only enhances the user experience but also impacts business operations in numerous ways.

For businesses, RTT optimization means improved productivity, reduced downtime, and the ability to leverage real-time applications to their full potential. In e-commerce, it can translate to higher sales, as low latency ensures swift page loads and seamless transactions. For video conferencing and collaboration tools, it means clearer communication and increased efficiency. In the realm of online gaming, it can be the difference between a competitive edge and a frustrating experience for gamers.

By harnessing the power of RTT optimization, businesses ensure that their digital offerings meet the high expectations of today's users and remain competitive in an ever-evolving market.

Measuring and Optimizing Network RTT with Obkio’s NPM Tool

To start measuring and optimizing RTT, you need the right tools, and Obkio's Network Performance Monitoring (NPM) tool stands as a valuable ally.

With Obkio, you can measure, monitor, and optimize RTT with precision. Get real-time insights into network performance, offering visibility into RTT metrics at various network points. Obkio equips network admins and IT professionals with the means to detect and resolve RTT issues promptly, ensuring that network operations remain seamless and efficient. With Obkio, you can proactively manage RTT, detect anomalies, and maintain low-latency network performance.

As you harness the power of Obkio's NPM tool, you're well-equipped to elevate your network to new heights of efficiency, ultimately contributing to the success of your business in a digitally connected world!

• 14-day free trial of all premium features
• Deploy in just 10 minutes
• Monitor performance in all key network locations
• Measure real-time network metrics
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You can rest assured that we're not like those pushy Sellsy people - there's no catch here. We firmly believe in the excellence of our product, but if it's not the right fit for you, we understand and want what's best for you.

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What is round-trip time (RTT) and how to reduce it?

Round-trip time (RTT) is the time it takes for the server to receive a data packet, process it, and send the client an acknowledgement that the request has been received. It is measured from the time the signal is sent till the response is received.

When a user clicks a button on a website, the request is sent to the server as a data packet. The server needs time (RTT) to process the data, generate a response, and send it back. Each action, like sending a form upon a click, may require multiple requests.

RTT determines the total network latency and helps monitor the state of data channels. A user cannot communicate with the server in less than one RTT, and the browser requires at least three round trip times to initiate a connection:

• to resolve the DNS name;
• to configure the TCP connection;
• to send an HTTP request and receive the first byte.

In some latency-sensitive services, e.g., online games, the RTT is shown on the screen.

• Factors affecting RTT

Distance and number of intermediate nodes. A node is a single device on the network that sends and receives data. The first node is the user’s computer. A home router or routers at the district, city, or country level are often intermediate nodes. The longer the distance between the client and server, the more intermediate nodes the data must pass through and the higher the RTT.

Server and intermediate node congestion. For example, a request may be sent to a fully loaded server that is concurrently processing other requests. It can’t accept this new request until other ones are processed, which increases the RTT. The RTT includes the total time spent on sending and processing a request at each hop, so if one of the intermediate nodes is overloaded, the RTT adds up.

You never know exactly to what extent the RTT will grow based on how the infrastructure is loaded; it depends on individual data links, intermediate node types, hardware settings, and underlying protocols.

Physical link types and interferences. Physical data channels include copper, fiber optic, and radio channels. The RTT here is affected by the amount of interference. On the Wi-Fi operating frequency, the noise and other signals interfere with the useful signals, which reduces the number of packets per second. So, the RTT is likely to increase over Wi-Fi than over fiber-optics.

• How to calculate RTT using ping

To measure the RTT, you can run the ping command in the command line, e.g., “ping site.com.”

Requests will be sent to the server using ICMP. Their default number is four, but it can be adjusted. The system will record the delayed time between sending each request and receiving a response and display it in milliseconds: minimum, maximum, and average.

The ping command shows the total RTT value. If you want to trace the route and measure the RTT at each individual node, you can use the tracert command (or traceroute for Linux or Mac OS). It is also can be performed via the command line.

• Normal RTT values

Many factors affect RTT, making it difficult to establish a normal—the smaller the number, the better.

In online games, over 50 milliseconds are noticeable: players cannot accurately hit their targets due to network latency. Pings above 200 milliseconds matter even when users browse news feeds or place online orders: many pages open slowly and not always fully. A buyer is more likely to leave a slow website without making a purchase and never come back, which is what 79 percent of users do .

Let’s compare the pings of the two sites—the US jewelry store Fancy and the German news portal Nachrichtenleicht.de . We will ping them from Germany.

The RTT of a German news portal is almost three times lower than that of a US store because we ping from Germany. There are fewer nodes between the user and the server, which are both in the same country, so the RTT is lower.

• How to reduce RTT

Connect to a content delivery network (CDN). The hosting provider’s servers are usually located in the same region where most of the audience lives. But if the audience of the site grows or changes geographically, and content is requested by users who are far away from the server, RTT increases for them, and the site loading speed is slower. To increase the loading speed, use a CDN.

CDN (Content Delivery Network) is a service that caches (mostly static) content and stores it on servers in different regions. Therefore, only dynamic content is downloaded from the main source server, which is far from the user. Heavy static files—the main share of the website—are downloaded from the nearest CDN server, which reduces the RTT by up to 50 percent.

For example, the client requests content from a CDN-connected site. The resource recognizes that there is a caching server in the user’s region and that it has a cached copy of the requested content. To speed up the loading, the site substitutes links to files so that they are retrieved not from the hosting provider’s servers, but from the caching server instead since it is located closer. If the content is not in the cache, CDN downloads it directly from the hosting server, passes it to the user, and stores it in the cache. Now a client on the same network can request the resource from another device and load the content faster without having refer to the origin server.

Also, CDN is capable of load balancing: it routes requests through redundant servers if the load on the closest one is too high.

Optimize content and server apps. If your website has visitors from different countries/regions, you need a CDN to offset the increased RTT caused by long distances. In addition, the RTT is affected by the request processing time, which can be improved by the below content optimizations:

• Audit website pages for unnecessary scripts and functions, reduce them, if possible.
• Combine and simplify external CSS.
• Combine JavaScript files and use async/await keywords to optimize their processing—the HTML code first, the script later.
• Use JS and CSS for individual page types to reduce load times.
• Use the tag instead of @import url (“style.css”) commands .
• Use advanced compression media technologies: WebP for images, HEVC for video.
• Use CSS-sprites: merge images into one and show its parts on the webpage. Use special services like SpriteMe.
• I want to reduce RTT with CDN. What provider to choose?

For fast content delivery anywhere in the world, you need a reliable CDN with a large number of points of presence. Try Gcore CDN —this is a next-generation content delivery network with over 140 PoPs on 5 continents, 30 ms average latency worldwide, and many built-in web security features. It will help to accelerate the dynamic and static content of your websites or applications, significantly reduce RTT, and make users satisfied.

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Geostationary satellite latency and time delay ms

Most communications satellites are located in the Geostationary Orbit (GSO) at an altitude of approximately 35,786 km above the equator.  At this height the satellites go around the earth in an eastery direction at the same angular speed at the earth's rotation, so they appear to be almost fixed in the sky to an observer on the ground. The earth surface also moves in an easterly direction, so that the sun rises in the east.

The time for one satellite orbit and the time for the earth to rotate is 1 sidereal day or 23 h 56 m 4 seconds.   

Radio waves go at the speed of light which is 300,000 km per second.

If you are located on the equator and are communicating with a satellite directly overhead then the total distance, single hop  (up and down) is nearly 72,000 km so the time delay is 240 ms .   mS means millisecond or 1 thousandth of a second so 240 mS is just under a quarter of a second.

A geostationary satellite is visible from a little less than one third of the earth's surface and if you are located at the edge of this area the satellite appears to be just above the horizon.  The distance to the satellite is greater and for earth stations at the extreme edge of the coverage area, the distance to the satellite is approx 41756 km.  If you were to communicate with another similarly located site, the total distance is nearly 84,000 km so the end to end delay is almost 280 mS , which is a little over quarter of a second.

Extra delays occur due to the length of cable extensions at either end, and very much so if a signals is routed by more than one satellite hop.

Significant delay can also be added in routers, switches and signal processing points along the route.

Satellites in lower orbits

In recent years there has been increasing interest in low earth orbit (LEO) and medium earth orbit (MEO) satellite networks. These satellites move across the sky and need tracking (or low gain omni-directional) antennas on the ground. Coverage visibility of the earth is less than for geostationary satellites and to provide continuous coverage multiple satellites are used for each network, configured in constellations with complex interlocking orbits designed to give users visibility of one or two satellites at all times. As many as 1000 satellites may be proposed in a such constellation.

O3b MEO network

O3b is an operating constellation of 12 satellites, spaced along in a single medium height orbit directly above the equator . The height is 8062km and this results in lower latency compared with geostationary.  This is a key selling point. If a typical single hop path involves sloping path lengths of 11000km the single hop distance is 22000km with a latency of  73 mS. O3b claim a round trip latency of better then 150mS. 150 mS round trip refers to a double hop distance of 11250 + 11250 + 11250 + 11250 km.

Proposed OneWeb network

This is a proposed LEO satellite constellation with some 648 satellites at a height of 1200km.  Typical single hop latency, corresponding to 1500km + 1500km would be 10 mS. If the terrestrial end points are not within the coverage of a single satellite (approx 1000km x 1000km) then the distance will be greater, with inter-satellite links via other satellites. I have started a new discussion forum about OneWeb . Please sign up and contribute if you can.

TCP/IP Acceleration:

The use of the TCP/IP protocol over satellite may be improved and a number of companies have developed ways of changing the protocol over the satellite link to achieve IP acceleration.

Two-way time transfer involves signals that travel both ways between the two clocks or oscillators that are being compared, as shown in the figure below. A half-duplex channel is a one-way system that is turned around to retransmit a signal in the opposite direction. In this method, the one-way delay between the transmitter and receiver is estimated as one-half of the measured round trip delay. The delay estimate can be sent to the user and applied as a correction, or the transmitter can advance the signal so that it arrives at the user's site on time. The latter is how the NIST Automated Computer Time Service (ACTS) system works. Internet time transfers using the Network Time Protocol (NTP) also use a half-duplex technique. A full-duplex system uses one-way signals transmitted simultaneously in both directions. In this case data must be exchanged in both directions so that the two data sets can be differenced.

Both two-way methods have advantages and limitations. The half-duplex system has the advantage of only requiring "reflecting" hardware at one station, but it is susceptible to fluctuations in the delay, especially when the period of the fluctuations is comparable to the round trip delay. A full-duplex system does not have this problem since timing information is transmitted in both directions simultaneously. However, it requires complete transmit and receive hardware at both stations.

A full duplex two-way system does not depend on the actual length of the path, provided that the inbound and outbound delays are equal. This requirement may be difficult to realize completely since these systems usually require separate station hardware for the two directions (with delays that may not be the same). The transmission medium can also cause asymmetries if it is dispersive and if the signals in the two directions use different frequencies.

A full duplex two-way technique using a geostationary communications satellite as a relay station is illustrated below. This technique is called Two-Way Satellite Time and Frequency Transfer (TWSTFT). The TWSTFT technique provides stable and accurate time transfer since nearly all of the propagation delay cancels out due to symmetry. Recently the Bureau International des Poids et Mesures (BIPM) has started using two-way via a commercial Ku-band communication satellite as the primary time transfer technique for some European and transatlantic links, since it performs significantly better than GPS common-view . A significant disadvantage of TWSTFT is the added complexity of having to have both transmit and receive hardware at each station. It is also more expensive, since it requires paying for satellite time if a commercial communications satellite is used.

In the TWSTFT technique the basic time interval measurements are made with Time Interval Counters (TICs) at each site. The TICs are started by a pulse from the local clock and stopped by the received pulse from the remote clock. At the same time as the local clock pulse is starting the TIC it is also being transmitted to the other station. The same process goes on at both stations. Typically a one pulse per second (PPS) signal is used. This time interval data is recorded at both sites and then the data files are exchanged and differenced. Generally there is sufficient bandwidth in the communications link that the data can be transferred at the same time that the timing pulses are being transmitted. Thus the two-way technique can be used in essentially real time. The time interval information that is recorded at each station contains the clock differences as well as various delays as shown in the equations below.

TIC(A) = A - B + d TB + d BS + d SBA + d SA + d RA + S B      (1)

TIC(B) = B - A + d TA + d AS + d SAB + d SB + d RB + S A      (2)

The time difference between clocks A and B can be determined from equations 1 and 2 by differencing the individual simultaneous TIC readings with the result shown below.

As can be seen most of the path delays tend to cancel. However, there is no reason for the transmit and receive delays of the earth station equipment to cancel perfectly since they are caused by physically different pieces of equipment. This area is one of the major sources of instability and inaccuracy in the two-way technique. The satellite delays, d SAB and d SBA , may perfectly cancel since in some cases the same satellite transponder is used for both directions. In other cases different transponders are used and then the cancellation is not perfect. The up and down link paths are physically the same, but the propagation delay is not exactly the same if the up and down link frequencies are different. This is generally the case.

For Ku-band the up link is normally at 14 GHz and the down-link is at 11 GHz. Therefore the effect of the ionosphere is not the same. However, the tropospheric delay will cancel to a large extent since it does not depend strongly on frequency. Another advantage of this two-way technique is that the signal to noise ratio is favorable. Antenna reflectors of one or more meters diameter are normally used at the ground stations, as shown in the photograph. These highly directional antennas also reduce multipath.

The stability of TWSTFT over a 24 hour period is better than 1 ns and has been observed to be as low as 100 picoseconds in some systems. TWSTFT systems can be calibrated to the 1 ns level, but this requires a portable earth station.

For questions or more information contact Victor Zhang at [email protected] .

Time Synchronization

The Root of All Timing: Understanding root delay and root dispersion in NTP

February 25, 2021 by Douglas Arnold 2 Comments

Five Minute Facts About Packet Timing

If you examine an NTP packet you will see the fields root delay and root dispersion.  See the diagram from RFC 5905 in Figure 1 bellow, which defines NTP version 4, the current version.

You might ask what is with all this “root” stuff?  Root in this case refers to the root of the time distribution spanning tree.  The root is a stratum 1 NTP server.  Something that usually has a GNSS receiver to get UTC.  If you are particularly fond of tree analogies, you can think of higher stratum NTP servers as branches, and clients as the leaves. 

The root delay is the round-trip packet delay from a client to a stratum 1 server.  This is important because it gives a crude estimate of the worst-case time transfer error between a client, or higher stratum server acting as a client, and a stratum 1 server.  In fact, it is the worst-case contribution to the time transfer error due to network asymmetry , if all of the round-trip delay was in one direction and none in the other direction.  Okay some of the network delay has to be in each direction, but this is an upper bound. The root delay is also used in clock steering algorithms to identify false tickers, that is servers with bad time or one’s that are sitting on the other side of a highly asymmetric network path. So, it is important. 

The root dispersion tells you how much error is added due to other factors.  One factor is the error introduced by a client due to the inaccuracy of its clock frequency.  Using NTP the higher stratum can set its clock to the lower stratum server, but if its clock frequency is off, then an error is introduced.

Recall that an NTP time transfer involves four timestamps as shown in Figure 2.

From the four timestamps the offset of the client with respect to the server is known and the round-trip delay from the client to the server and back. 

Offset = [(t2 + t3) – (t4 + t1)]/2

Delay = (t4 -t1) – (t3 – t2)

Dispersion = DR * (t4 – t1) + timestamping errors

Where DR is the drift rate of client clocks time and is equal to the fractional frequency error.  The timestamping errors term includes things like the errors due to the finite resolution of the clock, and delays in reading the clock when fetching a timestamp. The sum of root dispersion and half the root delay is called the root distance and is the total worse case timing error accumulated between the stratum 1 server and the client.

When a client gets time from a higher stratum receiver the root delay is the sum of the delays from all of the client-server pairs in the timing spanning tree.  In the case when a client is getting time from multiple servers, the best root delay is used.  This applies to root dispersion as well.  An example is shown in Figure 3.

Okay so you are ready to amaze your friends with your mastery of NTP root delays and root dispersion.

If you have any questions about packet timing, don’t hesitate to send me an email at  doug.arnold@meinberg-usa.com , or visit our website at  www.meinbergglobal.com .

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Related posts:

• NTP Monitoring
• Network Time Security (NTS): Updated security for NTP
• Leap Second Test
• The virtues of clock watching: Why it’s important to monitor your timing network

May 30, 2023 at 9:44 am

Why do root servers (stratum 1) have zero dispersion? While a refclock probably has no dispersion by definition, the clock following the refclock is not perfect. Similarly for root delay: Even when the refclock is the “perfect time”, doesn’t the startum-1 server has to communicate with the refclock, introducing some non-constant delays?

June 1, 2023 at 9:28 pm

You are correct that a real implementations of stratum 1 servers are not perfect. However the definitions for root delay and root dispersion in the RFCs that define versions of NTP do not include any imperfections in stratum 1 servers. In practice, it is nearly always true that the limitations of the server are negligible compared to the delay and dispersion contributions from the network.

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What is a round-trip flight?

It's one of the first decisions we make when booking a flight: Should I book a round-trip or a one-way flight?

It's typically something you'll think about before you ever click "search" to find flights and airfare.

At face value, it seems like a pretty straightforward choice. Book a one-way flight if you're only flying in one direction, and book a round-trip flight if you'll be returning home ... right?

Unfortunately, it's not quite that simple. Thanks to airline pricing trends and our own personal scheduling quirks, there's a bit more to consider.

There may be cases where you wonder if you're better off booking two one-way flights to save money. You may have uncertain plans that make it difficult to commit to a return flight. In some cases, when visiting a few different cities, you may be better off with something different entirely: a multicity itinerary.

There are also plenty of additional considerations if you're booking an award flight using frequent flyer miles or flying internationally.

Here, we break down the basics of what you need to know about booking round-trip flights.

A round-trip flight is an itinerary from one destination to another, with a flight back to the original destination.

In most cases, this is what you probably book when going on vacation or visiting a family member for a holiday weekend.

Let's say I live in Charlotte and want to fly to Arizona for a spring break trip. I book an itinerary with an outbound flight to Phoenix Sky Harbor International Airport (PHX) and a return trip to Charlotte Douglas International Airport (CLT) aboard American Airlines.

The two flights, booked together on a single itinerary, constitute a round trip.

What is the difference between a round-trip flight and a one-way flight?

When you book a round-trip flight, your itinerary includes an outbound flight and a return trip.

A one-way flight only takes you one direction — say, from Charlotte to Phoenix — with no return flight scheduled.

Is a round-trip flight different from 2 one-way flights?

Yes, in terms of how you book your trip. No, in terms of your travel plans themselves.

Again, a round-trip itinerary includes both an outbound flight and a return trip to the city of origin. A one-way flight is a single trip from one airport to another, with no return booked.

Booking 2 one-way flights

However, if you book two one-way flights, you can, in essence, create your own version of a round trip. This could be on the same airline or on two entirely different airlines.

For the purposes of your travel experience, it's effectively a round trip.

But, know that in the airline computer system(s), you'd technically be traveling on two separate reservations. So, you'd receive different trip confirmation numbers for the outbound and return flights.

Is booking 2 one-ways cheaper than a round-trip flight?

In the U.S., splitting a round trip up into two one-way flights on the same airline and travel dates typically makes no difference in terms of price.

However, on a small number of routes, airlines do charge a premium for one-way bookings compared to the price they charge for a round trip. This is more common internationally, where round-trip flights can be a better value than two one-way trips. Booking two separate one-way flights tends to be more expensive for international travel.

Also, budget carriers frequently offer one-way fares at the same price as a round-trip ticket.

That means if you booked separate one-way flights, you'd most likely end up paying the same as, or even more than, a round-trip fare, depending on the route.

Booking 2 one-way flights on different airlines

On the other hand, there are cases where, thanks to a tool like Google Flights , you might discover that you can save money by booking an outbound, one-way flight on one airline and a one-way return flight on a different airline.

For example, last year, TPG contributor Sean Cudahy needed to travel to North Texas for the weekend. Round-trip flights on a single airline from the Washington, D.C., region to Dallas Fort Worth International Airport (DFW) were coming in at more than $600 that particular weekend.

However, he saved a couple hundred dollars by mixing and matching: He booked a one-way, outbound flight to DFW aboard Delta Air Lines and a separate, one-way return flight on American Airlines.

Just keep in mind this can be risky. If your flight on one airline gets significantly delayed — to the point that you miss your return flight — your second airline won't automatically rebook you. The airline staff may not have much sympathy for your situation since your troubles happened aboard a different carrier.

Can I book a round-trip flight to 1 city and then return home from another?

Yes. These flights are known as open-jaw or multicity itineraries. Many airlines offer this booking option.

Let's say I want to fly from Newark Liberty International Airport (EWR) to Orlando International Airport (MCO). I'm going to visit Walt Disney World for a few days. Then, I'm going to take a Brightline train to South Florida and spend a few days at the beach before flying back to New York.

Since these are airports heavily served by JetBlue, I'll use that carrier as an example. On JetBlue's website, I'll select "Multi-city" instead of searching "Roundtrip" or "One-way" flights.

I'll need to separately enter each leg of the trip. Let's do a Saturday departure from Newark to Orlando, and then a Thursday return from Fort Lauderdale/Hollywood International Airport (FLL) to Newark.

You'll end up booked on a single itinerary, with the outbound and return flights linked, but with the different city combinations.

Can I buy a round-trip flight with an open return?

No, not exactly. When you book a round-trip flight, you'll generally have to specify a return leg and date.

If your plans are likely to change, though, what you'll want to do instead is pick a date that's far enough out. You'll need to book with an airline or in a cabin class that doesn't charge change fees. Then, reschedule your return trip once your plans are set. Alternatively, you can book a "flexible" fare, which is more expensive but generally allows easier changes.

Make sure you're familiar with an airline's change-fee policy before booking an open-return round-trip flight. For example, most airlines won't let you cancel or change basic economy tickets.

Should I book mileage or award tickets as 2 one-ways or a round trip?

It largely depends on the route. In some cases, you'll get better award availability if you book two one-way flights. In others, the taxes for two one-way award flights could end up being higher than what you'd pay for a round-trip itinerary.

However, in most cases nowadays, award tickets for two one-way flights and a round-trip flight tend to add up to the same number of miles. Just be sure to check both on an airline's website to ensure you're getting the best possible award availability .

Related reading:

• When is the best time to book flights for the cheapest airfare?
• The best airline credit cards
• What exactly are airline miles, anyway?
• 6 real-life strategies you can use when your flight is canceled or delayed
• Maximize your airfare: The best credit cards for booking flights
• The best credit cards to reach elite status
• What are points and miles worth? TPG's monthly valuations

Editorial disclaimer: Opinions expressed here are the author’s alone, not those of any bank, credit card issuer, airline or hotel chain, and have not been reviewed, approved or otherwise endorsed by any of these entities.

Local election results: Relief for Sunak in key mayoral race - but Labour wins in PM's backyard

The Tories have suffered some historic losses in Thursday's local elections, while Labour also claimed a big victory in the Blackpool South by-election. But in a relief for the prime minister, the Tory mayor of Tees Valley will keep his job.

Friday 3 May 2024 17:05, UK

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• Labour wins mayoralty in PM's own backyard
• Relief for PM as Tory mayor clings on in key race
• But Sunak admits overall results are 'disappointing'
• Tories could be 'almost annihilated' at general election
• Starmer hails Labour wins - but admits Gaza cost him votes
• And party admits fears over London mayoral result to come
• Vote 2024: Council results in full  | Mayoral results as they happen
• Live reporting by Katie Williams , Andy Hayes and (earlier)  Ben Bloch

  A special edition of our flagship weeknight politics show  Politics Hub With Sophy Ridge  will be live on Sky News from 7pm.

The fast-paced programme dissects the inner workings of Westminster, with interviews, insights, and analysis - bringing you, the audience, into the corridors of power.

Sophy will be joined by Work and Pensions Secretary Mel Stride , Labour's shadow home secretary Yvette Cooper , Reform leader Richard Tice , Lib Dem Helen Morgan , and elections analyst Michael Thrasher .

And on her panel tonight will be:

• James Starkie , former Home Office adviser;
• Caroline Flint , former Labour MP and minister.

Watch live on Sky News, in the stream at the top of this page, and follow live updates here in the Politics Hub.

Sir Keir Starmer has hailed Labour's victory in York and North Yorkshire as "an amazing moment in history".

Speaking after David Skaith's victory by almost 15,000 votes in Rishi Sunak's backyard, the Labour leader said while the party had seen "really good results" across the board, this was "a very, very special moment".

North Yorkshire is becoming less Conservative, Labour's winning mayoral candidate has said.

The area, which has elected a mayor for the first time, contains Rishi Sunak's constituency of Richmond.

Labour has historically struggled to compete in parliamentary elections there.

David Skaith took 35.1% of the vote for Labour - ahead of Conservative candidate Keane Duncan's 27.3%.

Asked what his victory means in a "very Conservative area", Mr Skaith replied: "I think in traditional terms it has been [very Conservative], but obviously not now."

'I'm willing to work with PM'

He added: "I think the really big thing is actually we've really made it about York in North Yorkshire because that's what this role is about. 

"It's really about the place in the region itself, and we've really got out on the doorstep and spoken to people and they've really, really enjoyed that message that we're fighting for York, North Yorkshire."

Asked about working with the prime minister, Mr Skaith said: "I look forward to working with him. 

"If he's willing to work, then I'm willing to work with him."

Keane Duncan admitted: "It's been tough. It's difficult out there right now."

He added: "We've got to reflect, we've got to rebuild."

With big swings being seen elsewhere, it's no change for another three councils.

The Lib Dems have kept Three Rivers , losing one seat to the Green Party.

In Solihull , the Conservatives have lost a seat but kept control with an overall count of 30.

And Labour holds Calderdale after gaining two seats, while the Tories lost four.

We've a few more results to bring you now - with all of the country's main parties failing to gain control of three councils.

The biggest loss was seen by the Conservatives in Basingstoke and Deane - it's down eight seats there, with Labour gaining one and four going to other parties.

In Sheffield , Labour gained two seats but at 35 to the Lib Dems' 25, there's no overall control there.

And in Norwich , the Green Party gained two seats from Labour.

Labour leader Sir Keir Starmer's stance on the war between Israel and Hamas in Gaza has been a "factor" in the party's local election results, its national campaign co-ordinator has said.

Sir Keir has admitted it's cost the party votes in some areas - and of course the issue helped George Galloway to win the Rochdale by-election earlier this year.

In February, Sir Keir called for a "ceasefire that lasts" in Gaza.

In November, however, his decision to favour "humanitarian pauses" led to the departure of 10 shadow ministers and parliamentary aides who rebelled to back a full ceasefire.

Labour has lost control of OIdham Council after gains were made by independents.

It was put to Mr McFadden that that result may have been because of Labour's stance on Gaza.

He replied: "I think it is a factor in some parts of the country, and I understand why people feel strongly about this. 

"Thousands of innocent people have been killed. People want it to stop.

"They want to do something about it. And if there's a case in parts of the country where we've lost support on that issue then we will work hard to regain it."

He says Labour's position is Israel has "a right to defend itself", but that the Palestinian people need a "better future".

It will be a "foreign policy priority" for Sir Keir if he becomes PM.

It's been going all Labour's way in the council election results today, and the party has now lost control of Kirklees.

The West Yorkshire authority has been shorn of five Labour councillors and three Tories - with the Lib Dems up two, the Greens up one, and independents up five.

It leaves the council under no overall control.

We won't get the result from the London mayoral contest today, but it's certainly one of the most prominent contests from this week's elections.

Sadiq Khan is hoping to stay in post, but faces a challenge from the Conservative candidate Susan Hall.

It's been an incendiary race, with Ms Hall accused of divisive politics.

Earlier this week, Labour's Wes Streeting said her winning would be a victory for "racists, white supremacists, and Islamophobes".

Challenged on this assessment by Sophy Ridge, Mr Streeting made no apologies for what he described as "grubby" Tory tactics.

"If people don't like Sadiq, fair enough," he said.

"If people oppose his policies, like ULEZ, fair enough.

"This is a democracy, that's what elections are about.

"But this mayor has received a scale of abuse and level of death threats that neither of his predecessors experienced."

Tory silence on racism 'deafening'

Mr Streeting also pointed to comments made about Mr Khan by Conservative-turned-Reform MP Lee Anderson, who claimed earlier this year that the capital had fallen under control of "Islamists".

The Labour frontbencher said such rhetoric had formed part of the Conservatives' campaign for the London mayoralty.

He added: "The silence from the Tory party about the racism in their ranks has been deafening.

"It shouldn't be left to senior Muslims (like former ministers Sajid Javid and Baroness Warsi) to call it out."

Mr Streeting admitted Labour feared a "close" race in London, and blamed changes to the voting system which meant those who voted for other left-centre parties like the Lib Dems and Greens could no longer choose someone like Mr Khan as a second preference.

He said while he understands frustrations with the system, a vote for a smaller party or independent candidate risked seeing Ms Hall end up in City Hall by the end of the weekend.

Mark Harper described the loss of two Essex councils to no overall control as "disappointing" as he learnt the news live on air with Sky News.

The Conservative Party lost two seats in Brentwood and 12 in Basildon, which it had regained from no overall control in 2021.

Speaking to Sophy Ridge during our Politics Hub special programme, the transport secretary said "it's always disappointing when you lose hard-working Conservative councillors".

'Clearly not good'

On the Tories' big loss in Basildon - a council the party typically does well in and where Labour gained six seats - he said "it's clearly not a good result" but added that it means the Conservatives "have to focus on the job at hand".

" There's one task for the Conservative Party to focus on, which is to get behind the prime minister, focus on the general election… and set out a clear set of arguments for the voters about what we've done."

Mr Harper said he was "not pretending" that the results of the latest round of elections were good for his party.

Continuing the flurry of significant results - here's a particularly bruising one for the Conservatives.

Labour has won control of Nuneaton and Bedworth - with the previously incumbent Tories losing a whopping 14 councillors.

Labour gained 15 overall.

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