Is a measure of the capability of a network?
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Network availability refers to the operational status of a computer network and its ability to quickly make connections, process traffic, and respond to user requests. Show What Is Network Availability?Network availability, also known as network uptime, is a measure of how well a computer network—whether a local area network (LAN) or a wide-area network (WAN)—can respond to the connectivity and performance demands placed on it. Network availability is a key consideration in disaster planning, but it also has critical impacts on everyday life and work. For organizations, network downtime or sluggishness equates to business downtime, at considerable cost to organizations through inefficiency, lost sales, lack of critical data for decisions, and other harmful effects. For individuals, network availability ensures the ability to communicate with and interact with others, whether that’s through a cellular network text to a friend, an online purchase or streaming entertainment, or a call for emergency services. Network availability is calculated by dividing the uptime by the total time in any period. The goal is 100% availability, although another commonly referenced goal is known as “five nines,” or 99.999% availability. That’s the equivalent of only a few minutes of downtime in a year. A variety of measures, including WAN acceleration or optimization, may be undertaken to reach these goals. Why Is Network Availability Important?Network availability is a fundamental prerequisite for access to data and applications. It can be a key concern for enterprises that run multiple data centers, since users need to be able to access application servers and data everywhere with the best connections and fastest performance possible. How many times have you waited for service from a clerk or provider who struggled because their computer was “slow?” Without a highly available network, users can’t access the data and applications they need—or can’t do so quickly enough. At the extreme, a denial of service can result, leading to frustrated employees, unhappy customers, and lost business and goodwill. How Does Network Availability Work?Some of the many factors that can affect network availability include power supply or physical disruption (such as may be caused by natural disasters), component capacity and connection limits, component failures, and malicious attacks. In addition, when a network connects users with data spread across large geographical distances, latency becomes a significant factor in network performance. There are as many solutions as there are causes of disruption. For instance, because 100% availability is the target, many organizations incorporate redundancy and failover systems into their networks to ensure that if a component goes out of service, a backup takes over. Load balancers help to ensure that requests are distributed to the resources most able to quickly respond and helping to prevent any individual component from being overwhelmed. And the ability to easily and efficiently scale operations up or down to meet spikes in demand—including the capacity and security mitigations to withstand denial-of-service (DoS) attacks such as SYN floods, UDP floods, PUSH and ACK floods, and teardrop attacks—is frequently addressed through cloud services as well as through security solutions specifically designed to protect network availability. How Does F5 Ensure Network Availability?F5 BIG-IP DNS optimizes network availability for users and applications by monitoring the status of network components and routing users to the closest or best-performing physical, virtual, or cloud environment. When configured as a full-proxy device, it intercepts all DNS queries and hyperscales in response to distributed denial-of-service (DDoS) attacks, mitigating the attack and protecting the network infrastructure behind it. Whether deployed as hardware, virtual editions, or a cloud service, BIG-IP DNS provides “always on” availability.
At Obkio Network Performance Monitoring, we are a team of telecommunication experts specializing in performance monitoring. Over the years, we’ve had the opportunity to work and speak with IT professionals on the daily who are experiencing network issues. When we begin the discussion with clients about monitoring their network performance, the metric that we most commonly hear about is Network Speed. But in the network world as in life, size isn't everything, quality matters too. For example, just because you have a big Internet pipe, that doesn’t mean that it won't get congested or leak data packets. So, to be able to answer questions like:
You need to learn how to measure network performance with all of the key network metrics, and that's exactly what we'll be covering in this article. Before talking about measuring network performance, let’s quickly go over the vocabulary surrounding network monitoring. When we talk about traditional network monitoring, we often refer to Fault Monitoring or Device Monitoring. Network Device Monitoring refers to monitoring the use of network resources or network devices using SNMP monitoring protocol. For example, to monitor the state of a firewall or determine the CPU usage or bandwidth usage of an interface. In that case, we usually take measurements from a specific location in the network, such as the counter of an interface, a CPU, etc. This type of monitoring is good, and you should definitely keep doing it. But, the term network monitoring covers a vast range of techniques. It begins with device monitoring, but you can take it further by monitoring end-to-end user experience. Or NPM is end-to-end network monitoring of the end-user experience. It differs from traditional monitoring because performance it is monitored from the end-user perspective, and is measured between two points in the network. For example:
If there’s a problem with your Internet connection, you can't just monitor your devices to find your problem. You need to monitor the user experience to identify performance issues affecting your Internet connection. Just so we’re on the same page, we’re going to give you a quick definition of network performance. Network Performance is "the analysis and review of collective network statistics, to define the quality of services offered by the underlying computer network [that is] primarily measured from an end-user perspective." More simply, network performance refers to the analysis and review of network performance as seen by end-users. There are three important concepts in that definition: Before you can analyze and compare network performance measurements data over time, you must first measure key network metrics associated with network performance and collect a history of the data you’ve measured. Network Performance refers to the quality of the network. The quality will be different depending on where in the network the measurements are taken. For example, the quality of a network will not be the same if we compare the performance of a path from Montreal and New York vs a path from Montreal and Tokyo. The quality will also vary depending on when the measurements are taken. Therefore, your network performance may be great early in the workday when less users are online, and begin to degrade later on in the day when more users log on. The end-user experience is the most important factor when measuring network performance. But just hearing about the user experience isn't enough! With the right monitoring tools we can turn the user's experience into measurable metrics, and translate those measurements into areas for improvement. Now, let’s get to how to measure network performance! As mentioned above, to monitor the performance from a user point-of-view, we need to perform network performance tests from that same perspective. Ideally to do so, you want to monitor network performance from the end-user’s location without having to install a network measurement tool on each user workstation. Moreover, you don’t want to capture every data packet for analysis, which will require a lot of extra hardware and can intrude into your user’s privacy. When you want to measure network metrics, performance and historical, you can use temporary tools like traceroutes and pings to identify problems. This can give you insight into ongoing problems, but if you’re looking to troubleshoot intermittent network issues, you can’t use temporary tools. Essentially, if you end up identifying intermittent issues with periodic tools, you probably just got lucky that you used the tool exactly when the problem popped up again, or you may have actually caught a permanent issue. That’s why you need a tool that continuously monitors your network performance, and will notify you when an issue happens or when an intermittent network problem pops back up. You need a permanent, continuous network monitoring solution, like Obkio Network Monitoring Software. Get started with Obkio’s free trial and Getting Started Documentation.  Start Measuring Network Metrics Start monitoring network performance, measuring network metrics and troubleshooting network problems in with Obkio! Start for Free To begin measuring your network performance with Obkio, you need to deploy Monitoring Agents in all your key network locations. Monitoring Agents are a unique software like continuously monitor performance using synthetic traffic which simulates and monitors the end-user point-of-view. They also:
Once your Monitoring Agents are deployed, they will continuously exchange synthetic UDP traffic between each other to monitor performance, this is called a Network Monitoring Session. They will primarily measure performance by measuring key network metrics and displaying them on Obkio's Network Response Time Graph. When it comes to how to measure network performance, it’s important to know which network performance metrics you need to examine. Depending on the specific issues that affect your network, not every metric is going to be important for you to look at. But there are some metrics that are essential for any businesses to consider. Obkio's Network Monitoring tool continuously measure different operating parameters based on a variety of different network metrics, such as latency, jitter, packet loss, and more. This establishes a performance baseline based on the cumulative results of those metrics. Let’s go through the most essential network metrics that you should absolutely be monitoring: In a network, latency refers to the measure of time it takes for data to reach its destination across a network. You usually measure network latency as a round trip delay, in milliseconds (ms), taking into account the time it takes for the data to get to its destination and then back again to its source. Measuring the round trip delay for network latency is important when knowing how to measure network performance because a computer that uses a TCP/IP network sends a limited amount of data to its destination and then waits for an acknowledgement that the data has reached its destination before sending any more. Therefore, this round trip delay has a big impact on network performance. When measuring latency, consistent delays or odd spikes in delay time are signs of a major performance issue that can happen for a variety of reasons. Most delays are actually undetectable from a user’s perspective and can therefore go unnoticed but can have a huge impact when using VoIP, or unified communication systems such as Zoom, Skype, Microsoft Teams and so on. A network performance monitoring (NPM) solution is a great network latency monitor because it measures latency and can track and log these delays to find the source of the problem.
How to Measure Latency Learn how to measure network latency using Obkio’s Network Monitoring software to identify network issues & collect data to troubleshoot. Learn more When learning how to monitor latency, it's important to note that latency also affects maximum throughput of a data transmission, which is how much data can be transmitted from point A to point B in a given time. We’ll be covering throughput in point 4. But the reason that latency affects throughput is because of TCP (Transmission Control Protocol). TCP makes sure all data packets reach their destination successfully and in the right order. It also requires that only a certain amount of data is transmitted before waiting for an acknowledgement. A common analogy of the relationship is to imagine a network path like pipe filling a bucket with water. TCP requires that once the bucket is full, the sender has to wait for an acknowledgement to come back along the pipe before any more water can be sent. If it takes half a second for water to get down the pipe, and another half a second for the acknowledgement to come back, this equals a latency of 1 second. Therefore, TCP would prevent you from sending any more than the amount of data, or water in this example, that can travel in any one second period. Essentially, latency can affect throughput, which is why it’s so important to know how to check network latency.
How to Identify Network Problems & Diagnose Network Issues Learn how to identify network issues by looking at common problems, causes, consequences and solutions. Learn more To put it not so lightly, network jitter is your network transmission’s biggest enemy when using real-time apps such as unified communications, including IP telephony, video conferencing, and virtual desktop infrastructure. Simply put, jitter is a variation in delay. Otherwise known as a disruption that occurs while data packets travel across the network. There are many factors that can cause jitter, and many of these factors are the same as those that cause delay. One difficult thing about jitter is that it doesn’t affect all network traffic in the same way. Jitter can be caused by network congestion. Network congestion occurs when network devices are unable to send the equivalent amount of traffic they receive, so their packet buffer fills up and they start dropping packets. If there is no disturbance on the network at an endpoint, every packet arrives. However, if the endpoint buffer becomes full, packets arrive later and later. If you’ve ever been talking to someone on a video call or other unified communication system, and suddenly their voice speeds up significantly, then slows down to catch up, or keeps fluctuating between the two - you have a jitter problem. When measuring network jitter, remember that jitter can also be caused by the type of connection you use. A connection on a shared medium, such as a cable, is more likely to have higher jitter than a dedicated connection. So that’s something to keep in mind when choosing a connection medium.
How to Measure Jitter Learn how to measure network jitter using Obkio’s Network Monitoring software to identify network problems & collect data to troubleshoot. Learn more Packet loss refers to the number of data packets that were successfully sent out from one point in a network, but were dropped during data transmission and never reached their destination. It’s important for your IT team to measure packet loss to know how many packets are being dropped across your network to be able to take steps to ensure that data can be transmitted as it should be. Knowing how to measuring packet loss provides a metric for determining good or poor network performance. If you're wondering how to measure packet loss easily, a network performance monitoring software, like Obkio, uses a synthetic monitoring tactic which involves generating and measuring synthetic traffic in order to count the number of packets sent and the number of packets received. Packet loss is usually expressed as a percentage of the total number of sent packets.
Packet loss is something that is determined over a period of time.
How can you figure that out? Well that’s why Obkio calculates packet loss every minute, so you always get an up-to-date and precise measure of packet loss.
How to Measure Packet Loss Learn how to measure packet loss using Obkio’s Network Monitoring software to proactively identify problems in your network & collect data to troubleshoot. Learn more Throughput refers to the amount of data passing through the network from point A to point B in a determined amount of time. When referring to communication networks, throughput is the rate of data that was successfully delivered over a communication channel. Measuring network throughput is usually done in bits per second (bit/s or bps), "Internet Connection Speed" or "Internet Connection Bandwidth" is a general term used by internet companies to sell you high-speed internet, but is used by default to mean throughput, which is the actual rate of packet delivery over a specific medium. That’s why the best way to learn how to measure network throughput is to use Speed Tests. A Speed Test is the best solution for measuring network throughput to give you an idea of how fast your Internet connection is right now. Essentially, a speed test measures network speed by sending out the most amount of information possible throughout your network, and monitoring how long it takes to get delivered to its destination. A network performance monitoring solution like Obkio allows you to run speed tests manually, or schedule speed tests between monitoring Agents, or a group of multiple Agents to ensure your speed or throughput is constantly being monitored. Obkio also allows you to perform speed tests with multiple TCPs at the same time, which makes for the most accurate speed test results.
How to Monitor Network Speed Learn how to monitor network speed with Obkio Network Monitoring tool for end-to-end network monitoring and continuous network speed monitoring. Learn more In a simplified way, packet duplication refers to when data packets are duplicated somewhere in the network, and are then received twice at their destination. Many times, if the source of the data believes that a data packet was not transmitted correctly because of a packet loss, it may retransmit that packet. The destination source may have already gotten the first packet, and will receive a second duplicate packet. Once again, in the example of a video chat, packet duplication may cause you to hear as though someone is repeating words or sentences as they’re speaking to you - which isn’t a very pleasant experience. Packet reordering is also pretty self explanatory and occurs when data packets arrive at their destination in the wrong order. This can happen for various reasons, such as multi-path routing, route fluttering, and wrong QoS queue configuration. Packet reordering is also very simple to spot. If you’re talking to someone over video call and all of a sudden words in their sentences sound scrabbled and out of order, it may be because the data arrived in the wrong sequence. Once again, a network performance monitoring solution will be able to catch these problems, right as they happen. Having continuous monitoring of your network, whether from your head office, data center, or home office, means that you’ll catch these network issues long before you’re on an important video call with a client who can’t understand a word you’re saying because of packet loss or packet reordering.
How to Identify Network Problems & Diagnose Network Issues Learn how to identify network issues by looking at common problems, causes, consequences and solutions. Learn more Now you may be wondering how all these network performance metrics could possibly play a part in how to measure network performance. All the metrics we mentioned, in addition to user requirements and user perceptions, play a role in determining the perceived performance of your network. Each metric on its own gives you an idea of how your infrastructure is performing, but you need to look at all of these factors to give a true measurement of network performance. The best way to measure and quantify user experience is by measuring User Quality of Experience (QoE). Quality of Experience (QoE) allows you to measure performance from the end-user perspective and is essentially the perception of the user of the effectiveness and quality of the system or service. In fact, users base their opinions about the network exclusively on their perception of QoE. Measuring QoE is a culmination of all these network metrics we discussed, as well as the ability of the network to meet the user’s expectations. That’s basically what network performance is all about. Other network performance metrics you can use to measure QOE include: The MOS score was created by the ITU, a United Nations agency that sought to facilitate international connectivity in communications networks, and created a metric that could be measured and understood by all. The MOS has been originally developed for traditional voice calls but has been adapted to Voice over IP (VoIP) in the ITU-T PESQ P.862. The standard defines how to calculate a MOS score for VoIP calls based on multiple factors such as the specific codec used for the VoIP call. The MOS score is a rating from 1 to 5 of the perceived quality of a voice call, 1 being the lowest score and 5 the highest for excellent quality. You can learn more about MOS score in our article on Measuring VoIP Quality with MOS. VoIP quality refers to the quality of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet Obkio’s NPM software calculates the VoIP Quality for each network performance monitoring session every minute. Obkio measures VoIP Quality with MOS score even if there is no ongoing call, to provide a proactive monitoring over packet capture solution. Don't wait for bad user experience complaints to start network troubleshooting! This Quality of Experience (QoE) metric helps IT pros understand the complex impact of network performance on VoIP.
How to Measure VoIP Quality & MOS Score (Mean Opinion Score) Learn how to measure VoIP Quality using MOS Score (Mean Opinion Score) & Obkio’s VoIP monitoring solution to identify poor VoIP Quality issues & dropped calls. Learn more As you can see, there are a lot of factors to keep in mind when choosing how to measure network performance, and all them need to be monitored simultaneously to really provide a concrete conclusion. Lucky for you, the number one key to learning how to measure network performance is finding a solution that measures throughput, latency, packet loss, jitter, and more, to give you a simple and quick overview of your network. Obkio Network Monitoring is your personal network admin that continuously measures network performance metrics in real-time to help understand how they’re affecting your network’s performance. As soon as a problem occurs, with any of the metrics being measured, you’ll be notified - even before it reaches the end user. Start measuring network metrics! Start Measuring Network Performance Monitor your network performance and measure key network metrics with Obkio. Deploy in minutes with Obkio's 14-day free trial. Start for Free What is measurement in networking?For network performance measurement, throughput is defined in terms of the amount of data or number of data packets that can be delivered in a pre-defined time frame. Bandwidth, usually measured in bits per second, is a characterization of the amount of data that can be transferred over a given time period.
How is network capacity measured?How is network capacity measured? Network capacity measurements count the number of bits that pass down a link in each second. As volumes are high, the usual unit of measure is Megabits per second (Mbps). Recently, faster speeds have become so great that they are measured in Gigabits per second (Gbps).
What is used to measure network performance?Throughput: Throughput is a metric allowing you to measure the actual data transmission rate through different areas of your network. While bandwidth lets you set the theoretical limit of data transfer, throughput measures the actual amount of data packets successfully sent to the destination via the network.
What is capacity of a network?Network capacity is the maximum amount of data that can be reliably transferred between different locations over a network.
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