Network latency in the Internet connection is the number one enemy of network administrators. But what can you do on a network where the latency can be such that it makes it difficult? The first step is to find and measure network latency. Only then will you be able to do something about the delay. To help you, we have compiled a list of tools control and network response time metrics that can help you.
Before we get started, we will try to explain what network latency is and what it causes in networks. It will help you better understand how the various tools work. We will also look at the importance of latency and how it affects network usage. Next, we will look at how we can measure network latency. And since it is useless to find and measure network latency without further action, we will also analyze ways to reduce it. The following is a list of the best network latency testing tools.
What is network latency?
Network latency, or network response time, is the amount of time it takes for a data packet to travel from its source to its destination. In an ideal world, there would be zero delay. But in reality, there is always a delay. And although latency is inevitable, it must always be ensured that it does not become so significant that it begins to affect the normal operation of a network.
Several factors contribute to the delay. First, there is the time of propagation. Although networks are fast and bits travel at the speed of light (through fiber optics), it takes some time to reach their destination. And the longer the path, the more time they will need. For this reason, the latency between two computers that are thousands of miles apart will normally be higher than that between computers in the same room.
Another factor that contributes to the phenomenon is transmission delay. This is a delay that may be due to the medium itself. It also comes from the size of the data packets. Larger packages will have a higher delay as they take longer to deliver.
The router itself, as well as other delays due to any data processing, are also a source of network latency. Even in simple networks where queues are absent, each router must first handle its data and then make deliveries.
In fact, many more delays than mentioned above can affect data transmission. Imagine the delay due to the queue that occurs when data cannot be sent immediately or due to storage when it needs to be saved to disk or memory and then retrieved.
Delay measurement
Measuring latency can be more complicated than it looks. This is especially true when measuring latency between very distant points. It is mainly due to the fact that even the huge delay is practically relatively small, of the order of a few milliseconds. You can not call your friend at the other end and say "Okay, I'll send you a package, tell me when it will arrive" and just measure the delay. Chances are the package will arrive before you finish talking.
Usually, the delay is measured by sending a package back to the sender and by measuring the time it takes for the response to arrive. This cyclic travel time is considered as network latency. There are some disadvantages of this method of evaluation. For example, if the return path is different, the network latency number will not tell you which of the sending or return paths is delayed.
Another possible issue is that the types of packets used to measure response time (standard ICMP requests and responses) are not always treated by network devices with the same priority as some other network traffic.
Why is the delay important?
The answer here is obvious. Because when the network latency is very high, it can affect the usability of the networks. Unusually high response time is often a sign that something is wrong with the network. Most of the time, it will be the result of some congestion. Networks are like highways and when there is too much traffic, things slow down and so you have a lot of network latency.
But measured latency is not always a sign of a network problem. Since we usually measure latency by measuring travel time, another source of latency can be the remote device. If this device is too busy doing other tasks, it may not respond immediately to the ICMP request received from the test host. When this happens, it will be perceived as the network response time, but in reality it has nothing to do with the network and measuring the network response will not enlighten you about the problem.
And it's not the only delay that may have nothing to do with the network. Various applications usually delay network traffic. When servers are overloaded then they respond more slowly. Just like networks when they are congested. But the delay of the server and running applications, it is not theme us today.
Reduce network latency
When you are faced with high network latency you should first measure it and then reduce it. There are several ways to do this. It usually depends on what is causing it. And since the most common cause of high response time on a network is network overuse, let's see what can be done about it.
The circuits of a network are not unlimited and when they are exceeded, congestion occurs and users realize long delays. It works just like traffic. This is especially true for WAN circuits which often have very limited bandwidth.
So to reduce latency, the best way is, as you may have already guessed, to reduce network usage. But of course, this is not always possible. What you can usually do is optimize your usage. For example, setting rules and limits on each user's packages, asking for files to be compressed before being transferred, etc. But this is a different matter from today.
The best tools for measuring response time
As you already know, to fix high network latency problems, you must first measure it and find out where it comes from. Various tools can help here. Some of them will just measure the delay, while others will help you find it. You will also find some that measure bandwidth usage, which can help, as we know that overuse is the main cause of high network latency. The tools are grouped by type and not preferably.
1 - SolarWinds Network Performance Monitor (FREE trial)
SolarWinds is one of the most well-known manufacturers of network management tools. The company was and remains famous for its multiple free tools, which cater to the specific needs of network administrators.
The SolarWinds Network Performance Monitor or NPM is SolarWind's flagship product. Arguably one of the best SNMP bandwidth monitoring tools out there. The advantage of the tool is rather its simplicity. The dashboards, views, interletterand reports can be fully customized to your preferences or needs. The tool can be set up in minutes and can handle from the smallest networks to huge ones with thousands of devices.
However, NPM will not directly measure network latency. But giving you detailed information about bandwidth usage in any part of your network will allow you to quickly identify problem areas where congestion could cause high latency.
NPM uses the SNMP protocol to periodically check your devices and read their interface meters, calculate bandwidth usage and display it as graphs. The tool configuration only requires you to specify the IP address of a device and the community string. Advanced features let you create network maps and display the critical path between two devices, a great feature for troubleshooting latency.
Pricing for the Network Performance Monitor starts at € 2.410,00. However they have the option of a free trial for 30 days which is reasonably enough time to solve the problem on a network you manage.
2 - SolarWinds NetFlow Traffic Analyzer (FREE Trial)
Another great product from SolarWinds, the NetFlow Traffic Analyzer, can give administrators a more detailed picture of network traffic. It will not only show you the use and possible delay, but it will also show you where it occurs and often what causes it. The tool provides detailed information on data traffic. For example, the tool will let you know which type of traffic or which user is consuming the most bandwidth.
SolarWinds NetFlow Traffic Analyzer uses the NetFlow protocol to gather detailed usage information from network devices. The NetFlow protocol, originally developed by Cisco, allows devices to send detailed information about each "chat" or network stream to a NetFlow collector in an analyzer such as NetFlow Traffic Analyzer. This information contains several elements that can be used to analyze traffic. Many manufacturers, in addition to Cisco, also include NetFlow or equivalent software in their equipment, sometimes referred to by a different name. Recently, the NetFlow protocol has been standardized as IPFIX or IP Exchange Information Exchange by the IETF. SolarWinds NetFlow Traffic Analyzer works with all variants of this protocol, making it a great choice.
NetFlow Traffic Analyzer is an add-on that installs on the Network Performance Monitor. Pricing starts at € 1.560,00 and varies depending on the number of servers. And in this there is a trial version lasting 30 days.
3 - Paessler PRTG
Grapher Traffic Tracker Paessler, or PRTG, is a bandwidth tracking tool. And it's one of the easiest and fastest programs to set up. Paessler claims that it can work in minutes and really, the installation of the product does not take much time, although a little longer than it claims. The product has an automatic detection feature, which means that it will scan your network on its own and automatically add the devices it finds.
PRTG comes standard with many interfaces, allowing you to choose the one that best suits your needs. There is a native Windows console application, there is also an interface based on Ajax and there are applications for Android and iOS mobiles. It generally makes great use of the capabilities of each platform. For example, mobile applications will allow you to access any component of your device by scanning a QR code tag embedded in it.
PRTG uses a combination of network monitoring technologies. It uses SNMP for monitoring, but also WMI for Windows devices, as well as NetFlow and Sflow, two similar but competing streaming analytics technologies. This tool has various sensors designed specifically for measuring network latency. It has a QoS sensor that will measure latency in a full back-and-forth, a Cisco IP SLA sensor and a Ping sensor.
4 - ManageEngine NetFlow Analyzer.
ManageEngine NetFlow Analyzer is a NetFlow-based monitoring tool with some advanced network response time monitoring features.
The tool provides a detailed picture of network usage and traffic. The web-based desktop of the program will allow you to view network traffic from applications, chats, protocols and more. The completeness of the program tools is one of its best features. It offers flexibility and allows you to include the data you want. It also provides available mobile applications.
ManageEngine NetFlow Analyzer supports many streaming technologies, such as NetFlow, IPFIX, J-flow, NetStream and others. As a bonus, it also integrates well with Cisco devices, with customization of traffic configuration and / or QoS policies directly from the tool.
And to measure latency, this tool has a WAN Round Trip Time (RTT) display that lets you monitor WAN availability, latency, and quality of service.
There is a minimal free version, and the full versions give you the option of a free trial for 30 days.
5 - PingPlotter
Despite its misleading name, PingPlotter is actually a Traceroute-type graphic software that can help solve network problems. This diagnostic tool records the latency and packet loss between your computer and a target. It allows you to visualize information, speeds up the troubleshooting process and can help present a case if as an administrator you need to convince someone that there is a problem.
PingPlotter records network performance on each hop between the computer running it and a website, server, or target device. The tool will control the path to any device that is accessible from the network. Shows where the delay occurs, saving you a lot of time.
While performance statistics are useful, they only tell you if the network failed - or failed - during the test and where the failure is. PingPlotter has an built-in feature that can show you exactly when an issue occurs. This allows you to distinguish between a complete failure throughout the test and a short period of a serious failure. It can also help correlate failure with other concurrent events.
It also has a minimal free version and two paid versions, the standard and the Pro. The Pro version has the option of a free trial for 15 days.
6 - MultiPing
MultiPing is also a product with a somewhat misleading name. Although it mainly uses Ping to do its job, MultiPing is really a tracking system, much like SolarWinds NPM. Of course, using Ping instead of SNMP means that the information you get will be very different. Do not expect to see bandwidth usage with this tool. One thing you will see though, is the delay. And just as your bandwidth displays show bandwidth graphs over time, this program will plot the latency over time.
MultiPing will show you packet loss both in percentage and in minimum, average and maximum network response time. Setting it up is a very easy task. The user interface of the product can be configured according to your preferences, placing the different components in the positions you want. The system also has a notification feature when the parameters are out of range and the ability to start various programs after notification.
7 - Ping
You do not need to download or install anything to try network latency ping. Ping is a command that is integrated into most modern operating systems. In short, Ping sends a series of ICMP echo requests to a targeted IP address and waits to respond with corresponding ICMP echo responses. The delay between the request and the response is called a round-trip delay or pure delay. And when it fails to get an answer to one of its requests, ping assumes that either the request or the answer was lost along the way and compiles the packet loss information.
8 - Traceroute (or Tracert)
Similarly, the Traceroute (or Tracert) command, if coming from the Windows world, can also be used for network response tests. This is another command that is embedded in most operating systems. It uses the same type of ICMP requests and responses as Ping, but does so in a way that allows the user to individually control the response time - or latency - of each network segment along the route. It is even better than Ping as it can give you a very good idea of where most of the network latency is happening. Therefore, this tool can not only measure but also detect the delay.
