How to quickly monitor the latency of your network with PRTG

 Originally published on July 30, 2020 by Patrick Gebhardt
Last updated on January 23, 2024 • 7 minute read

Latency is a very crucial key element that contributes to the speed of any network. The term refers to a measurement of the time it takes for a data packet to travel between two points. This is often called "latency" or "round-trip time," and a low latency network connection is one that generally experiences small delay times – a high latency connection generally suffers from long delays. Not keeping latency spikes to a minimum will endanger the reliability of a whole network. When latency is too high, problems with VoIP and video conferences are likely to arise; furthermore, transmission errors can prevent images from loading. So it's clear that latency issues might push the capacities of any IT department to the limit, present challenges for entire business strategies and can become a serious concern.

Latency is always expressed in milliseconds and there are two metrics that express latency. The most known measure of latency is called "round trip time" (RTT); this is the time it takes for a packet to get from one point on the network to another. The alternative measurement is called "time to first byte" (TTFB); this records the time difference between the moment the first part of a packet left and the time that it arrived at the destination.

Nothing you should live with

If sysadmins experience high latency, that's for sure nothing they should live with: Monitoring and testing can be the answer. A latency test is like the little brother of a comprehensive monitoring. You will gain insights about problems that may exist. However, these are always selective and without concrete significance; in the end, you don't really know where a solution should start.

A monitoring solution like PRTG is able to always keep an eye on all QoS parameters. Latency, packet loss, jitter, and the Mean Opinion Score are monitored literally all the time. So if something goes wrong, you will get notified at once. PRTG is able to simultaneously monitor servers, routers, and switches, so you can immediately recognize the causes of latency issues or other network problems.

Sensors are the fuel for our monitoring experience

In PRTG, sensors are the basic monitoring elements. And when it comes to latency, we have more than one good solution; here are just three examples of sensors that will help you to deal with latency issues:

  • The PRTG Ping sensor checks the availability of your devices, while the dashboard lets you see if everything is OK in your network. You can read more about ping in a follow-up article that will be published on our blog in the coming weeks.
  • Many Cisco devices gather their own QoS values. The Cisco IP SLA sensor reads these values and adds them to your centralized monitoring statistics.
  • PRTG comes with several QoS sensors. These include the QoS (Quality of Service) Round Trip sensor, which measures the quality of service along an entire route. (This sensor causes problems for some customers. We are working on it and ask you to report any problems to our support team. Each monitoring setup is individual, and once we know the specific situation and objectives, we can offer more productive advice or workarounds.)



Getting curious and fancy a good last piece of information? PRTG can be tested for 30 days with full functionality and without paying a single cent. After the trial period has expired, your installation automatically reverts to the freeware edition with a limit of 100 sensors. Our trial is installed quickly and provides reliable solutions for all kinds of latency problems within minutes. 👇