Today’s VoIP technology usually delivers good quality audio, but there can be occasions when you want to check some aspects of its performance. The efficiency of VoIP can be affected by issues with your router, the behaviour of your ISP, network traffic or by codec conflicts. However, there are some useful tests you can run for yourself.
Broadband speed tests
Really, anyone with a broadband account should be using these tests from time to time. It’s well known that broadband providers frequently don’t deliver the speeds they promised. The time of day and your distance from the provider’s servers have significant effects, and some ISP’s have been known to throttle traffic for their own convenience. If you have calculated the broadband package you need to support a multi-line VoIP system, but your ISP doesn’t deliver, that’s something you should know about.
A speed test will give you two figures – upload speed and download speed. Although web browsing consists almost entirely of downloading, a VoIP telephone call is dependent on both. Most speed tests are free and Cloud-based, so you need only navigate to a hosted webpage to use them. If you are disappointed by the results, many of the hosting sites also rate the performance of alternative ISPs.
You can find speed tests on the pages of Ookla, FreeOla, Ping-test and Bandwidth Place to name a few.
Line quality tests
In addition to speed (data throughput), you also want stability and reliability. If your connection corrupts, drops or delays packets, it can introduce a variety of problems into VoIP calls. The two main parameters to look out for are jitter and latency.
Jitter refers to the range of variation in the time it takes packets to flow between the endpoints. You don’t notice jitter when you’re downloading a file but high jitter is damaging to real-time activities including VoIP and video calls.
Latency is a measure of the total time it takes data to travel between the two communicating endpoints (typically a round trip). It is a better measure as to how the whole network performs for VoIP than a simple broadband speed test.
You can find these quality tests hosted by FreeOla, MegaPath, and Voiptoners. If you discover you have line quality problems, ask a VoIP wholesale carrier such as IDT for advice.
Some sites are now hosting tools specifically crafted to test internet telephony services. They do this by passing simulated VoIP traffic across the network instead of just test packets. To use them and get meaningful results you will need to enter more information about your VoIP service. Details you may need include the number of VoIP lines you operate, the type of connection you use (DSL, cable, ISDN) and your location.
To help you interpret the results, the test pages provided by 8×8 and OnSIP provide benchmarks and easy to understand visual comparison tools. Visualware’s test collection also allows you to investigate your firewall, video transmissions and IPTV.