Jitter is defined as “slight irregular movement, variation or unsteadiness.” That may sound a lot like you before your morning cup of coffee, but imagine how jitter sounds (literally) when it comes to your VoIP calls. The answer: not good.
In the world of VoIP, jitter is one of the most common causes of poor QoS and audio. Whether you consider yourself a jitter expert or beginner, here are answers to five common (and not-so-common) questions about jitter that you can learn from or pass along:
What is jitter?
In short, jitter is any deviation in, or displacement of, voice packets. This deviation or displacement can happen either while packets are in transit or when they arrive at their destination. Out-of-order packets of any kind will always produce choppy and/or distorted audio.
What are some common signs of jitter?
There are several obvious signs of jitter, as well as some that can go undetected. If you’re seeing your display monitor flickering, a processor in your desktop or server acting up or (most notably) unexpected problems with your audio signals, chances are jitter is the culprit.
Why does jitter happen?
At the end of the day, the cause of jitter is really the cause of packet deviation or displacement. This can happen for several reasons—for example, codec or phase timing mismatching. You can learn more about jitter causes here.
How can I measure any jitter I find?
If you’d like to measure and/or analyze your jitter to infer insights and make actionable improvements, there are several tools available to do so. For example, you can use a Bit Error Rate Tester, a Jitter Analyzer, a Counter Timer or a Spectrum Analyzer. There are also free tools like Wireshark that allow you to monitor data directly at the packet level. Any of these tools can be helpful.
How can I resolve/prevent jitter?
Our best recommendation would be a jitter buffer, which temporarily stores arriving packets in order to minimize the delay or “scrambling” of packets while they’re en route to their destination.
The more you know, the better you’ll be able to protect your network and voice traffic. Check out this blog to learn how to identify (and resolve) other leading causes of poor VoIP call quality.