The Tools Needed for VoIP Troubleshooting, Part One: Packet Sniffers
September 2, 2015
In a perfect world, VoIP calls would always be crystal-clear in terms of audio quality. But this is not a perfect world and, in fact, VoIP systems are notorious for being unreliable and poor in quality.
While the callers on each side are stuck having to exclaim, “I’m sorry I couldn’t hear you; can you repeat that,” IT technicians have to work expediently to perform VoIP troubleshooting—a feat that can feel complex.
Many times, this is due to the fact that IT professionals will pick up the wrong tool to correct the obstacle at hand. After all, there are many VoIP troubleshooting tools available on the market, each with a specific purpose. But, if you select the wrong one, it can lead to an incorrect network diagnosis and thousands of dollars of unneeded repairs or upgrades. What’s more, the underlying issues leading to poor VoIP quality will still be present.
In the coming weeks, this series will shed some light on a few of these commonly-used tools, detailing which should be used for which problem. Today, we will begin by discussing the packet analyzer, also known as a packet sniffer or packet capture:
Why you use it: A packet analyzer is a program used to observe data packets as they flow across the network. An analyzer can confirm that a bottleneck is occurring on the network, thus proving that a problem is in fact occurring on the network.
What it’s good for: A packet analyzer is handy for confirming packet loss during data transfers. It can also confirm that there are issues related to the contents of a packet (like missing QoS tags) or an application. For instance, you could use an analyzer to gain feedback about session ports, as well as possible issues with the source and destination of an IP addresses.
What it’s bad for: Using a packet analyzer only gives you a high-level view. It’s like trying to determine the root cause of a traffic jam by standing on top an overpass and counting the cars below. You’ll be able to confirm, in other words, that there are hundreds of cars jammed onto the highway. But you won’t be able to see what’s actually causing the traffic jam (like a jackknifed tractor trailer two miles down the road).
Likewise, a packet analyzer will be able to confirm that there is a problem, but provide little insight into the root cause of the problem. It won’t be able to report issues in the physical, data-link or network layers or provide any feedback related to your bandwidth or device limitations.