Voice over IP (VoIP) convergence means that most of us are running a variety of services over a single set of wires. Many IT groups, especially during new deployments, are ensuring that everything runs over a single Ethernet cable – data, voice, video, chat, system management, and more. The IT battle-cry of “Putting all your eggs in one basket, and then guarding that basket really well” is appealing because all of these services can indeed be delivered over one cable today.
But protecting that basket is a complex and multi-faceted challenge. Not long ago, one of two conditions existed for IT professionals in the networking field:
- The network is up
- The network is down
Today there are nearly infinite conditions between those two. The quality of the service delivered to each system must be adequate to support these ever-increasing demands. The most obvious place where issues reveal themselves is in VoIP communications.
Think about it. You likely don’t balk when a data transfer takes 25 minutes instead of 20. You don’t complain much when a video frame rate drops during a webcast. But the moment voice reception becomes suboptimal it is obvious and impactful. The voice comes in garbled blobs of sound and you can’t understand what the speaker is saying. But, “the network is up.”
Problems with VoIP are subtle and sinister. The factors that contribute to common VoIP problems include moderately complex concerns like optimal packet routing, traffic prioritization and traffic shaping, and network saturation. But there are also some less frequently understood components of networking that have a profound impact on VoIP. These components include codec, jitter, packet loss, and speed versus throughput.
In this article I’ll explain those terms in more details to demystify the factors that impact VoIP. I’ll also show some handy tools that help identify and measure these factors. These tools will empower you to identify the root cause, and potential resolution, of many common VoIP issues. These tools and techniques are often useful for debugging other streaming media issues as well, so you’ll be doubly armed.