Oftentimes, I hear people mention bandwidth when speaking about VoIP QoS (Quality of Service). There seems to a common misconception that bandwidth is the key factor in determining the quality of voice over a network. In reality, this is not true. It's of course important to have enough bandwidth for your VoIP needs, but there are other important qualities of your Internet connection that affect VoIP QoS -- packet loss, latency, and jitter.
The Internet works by breaking up all data into small groups called packets. Occasionally, some of these packets are lost in the network and don't reach the far-end. This is called packet loss and results in degradation to the quality of your phone call. Ideally, you would want packet loss to be 0% (or at least under 1%), however it's possible for you to experience acceptable VoIP quality with packet loss as high as 5%.More