It's easy and convenient to integrate your phone lines with your Internet connection. This is one of the reasons why VoIP is becoming more and more popular along with the added flexibility and streamlining of communications. However, one of the downsides of VoIP is that you have to pay attention to your network. Building your own VoIP infrastructure is a complicated business and requires consider technical know how in addition to significant investment. In addition to the technical complexes, one needs to monitor the bandwidth pretty regularly to ensure that there's enough space for VoIP to operate.
As a retail customer, it's important to know how much bandwidth you need to maintain for VoIP. Most of us have more than enough for our personal consumption and we'll first focus on bandwidth management strategies for home users. For the most part, it's pretty simple. Almost everyone has used Skype to make voice calls and it's easy to get by with even a dial up modem. Skype's encoding changes depending on the speed of the connection and if your download / upload speed is a minimum of 10 KB / s, you should be able to make basic calls.
Of course, more bandwidth is always better and if you give Skype a chance, it will utilize the higher bandwidth in oder to give you better voice clarity, fewer jitters in the speech and an overall better experience. If you're using a VoIP service such as that provided by Vonage for example, you have to call them and find out what bandwidth requirements must be met.
Businesses using VoIP have to play by an entirely different set of rules. It's not enough for the quality to be "just enough." It has to be at least as good as the voice over a regular telephone network and we have various ways of measuring that. It's safe to say that you need around 20 KB / s Internet speeds both ways for each person who will be immediately to be on the safe side.
This means that businesses need to manage their networks accordingly – probably by creating virtual LANs to segregate the traffic and monitor the bandwidth on a regular basis. Most of your VoIP headaches can be solved when you migrate to a Hosted PBX system, but bandwidth management is something you'll still have to do on your own. It's the only downside to what is otherwise a win win situation for everyone.