There are many codecs for audio, video, fax and text. Below is a list of the most common codecs for VoIP. As a user, you may think that you have little to do with what these are, but it is always good to know a minimum about these, since you might have to make decisions one day relating codecs concerning VoIP in your business; or at least might one day understand some words in the Greek VoIP people speak! I wont drag you into all the technicalities of codecs, but will just mention them.
If you are a techie and want to know more about each one of these codecs in detail, have a look there.
Common VoIP Codecs
|G.711||64||Delivers precise speech transmission. Very low processor requirements. Needs at least 128 kbps for two-way.|
|G.722||48/56/64||Adapts to varying compressions and bandwidth is conserved with network congestion.|
|G.723.1||5.3/6.3||High compression with high quality audio. Can use with dial-up. Lot of processor power.|
|G.726||16/24/32/40||An improved version of G.721 and G.723 (different from G.723.1)|
|G.729||8||Excellent bandwidth utilization. Error tolerant. License required.|
|GSM||13||High compression ratio. Free and available in many hardware and software platforms. Same encoding is used in GSM cellphones (improved versions are often used nowadays).|
|iLBC||15||Robust to packet loss. Free|
|Speex||2.15 / 44||Minimizes bandwidth usage by using variable bit rate.|