http://voip.ms/faq.php#whatcodecs


^Codec ^Bit Rate ^Nominal Ethernet Bandwidth (Kilobits) |
|G.711 |64 Kbps |87.2 Kbps |
|G.729a |8 Kbps |31.2 Kbps |
|GSM |13 kbps |29.2 kb/s |


http://voip.ms

http://www.callcentric.com

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