ITU G.729

G.729 is an ITU standard codec.
Has two main flavors: A and B, see the ITU G series page for more info.

It offers toll quality speech at a reasonably low bit rate of 8Kbps. However, it is a rather "costly" codec in terms of CPU processing time, therefore some VoIP phones and adapters (notably the Linksys/Sipura/Cisco brands) can only handle one G.729 call (channel) at a time. This can cause calls to fail if the user attempts to use three-way calling, or place simultaneous calls on both lines of a two-line device, and G.729 is the only allowed codec.

Use of this codec in a product requires licensing. Licenses can be purchased from a company that re-sells G.729 licenses such as:

There are some free for non-commerical experimental use implementations for G.729

VOIP Phone Support

This codec is supported by at least the following phones:
  • ACT P104SLD IP Phone - SIP IP phone
  • Cisco ATA 186 - analogue phone adapter (limited to 1 channel)
  • Cisco 79XX - hard phone
  • Firefly - IAX softphone (with external DLL)
  • Grandstream BudgeTone 100 series IP phones
  • Sipura SPA-841 VOIP phone
  • Sipura SPA-2000 - analogue phone adapter (limited to 1 channel)
  • Sipura SPA-2002 - analogue phone adapter (limited to 1 channel)
  • Sipura SPA-3000 ATA
  • SNOM phones - SIP IP phone (ie. SNOM190)
  • X-Pro
  • Zyxel P2000W V2
  • Polycom IP 301/330/601
  • Linksys RTP300 and WRTP54G
  • C470IP and C475IP from Siemens

Other Resources

Asterisk server supports it in pass-thru or with a license

Created by: jht2, Last modification: Thu 07 of Apr, 2011 (13:12 UTC) by steelmans1980
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