1812-(01-06): Codec Type [System: VoIP: Profile (1-4): Codecs (1812): Codec]

For the selected VoIP profile, use this option to specify which CODECs the profile should support and in which order. There are six available CODEC types:
  • G.711
  • G.726
  • G.729AB
  • G.723
  • G.722
  • ILBC

DSX IP keysets support G.711, G.722, and G.729 CODEC types, and should normally connect using the CODEC listed first in the profile. The additional CODECs are for third-party SIP SLT compatibility. When setting up the connection, the system may have to work downward through the profile's CODEC list to find an acceptable setting. If the third-party SIP SLT can't negotiate a compatible CODEC, it won't connect.

The following table provides a very basic performance comparison of the supported CODEC types. For more details, see Cisco's Voice Over IP - Per Call Bandwidth Consumption site.

Basic CODEC Comparison
CODEC Bit Rate (Kbps)1 Mean Opinion Score (MOS)2 Bandwidth Requirement (Ethernet)3
G.711 64 Kbps 4.4 87 Kbps
G.726 32 Kbps 3.9 55.2 Kbps
G.729AB 8 Kbps 4.2 31 Kbps
G.723 6.3 Kbps 4.0 22 Kbps
G.722 64 Kbps 4.2 80 Kbps
ILBC 15 Kbps 4.1 27.7 Kbps
1 This is the rate at which audio is sampled during encoding into digital signals. In general, higher sample rates yield better voice quality.
2 MOS is a method of rating voice call quality as judged by actual humans (i.e., not calculated). A rating of 1 is poor; a rating of 5 is excellent. An MOS rating of less than 4 is often perceived as poor speech quality.
3 Bandwidth is a per-call network utilization statistic. You need enough bandwidth in your network to support the likely number of simultaneous IP calls.

Features Related to this Program

Telephone Features
IntraMail Features

Program Options

Option Description
00 [Default] None
01 G.711
02 G.726
03 G.729AB
04 G.723
05 G.722
06 ILBC