Cisco SPA962-NA Administration Guide - Page 21

Codec Voice Compression, Algorithm, Description, digitized speech. Linksys supports G.729. G.729A is - compatibility

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Chapter 1 Introducing Linksys 900 Series IP Phones Feature Descriptions The administrator can select the low-bit-rate codec used for each line. G.711a and G.711u are always enabled. Table 1-3 describes the codecs supported by the Linksys SPA900 Series IP phones. Table 1-3 Codecs Supported by Linksys SPA900 Series IP Phones Codec (Voice Compression Algorithm) G.711 (A-law and mµ-law) G.726 G.729A G.723.1 Description This very low complexity codec supports uncompressed 64 kbps digitized voice transmission at one through ten 5 ms voice frames per packet. This codec provides the highest voice quality and uses the most bandwidth of any of the available codecs. This low complexity codec supports compressed 16, 24, 32, and 40 kbps digitized voice transmission at one through ten 10 ms voice frames per packet. This codec provides high voice quality. The ITU G.729 voice coding algorithm is used to compress digitized speech. Linksys supports G.729. G.729A is a reduced complexity version of G.729. It requires about half the processing power to code G.729. The G.729 and G.729A bit streams are compatible and interoperable, but not identical. SPA900 Series IP phones support the use of ITU G.723.1 audio codec at 6.4 kbps. Up to two channels of G.723.1 can be used simultaneously. For example, Line 1 and Line 2 can be using G.723.1 simultaneously, or Line 1 or Line 2 can initiate a three-way conference with both call legs using G.723.1. When no static payload value is assigned per RFC 1890, SPA900 Series IP phones can support dynamic payloads for G.726. Document Version 3.0 Linksys 900 Series IP Phone Administrator Guide 1-7

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1-7
Linksys 900 Series IP Phone Administrator Guide
Document Version 3.0
Chapter 1
Introducing Linksys 900 Series IP Phones
Feature Descriptions
The administrator can select the low-bit-rate codec used for each line. G.711a and G.711u are
always enabled.
Table 1-3
describes the codecs supported by the Linksys SPA900 Series IP
phones.
When no static payload value is assigned per RFC 1890, SPA900 Series IP phones can support
dynamic payloads for G.726.
Table 1-3
Codecs Supported by Linksys SPA900 Series IP Phones
Codec (Voice Compression
Algorithm)
Description
G.711 (A-law and mμ-law)
This very low complexity codec supports uncompressed 64
kbps digitized voice transmission at one through ten 5 ms
voice frames per packet. This codec provides the highest
voice quality and uses the most bandwidth of any of the
available codecs.
G.726
This low complexity codec supports compressed 16, 24, 32,
and 40 kbps digitized voice transmission at one through ten
10 ms voice frames per packet. This codec provides high
voice quality.
G.729A
The ITU G.729 voice coding algorithm is used to compress
digitized speech. Linksys supports G.729. G.729A is a
reduced complexity version of G.729. It requires about half
the processing power to code G.729. The G.729 and G.729A
bit streams are compatible and interoperable, but not
identical.
G.723.1
SPA900 Series IP phones support the use of ITU G.723.1
audio codec at 6.4 kbps. Up to two channels of G.723.1 can be
used simultaneously. For example, Line 1 and Line 2 can be
using G.723.1 simultaneously, or Line 1 or Line 2 can initiate
a three-way conference with both call legs using G.723.1.