Command Reference Guide

38 ● compression 3Com Router 5000 Family and Router 6000 Family
Command Reference
compression
Purpose Use the compression command to configure the voice coding method according to
priority level.
Use the
undo compression command to restore the default value.
Syntax compression { 1st-level | 2nd-level | 3rd-level | 4th-level } {
g711alaw | g711ulaw | g723r53 | g723r63 | g729a | g729r8 | g729ab |
g729br8 | g726r16 | g726r24 | g726r32 | g726r40 }
undo compression { 1st-level | 2nd-level | 3rd-level | 4th-level }
Parameters 1st-level
Indicates the first selected voice compression method.
2nd-level
Indicates the second selected voice compression
method.
3rd-level
Indicates the third selected voice compression method.
4th-level
Indicates the fourth selected voice compression
method.
g711alaw
Specifies G.711 A-law coding (defining the pulse code
modulation technology), requiring the bandwidth of
64 kbps, usually adopted by Europe.
g711ulaw
Specifies G.711ì-law coding, requiring the bandwidth
of 64 kbps, usually adopted in the North America and
Japan.
g723r53
Specifies G.723.1 Annex A coding, requiring the
bandwidth of 5.3 kbps.
g723r63
Specifies G.723.1 Annex A coding, requiring the
bandwidth of 6.3 kbps.
g729a
Specifies G.729 Annex A coding (a simplified version
of G.729 coding), requiring the bandwidth of 8 kbps.
g729r8
Specifies G.729 (the voice coding technology using
conjugate algebraic-code-excited linear-prediction)
coding, requiring the bandwidth of 8 kbps.
g729ab
Adds G.729 Annex B coding on the basis of G.729a.
g729br8
Specifies G.729 Annex B coding, requiring the
bandwidth of 8 kbps. This coding supports voice
activity detection (VAD), discontinuous transmission
(DTX), and comfort noise (CNG).
g726r16
Specifies G.726 Annex A coding. It uses the adaptive
differential pulse code modulation (ADPCM)
technology, requiring the bandwidth of 16 kbps.
g726r24
Specifies G.726 Annex A coding. It uses ADPCM,
requiring the bandwidth of 24 kbps.
g726r32