Cisco SPA301 Administration Manual page 35

Getting Started
Ensuring Voice Quality
Cisco Small Business SPA300 Series, SPA500 Series, and WIP310 IP Phone Administration Guide
Codec Complexity and Description
G.726 Low complexity. Supports compressed 16, 24,
32, or 64 kbps digitized voice transmission at
one to ten 10ms voice frames per packet. When
no static payload value is assigned per
RFC-1890, Cisco SPA IP phones can support
dynamic payloads for G.726.
G.726 is supported only for 32 kbps on the
Cisco SPA525G or Cisco SPA525G2.
G.729 and G.729A low-medium complexity. G.729 medium
G.729A complexity.
G.729A requires about half the processing power
of G.729. The G.729 and G.729A bit streams are
compatible and interoperable, but not identical.
G.723. 1 High complexity. Cisco SPA 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 use G.723. 1 simultaneously, or Line 1 or
Line 2 can initiate a three-way conference with
both call legs using G.723. 1 .
G.723. 1 is not supported on the Cisco SPA525G
or Cisco SPA525G2 or Cisco WIP310 phones.
G.722 Only one G.722 call at a time is allowed. If a
conference call is placed, a SIP re-invite
message is sent to switch the calls to
narrowband audio.
When a G.722 call is established, the Cisco SPA
IP phones display a HD Logo next to the call state.
This allows a caller to clearly differentiate
between a wide-band call and a narrow-band
call.
G.722 is not supported on the Cisco WIP310.
1
MOS
4. 1
(32 kbps)
4
3.8
4.3 (approx)
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