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Spectralink 84-Series Series Wireless Telephones Administration Guide
1725-86984-000_P.docx
September 2016
240
Algorithm
Reference
Raw Bit
Rate
IP Bit Rate
Sample
Rate
Default
Payload
Size
Effective
Audio
Bandwidth
G.711 a-law
RFC 1890
64 Kbps
80 Kbps
8 Ksps
20 ms
3.5 KHz
G.711
RFC 1890
64 Kbps
80 Kbps
16 Ksps
20 ms
7 KHz
G.722.1
RFC 3047
16 Kbps
24 Kbps
32 Kbps
32 Kbps
40 Kbps
48 Kbps
16 Ksps
20 ms
7 KHz
G.729a
RFC 2833
8 Kbps
24 Kbps
8 Ksps
10 ms
8 KHz
Caution: New Zealand requirements
Re: The Optimum Packet Size for transmission through the Public Switched
Telephone Network (PSTN)
Because of the extensive delay already experienced when calling cellular and
international networks, Telecom Access Standards recommends the use of either
10 or 20mS packet length when passing packets through the PSTN. The use of
G.711 codecs and 10 or 20mS packet length is critical to maintaining delay times
which comply with PTC220 requirements for Customer Equipment (<50mS).
Note: Network Bandwidth Requirements for Encoded Voice
The network bandwidth necessary to send the encoded voice is typically 5-10%
higher than the encoded bit rate due to packetization overhead.
Use the parameters in the following table to specify the priority for audio codecs on your
Spectralink handsets.
Table 11-3: Audio Codec Priorities
Parameter
Permitted Values
Default
voice.codecPref.G711_A
voice.codecPref.G711_Mu
voice.codecPref.G722
voice.codecPref.G7221.16kbps
voice.codecPref.G7221.24kbps
voice.codecPref.G7221.32kbps
voice.codecPref.G729_AB
0 to 27
7
6
4
0
0
5
8
The priority of the codec. If 0 or Null, the codec is disabled. A value of 1 is the highest priority. If a handset does
not support a codec, it will treat the setting as if it were 0 and not offer or accept calls with that codec.
Band Steering
Band steering is a feature that allows you to configure the handsets to use a preferred band
during roaming.