Specifications

Administrator’s Guide for SIP-T2xP IP Phones
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The corresponding attributes of the codec are listed as follows:
Codec
Configuration Methods
Priority
RTPmap
PCMU
Configuration Files
Web User Interface
1
0
PCMA
Configuration Files
Web User Interface
2
8
G729
Configuration Files
Web User Interface
3
18
G722
Configuration Files
Web User Interface
4
9
G723_53
Configuration Files
Web User Interface
0
4
G723_63
Configuration Files
Web User Interface
0
4
G726_16
Configuration Files
Web User Interface
0
112
G726_24
Configuration Files
Web User Interface
0
102
G726_32
Configuration Files
Web User Interface
0
99
G726_40
Configuration Files
Web User Interface
0
104
iLBC
Configuration Files
Web User Interface
0
102
Packetization Time
Ptime (Packetization Time) is measurement of the duration (in milliseconds) of the audio
data in each RTP packet sent to the destination, and defines how much network
bandwidth is used for the RTP stream transfer. Before establishing a conversation,
codec and ptime are negotiated through SIP signaling. The valid values of ptime range
from 10 to 60, in increments of 10 milliseconds. The default ptime is 20ms. You can also
disable the ptime negotiation.