Cisco IP Phone 6851

Step 3
Click Submit All Changes.
Configure the RTP Parameters
Procedure
Step 1
In the phone web user interface, navigate to Admin Login > advanced > Voice > SIP.
Step 2
In the RTP Parameters section, set the Real-Time Transport Protocol (RTP) parameter values as described
in RTP Parameters, on page 163.
Step 3
Click Submit All Changes.
Configure the SDP Payload Types
Configured dynamic payloads are used for outbound calls only when the Cisco IP Phone presents a Session
Description Protocol (SDP) offer. For inbound calls with an SDP offer, the phone follows the caller’s assigned
dynamic payload type.
The Cisco IP Phone uses the configured codec names in outbound SDP. For incoming SDP with standard
payload types of 0-95, the phone ignores the codec names. For dynamic payload types, the phone identifies
the codec by the configured codec names (comparison is case-sensitive).
Procedure
Step 1
In the phone web user interface, navigate to Admin Login > advanced > Voice > SIP.
Step 2
In the SDP Payload Types section, set the value as specified inSDP Payload Types, on page 164.
• AVT Dynamic Payload—Any nonstandard data. Both sender and receiver must agree on a number.
Ranges from 96 to 127. Default: 101.
Step 3
Click Submit All Changes.
Cisco IP Phone 6800 Series Multiplatform Phones Administration Guide
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SIP and NAT Configuration