Yealink SIP-T2XP Administrator's Manual page 201

Parameters
Description:
Configures the session timer of T4 (in seconds) for account X.
T4 represents the maximum duration a message will remain in the network.
X ranges from 1 to 6 (for SIP-T28P).
X ranges from 1 to 3 (for SIP-T26P/T22P).
X ranges from 1 to 2 (for SIP-T20P).
Web User Interface:
Account->Advanced->SIP Session Timer T4 (2.5~60s)
Phone User Interface:
None
To configure session timer via web user interface:
1. Click on Account.
2. Select the desired account from the pull-down list of Account.
3. Click on Advanced.
4. Enter the desired value in the SIP Session Timer T1 (0.5~10s) field.
The default value is 0.5s.
5. Enter the desired value in the SIP Session Timer T2 (2~40s) field.
The default value is 4s.
6. Enter the desired value in the SIP Session Timer T4 (2.5~60s) field.
The default value is 5s.
7. Click Confirm to accept the change.
Configuring Basic Features
Permitted Values Default
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