Yealink SIP-T54S Administrator's Manual page 141

Setting Up Your System
Details of Configuration Parameters:
Parameters Permitted Values Default
account.X.nat.udp_update_enable 0, 1, 2 or 3 1
Description:
Configures the type of keep-alive packets sent by the IP phone to the NAT device to keep
the communication port open so that NAT can continue to function for account X.
0-Disabled
1-Default (the IP phone sends UDP packets to the server)
2-Options (the IP phone sends SIP OPTIONS packets to the server)
3-Notify (the IP phone sends SIP NOTIFY packets to the server)
If it is set to 0 (Disabled), the IP phone will not send keep-alive packets.
X ranges from 1 to 16 (for SIP-T54S/T48G/T48S/T46G/T46S/T29G)
X ranges from 1 to 12 (for SIP-T52S/T42G/T42S)
X ranges from 1 to 6 (for SIP-T41P/T41S/T27P/T27G)
X ranges from 1 to 3 (for SIP-T40P/T40G/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
X is equal to 1 (for SIP-T19(P) E2/CP860/CP920)
Web User Interface:
Account->Advanced->Keep Alive Type
Phone User Interface:
None
Integer from 15 to
account.X.nat.udp_update_time 30
2147483647
Description:
Configures the keep-alive interval (in seconds) for account X.
X ranges from 1 to 16 (for SIP-T54S/T48G/T48S/T46G/T46S/T29G)
X ranges from 1 to 12 (for SIP-T52S/T42G/T42S)
X ranges from 1 to 6 (for SIP-T41P/T41S/T27P/T27G)
X ranges from 1 to 3 (for SIP-T40P/T40G/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
X is equal to 1 (for SIP-T19(P) E2/CP860/CP920)
Example:
account.1.nat.udp_update_time = 30
Note: It works only if the value of the parameter "account.X.nat.udp_update_enable" is set
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