Yealink SIP-T2 SERIES Administrator's Manual page 764

Administrator's Guide for SIP-T2 Series/T19(P) E2/T4 Series/CP860 IP Phones
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)
X ranges from 1 to 16 (for SIP VP-T49G/SIP-T48G/T46G/T29G)
X ranges from 1 to 12 (for SIP-T42G)
X ranges from 1 to 6 (for SIP-T41P/T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
X is equal to 1 (for SIP-T19(P) E2/CP860)
Web User Interface:
Account->Advanced->Keep Alive Type
Phone User Interface:
None
account.X.nat.udp_update_time
Description:
Configures the keep-alive interval (in seconds) for account X.
X ranges from 1 to 16 (for SIP VP-T49G/SIP-T48G/T46G/T29G)
X ranges from 1 to 12 (for SIP-T42G)
X ranges from 1 to 6 (for SIP-T41P/T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
X is equal to 1 (for SIP-T19(P) E2/CP860)
Example:
account.1.nat.udp_update_time = 60
Note: It works only if the value of the parameter ―account.X.nat.udp_update_enable‖ is
set to 1, 2 or 3.
Web User Interface:
Account->Advanced->Keep Alive Interval(Seconds)
Phone User Interface:
None
742
Parameters Permitted Values
Integer from 15 to
2147483647
Default
30