Yealink T5 Series, Administrator'S Manual

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Administrator’s Guide for SIP-T58V/T58A/T56A/CP960 IP Phones
410
Default 0
Web UI Account->Advanced->Retransmission
[1]
X is the account ID. For T58V/T58A/T56A, X=1-16; for CP960, X=1.
SIP Session Timer
SIP session timers T1, T2 and T4 are SIP transaction layer timers defined in RFC 3261 . These session timers are con-
figurable on the phones.
Timer T1
Timer T1 is an estimate of the Round Trip Time (RTT) of transactions between a SIP client and SIP server.
Timer T2
Timer T2 represents the maximum retransmitting time of any SIP request message. The re-transmitting and doubling of
T1 will continue until the retransmitting time reaches the T2 value.
Example :
The user registers a SIP account for the IP phone and then set the value of Timer T1, Timer T2 respectively (Timer T1: 0.5,
Timer T2: 4). The SIP registration request message will be re-transmitted between the IP phone and SIP server. The re-
transmitting and doubling of Timer T1 (0.5) will continue until the retransmitting time reaches the Timer T2 (4). The
total registration request retry time will be less than 64 times of T1 (64 * 0.5 = 32). The re-transmitting interval in
sequence is: 0.5s, 1s, 2s, 4s, 4s, 4s, 4s, 4s, 4s and 4s.
Timer T4
Timer T4 represents that the network will take to clear messages between the SIP client and server.
Topic
SIP Session Timer Configuration
SIP Session Timer Configuration
The following table lists the parameters you can use to configure the SIP session timer.
Parameter sip.timer_t1 <y0000000000xx>.cfg
Description
It configures the SIP session timer T1 (in seconds).
T1 is an estimate of the Round Trip Time (RTT) of transactions between a SIP client and SIP server.
Permitted
Values
Float from 0.5 to 10
Default 0.5
Web UI Settings->SIP->SIP Session Timer T1 (0.5~10s)
Parameter sip.timer_t2 <y0000000000xx>.cfg
Description
It configures the SIP session timer T2 (in seconds).
Timer T2 represents the maximum retransmitting time of any SIP request message.
Permitted
Values
Float from 2 to 40