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ATA Web user guide
70 / 114
2015/1/8
Item Description
The count formula of SIP Expire Time:
General: SIP Expire Time-[(SIP Expire Time/30)*6] as SIP
Expire Time > 60 seconds, if SIP Expire Time < 60 seconds, the
SIP Expire Time subtract 5 seconds uniformly.
1/2: SIP Expire Time * 1/2.
2/3: SIP Expire Time * 2/3.
3/4: SIP Expire Time * 3/4.
4/5: SIP Expire Time * 4/5.
5/6: SIP Expire Time * 5/6.
6/7: SIP Expire Time * 6/7.
7/8: SIP Expire Time * 7/8.
8/9: SIP Expire Time * 8/9.
9/10: SIP Expire Time * 9/10.
SIP Registration
Retry Timer
Default: 64 seconds.
Set up the period of registering SIP Server again if LP399 fails to
register SIP Server or IP-PBX server.
This column can only enter numbers; maximum length is 4 bytes
with the range of 5~3600 (seconds).
SIP Session
Timer T1
Default: 1000 ms; Set up round-trip time (RTP) estimate.
This column can only enter numbers; maximum length is 4 bytes
with the range of 500~2000.
*This function must be supported by Server.
SIP Session
Timer T2
Default: 8000 ms.
Set up the maximum retransmit interval for non-INVITE
requests and INVITE responses.
This column can only enter numbers; maximum length is 5 bytes
with the range of 4000~16000.
*This function must be supported by Server.
SIP Session
Timer B, F, H
Default: 32000 ms.
Set up the maximum retransmit interval for non-INVITE
requests and INVITE responses.
This column can only enter numbers; maximum length is 6 bytes
with the range of 8000~128000.
B: 64 * SIP T1; INVITE transaction timeout timer
。
F: 64 * SIP T1; non-INVITE transaction timeout timer
。
H: 64 * SIP T1, Wait time for ACK receipt.
*This function must be supported by Server.
For example, if T1 is 500 ms, T2 is 4 seconds and B,F,H is 32
seconds, then non-INVITE retransmissions occur at intervals of
500 ms, 1s, 2s, 4s, 4s, 4s, 4s, 4s, 4s, 4s. This means that
retransmissions occur with an exponentially increasing interval
that caps at T2. In this particular scenario, there are 10
retransmissions which is a total of 11 requests from UAC.
SIP INVITE
Timeout
Default: 30000 ms; Set up SIP Invite, If how long do not
respond, enter the failed state. This column can only enter