[SIPForum-discussion] urgent 491
雨 陈
chen.yu26 at yahoo.com.cn
Wed Mar 19 06:48:54 UTC 2008
Hi, Herve and all,
Now I am recording the SIP call flowing, but there is a problem about the response 491 .
The call flowing as follows:
UA1 UA2 TIME
Both way RTP Media
ç==========================è
[254]INVITE[SDP]
ç-------------------------- 09:18:31:052
[255]INVITE[SDP]
----------------------------è 09:18:31:065
[256]100
----------------------------è 09:18:31:065
[257]491
----------------------------è 09:18:31:065
[259]100
ç------------------------------------- 09:18:31:071
[260]491
ç------------------------------------- 09:18:31:071
[261] ACK
ç---------------------------- 09:18:31:071
[263]ACK
-----------------------------è 09:18:31:085
[2639] INVITE [SDP]
---------------------------------------è 09:19:01:092
…………
As we can see, the session has already set up and the entire message in this flow have the same dialog-ID. Now both UA1 and UA2 re-invite each other just simultaneously, then they get 491 as response from the other one. Well, after 30s, the UA1 send a INVITE again which is NO.2639 with SDP. My question is :
1. Since no relevant message during the 30s space time, does the NO.2639 INVITE still belong to the call flow ?
2. Is the response 491 like 487, which means the existed session will be terminated?
In fact, the RFC3621 have just mentioned the UAC should start a timer when it received a 491 response, but not described what will happen, if the timer fires and the UAC don’t attempt the re-INVITE once more.
I look forward to the answer urgently,anything is helpful !
RE
Nora
---------------------------------
雅虎邮箱传递新年祝福,个性贺卡送亲朋!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20080319/812c43aa/attachment-0002.html>
More information about the discussion
mailing list