[Users] Declined INVITE invokes multiple Decline's at Proxy

Augustin, Andrew (external) Andrew.Augustin at external.t-mobile.de
Wed Jul 12 13:26:22 CEST 2006


Hello, 

I am using openser v1.0. 

I have a problem with the following SIP scenario with openser: 

- A invites B to a call session, B declines the invitation 

The message trace shown below is just part of the message trace produced for
the above scenario displaying message frames in sequence F43, F44 ...
through F64

Initially everything works as expected: INVITEs, Trying (100) and Ringing
180 messages are routed correctly from A to B and from B to A via the
intermediate proxies (this is not shown below). While still 'Ringing', B
decline's the call (sends a Decline message) message: F44 in trace below.
This also initally routes OK. 

But the call flow for this scenario is expected to terminate at message: F55
once the 'Decline' has routed its way back from the B-Party to the A-Party
and a final 'ACK' is sent by the A-Party to the previous proxy: Proxy-1. 

But what actually occurs is that openser running on Proxy-1 automatically
resends a 'Decline' at message F56 identical to the 'Decline' it first sent
at message F46. This in turn prompts further ACKs and 'Decline's until it
finally times out at message F107 (not shown below). 

It appears that openser saves the original message and attempts to
retry/resend the 'Decline' message when prompted by an ACK. This continues
for several cycles with ACKs and Decline's being sent and received around
the system until a timeout occurs. 

The above behaviour also occurs for the following scenario: 

- A invites B to a call session, B responds with a Busy 

Can you help me to: 

- understand what is going on 
- terminate what appears to be an open 'transaction' for the 'Decline' and
prevent further 'Decline's and ACKs being sent around the system. 

Best regards, 
Andrew 

--------------

A-Party         Proxy-1         Proxy-2         Proxy-3         B-Party
10.1.195.134:50 10.1.195.134:50 127.0.0.1:5070  127.0.0.1:5080
10.1.195.208:50
|               |               |               |               |
|<nging 180 F43<|               |               |               |
|               |               |               |               |
|               |<----------------------------- Decline 603 F44<|
|               |               |               |               |
|               |>F45 ACK ------------------------------------->|
|               |               |               |               |
|               |>F46 603 Decline ------------->|               |
|               |               |               |               |
|               |<--------------------- ACK F47<|               |
|               |               |               |               |
|               |               |<cline 603 F48<|               |
|               |               |               |               |
|               |               |>F49 ACK ----->|               |
|               |               |               |               |
|               |               |>F50 603 Decli>|               |
|               |               |               |               |
|               |               |<----- ACK F51<|               |
|               |               |               |               |
|               |<------------- Decline 603 F52<|               |
|               |               |               |               |
|               |>F53 ACK --------------------->|               |
|               |               |               |               |
|<cline 603 F54<|               |               |               |
|               |               |               |               |
|>F55 ACK ----->|               |               |               |
|               |               |               |               |
|               |>F56 603 Decline ------------->|               |
|               |               |               |               |
|               |<--------------------- ACK F57<|               |
|               |               |               |               |
|<cline 603 F58<|               |               |               |
|               |               |               |               |
|>F59 ACK ----->|               |               |               |
|               |               |               |               |
|               |>F60 603 Decline ------------->|               |
|               |               |               |               |
|               |<--------------------- ACK F61<|               |
|               |               |               |               |
|<cline 603 F62<|               |               |               |
|               |               |               |               |
|>F63 ACK ----->|               |               |               |
|               |               |               |               |
|               |>F64 603 Decline ------------->|               |
|               |               |               |               |










-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.sip-router.org/pipermail/sr-users/attachments/20060712/e3378c4c/attachment.htm>


More information about the sr-users mailing list