[Serusers] SER 0.8.12, Polycom 300, and ignored CANCEL messages

[Jamin W. Collins]

On Sat, Nov 13, 2004 at 06:56:04PM -0700, Jamin W. Collins wrote:
> Anyone else seeing problems with Polycom 300 phones ignoring CANCEL
> messages from a SER proxy?  I've got a number of SER proxies (running
> 0.8.12) that are receiving CANCEL messages and passing them on to the
> Polycom phone, but all indications are that the phone is just ignoring
> them (as it continues to ring).

I reported this problem a while ago as you can see from the quoting
above.  Since then, I believe the problem has been located.  It seems
that for some reason SER is inserting a "branch" tag to the INVITE sent
to the phone and then changing that "branch" tag on the disconnect:

The original INVITE request from the server:
        To: <sip:18742 at 172.16.22.25>
            SIP to address: sip:18742 at 172.16.22.25
        From: "Interaction Center" <sip:xxxxxxxxxx at DMN1.ORG;type=ICConnectionCall>;tag=17919
            SIP Display info: "Interaction Center" 
            SIP from address: sip:xxxxxxxxxx at DMN1.ORG
            SIP tag: 17919
        Via: SIP/2.0/UDP 130.110.72.16
        Call-ID: 6f1a95c1a4d7ba6d8ae12aeeda933906 at 130.110.72.16
        CSeq: 1 INVITE
        Contact: <sip:xxxxxxxxxx at 130.110.72.16;type=ICConnectionCall>
        User-Agent: ININ-EICSRVR01-99924257
        Allow: INVITE, BYE, ACK, CANCEL, OPTIONS, REFER, SUBSCRIBE, NOTIFY, MESSAGE, INFO
        Accept: application/sdp
        Accept-Encoding: identity
        Content-Length: 0

INVITE request from SER to phone (note the branch tag):
        Max-Forwards: 10
        Record-Route: <sip:18742 at 172.16.22.25;ftag=17919;lr=on>
        To: <sip:18742 at 172.16.22.25>
            SIP to address: sip:18742 at 172.16.22.25
        From: "Interaction Center" <sip:xxxxxxxxxx at DMN1.ORG;type=ICConnectionCall>;tag=17919
            SIP Display info: "Interaction Center" 
            SIP from address: sip:xxxxxxxxxx at DMN1.ORG
            SIP tag: 17919
        Via: SIP/2.0/UDP 172.16.22.25;branch=z9hG4bK4722.88643d91.0
        Via: SIP/2.0/UDP 130.110.72.16
        Call-ID: 6f1a95c1a4d7ba6d8ae12aeeda933906 at 130.110.72.16
        CSeq: 1 INVITE
        Contact: <sip:xxxxxxxxxx at 130.110.72.16;type=ICConnectionCall>
        User-Agent: ININ-EICSRVR01-99924257
        Allow: INVITE, BYE, ACK, CANCEL, OPTIONS, REFER, SUBSCRIBE, NOTIFY, MESSAGE, INFO
        Accept: application/sdp
        Accept-Encoding: identity
        Content-Length: 0

CANCEL message from the server:
        To: <sip:18742 at 172.16.22.25>
            SIP to address: sip:18742 at 172.16.22.25
        From: "Interaction Center" <sip:xxxxxxxxxx at DMN1.ORG;type=ICConnectionCall>;tag=17919
            SIP Display info: "Interaction Center" 
            SIP from address: sip:xxxxxxxxxx at DMN1.ORG
            SIP tag: 17919
        Via: SIP/2.0/UDP 130.110.72.16
        CSeq: 1 CANCEL
        Call-ID: 6f1a95c1a4d7ba6d8ae12aeeda933906 at 130.110.72.16
        User-Agent: ININ-EICSRVR01-99924257
        Content-Length: 0

CANCEL message from SER to phone (note the new value of the branch tag):
        Max-Forwards: 10
        Record-Route: <sip:18742 at 172.16.22.25;ftag=17919;lr=on>
        To: <sip:18742 at 172.16.22.25>
            SIP to address: sip:18742 at 172.16.22.25
        From: "Interaction Center" <sip:xxxxxxxxxx at DMN1.ORG;type=ICConnectionCall>;tag=17919
            SIP Display info: "Interaction Center" 
            SIP from address: sip:xxxxxxxxxx at DMN1.ORG
            SIP tag: 17919
        Via: SIP/2.0/UDP 172.16.22.25;branch=z9hG4bK4722.98643d91.0
        Via: SIP/2.0/UDP 130.110.72.16
        CSeq: 1 CANCEL
        Call-ID: 6f1a95c1a4d7ba6d8ae12aeeda933906 at 130.110.72.16
        User-Agent: ININ-EICSRVR01-99924257
        Content-Length: 0

In the initial INVITE request from the SER proxy to the phone the branch
tag had a value of "z9hG4bK4722.88643d91.0" while in the CANCEL message
bares a value of "z9hG4bK4722.98643d91.0" the digit immediately
following the first '.' is different.

Anyone know if there is a patch to correct this, an option to disable
the usage of the branch tag, or if this has been corrected post 0.8.12?

-- 
Jamin W. Collins

"Never underestimate the power of very stupid people in large groups."
-- John Kenneth Galbraith