I have written a module that choose the next client reading the destination from a db, but I can easily obtain the same scenario with the basic serial forking example:

 route{
        [...]
       t_on_failure("1");
       t_relay();
 }

 failure_route[1] {
       append_branch("sip:number1@mygw.com");
       log(1,"first redirection\n");
       t_on_failure("2");
       t_relay();
 }

 failure_route[2] {
       append_branch("sip:number2@mygw.com");
       log(1, "second redirection to the same gateway, but different number\n");
       t_relay();
 }



-----Messaggio originale-----
Da: Greger V. Teigre [mailto:greger@teigre.com]
Inviato: lun 07/05/2007 15.48
A: Zappasodi Daniele
Cc: serusers@lists.iptel.org
Oggetto: Re: [Serusers] sequential forking and merged request

Any device implementing UA functionality should follow RFC3261. But I'm
not sure how you manage to fork off two INVITEs to the same gateway? I
would start there.
g-)

Zappasodi Daniele wrote:
> Hello,
> I have a question about sequential forking and Merged Request.
> If in a forking SER calls two lines of the same client (different numbers and different Request-URIs) it refuses the second call with 482 (Cisco and Snom multiline phone for example) according with RFC 3261 section 8.2.2.2 because the two INVITEs have the same Call-Id, From tag and Cseq.
> If this behaviour is reasonable with a phone, it could not be acceptable for other types of client, first of all SIP-PSTN gateway.
> Is it correct this RFC interpretation? Maybe is this section inappropriate for gateways? 
> Is there something that I can do in the config file?
>
>
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