[asterisk-dev] Asterisk and "305 Use Proxy"

[Johansson Olle E]

14 sep 2006 kl. 13.07 skrev Wolfgang Hottgenroth:

> Hi,
>
>
> I'm wondering how to configure asterisk the right way to handle  
> "305 Use
> Proxy" correctly or whether there is a bug in asterisk in the 305  
> handling.
Well, it's not a bug, but indeed a missing feature. I haven't seen  
any equipment
out there using it or any bug report asking for support of it.

>
> I've asterisk sitting as registrar and rtp-proxy and so on in front of
> two opensers. These both opensers redirect INVITEs as soon as their  
> load
> is beyond a configure limit to each other. And they increase the  
> port to
> use for every redirect.
>
> So, the first INVITE goes to openser 1 on port 5060, which  
> redirects to
> openser 2 and requests port 5061 to be used in the Contact header (cp.
> RFC 3261, #21.3.4). When this proxy in turn redirects, it requests  
> port
> 5062.
>
> When asterisk receives the first redirect, it repeats the INVITE
> perfectly using the new URI from the Contact header out of the 305
> response. When it then receives the second redirect, now with port  
> 5062
> in the Contact header, it repeat the INVITE again, using the address
> from the Contact header, but not using the port from the Contact  
> header,
> instead it uses the default port 5060.
>
>
> Does anyone have a hint for my to configure asterisk to handle this
> situation RFC conform?
>
Well, it surprises me that we do anything intelligent with that reply.
No, there's no support for this in the SIP channel. I would like to see
a SIP trace of this from Asterisk's point of view to estimate what can
be done.

We have some, although poor, support for 302 redirect, no support
for multiple choices or use proxy.

/O

---
Olle E. Johansson * Asterisk Evangelist, developer * VOOP A/S
olle at voop.com