Port used for SIMPLE (SIP)

[Mark Doliner]

On Thu, 17 May 2007 17:51:16 -0400, Dale Worley wrote
> On Thu, 2007-05-17 at 15:57 -0400, Ethan Blanton wrote:
> > Dale Worley spake unto us the following wisdom:
> > > Does the SIMPLE code ask the kernel for a dynamically assigned port, or
> > > does it try to use 5060?  The former strategy is infinitely preferred,
> > > since Pidgin has no way of knowing whether 5060 is reserved (on this
> > > system) for another application.
> > 
> > It appears to use a dynamically assigned port between 5060 and 5160.
> > If someone else already has 5060, it will use 5061, ... 5159.
> > 
> > Are you experiencing trouble, or was this idle curiosity?
> 
> It turned out that my instance of Pidgin was using 5070, which was
> needed by the SIP PBX I was trying to test-run on the same host.
> 
> Given that Pidgin is a SIP client and can register with any port 
> that it feels like with no effect on the user, it really should 
> leave the choice of port up to the kernel (which presumably knows 
> the local policy).

Hmm, I'm not sure I agree.  It's often convenient for user's to know what
ports are used by a given protocol so that they can set their home
router/firewall device to foward those ports to their computer ("DMZ"). 
Although I guess upnp makes this less of an issue.  And we don't really
publish this information anywhere... but maybe we should.

Is there any reason your SIP PBX needs to run on port 5070?  Pidgin tries to
use a port between 5060 and 5160... couldn't your SIP PBX do the same thing?

-Mark