[asterisk-dev] Issue with PJSIP contacts being "unavailable"

[asterisk at phreaknet.org]

On 6/27/2023 6:07 PM, Joshua C. Colp wrote:
>
> I'm not sure what exactly you are referring to with "using the 
> transport used for registration". If "rewrite_contact" is set to yes 
> then the existing active connection should get used. If you are 
> referring to Asterisk establishing a new outgoing connection to the 
> registered Contact, then as long as it is optional and doesn't break 
> other behavior fine.

Basically, suppose a device registers on a port, associated with some 
configured transport.

The reason I'm doing this now is that initially, calls out *to* devices 
would just use the default transport (the first one configured, or 
something like that). Specifying a transport= in the endpoint explicitly 
ensured they'd only use the appropriate one. The problem still remains 
though that we don't necessarily know what transport a device is going 
to use in advance, and it could also change at any time.

  I don't know if this would be a "new" outgoing connection to the 
contact or not... I was noticing this issue with outbound calls to 
devices using the wrong transport (e.g. an ATA registered using TLS, and 
Asterisk would call the device using UDP, on a different port). The 
description for "rewrite_contact" says "Allow Contact header to be 
rewritten with the source IP address-port" which doesn't really clarify 
that, but if that means it'll always use the same transport out to the 
device that the device initiated a connection on, no matter what, then I 
think that will do the trick. I just want Asterisk to go along with 
whatever the device wants to do. If there's a gap with "rewrite_contact" 
then I guess a new option is still needed to do the other half.