[sr-dev] very basic outbound support

[Juha Heinanen]

Juha Heinanen writes:

> how much of the above is currently supported?
> 
> - is registrar capable of overwriting the old contact uri and flow info
>   with new one if +sip.instance and reg-id values of an AoR match old one?
> 
> - is nat pinging turned off for outbound capable UAs?
> 
> - is request to an outbound capable us send over its flow rather than
>   based on contact uri?

i did some tests and looks like first feature is supported by k 4.0.

i was not able to test the second feature because i don't currently have
an ua behind nat available, but i suspect that it is not currently
supported and that nat pinging is based solely on usrloc nat_bflag.  in
theory is would, of course, be possible to test in config file if an ua
supports outbound and, if yes, leave nat_bflag unset.  however, such a
test is not very easy write, because it involves checking existence of
certain supported header and contact header params.  any ideas on this
one?

the third feature works for tcp and perhaps for udp too, but i was not
able to test the udp case.  that is, if contact uri host/port differs
from received ip/udp port, will received column be set or not.

-- juha