[sr-dev] Status of outbound

[Peter Dunkley]

>> One of the things that was requested at the start of the outbound work
>> in
>> Kamailio was the ability to "force" outbound even when a UA does not
>> support it and to be able to use the outbound flow tokens for NAT
>> traversal instead of contact aliasing on "single server"
>> configurations.
>
> fine IF there is some advantage in putting the information in rr header
> instead of contact header.
>

The argument that was presented was that putting the information in the rr
header is more aligned with published standards.

I have come across a number of devices at interconnects that incorrectly
strip parameters that they do not recognise from the Contact-URI.  While
this is clearly incorrect behaviour on their part getting operators and
vendors to fix their equipment is not always possible.

As I said, I do not have a need for this myself as I plan to use separate
edge proxies and registrars - but I can see where the requirement came
from.

>> To my mind this means we need to double-RR when there is just a single
>> proxy/registrar in use.  It also means that, when there is a single
>> proxy/registrar and the Path extension would not normally be used, we
>> still need to do something to get the flow tokens (userinfo part of the
>> Path-URI) into the location table so that they can be used for NAT
>> traversal.
>
> sounds much more complicated than contact aliasing.
>

Indeed.  But I can see where it is sometimes needed.

Peter

-- 
Peter Dunkley
Technical Director
Crocodile RCS Ltd