[Kamailio-Users] Path and received parameter

Klaus Darilion klaus.mailinglists at pernau.at
Tue Apr 7 12:26:25 CEST 2009



Iñaki Baz Castillo schrieb:
> 2009/4/7 Klaus Darilion <klaus.mailinglists at pernau.at>:
>> Hi!
>>
>> During REGISTER processing I call add_path_received() in the outbound proxy.
>>
>> Now if the INVITE is routed from main proxy to the client (via the OBP),
>> the OBP as to read the received parameter from the Ruote header and use
>> this value as destination URI. Is there a function available to perfomr
>> this action or do I have to do it manually (parsing Route header to the
>> get parameter)?
> 
> I don't remember now how exactly Path works, but AFAIR Path is only
> useful for registration. Later when the registrar receives an INVITE
> for that user, it extracts the Path from the location database and
> generates a Route with it:
> 
> 
> Alice              OBP              Proxy/Registrar                Bob
> 
> ----- REGISTER --->  ---- REGISTER + Path -->
> 
>                                                <----- INVITE --------
> <---- INVITE ------  <----- INVITE + Route --

                    ^^^^^^
Here at this point the OBP forwards the request to Alice based on the 
RURI. The RURI is the URI which Alice provided in the Contact header of 
the REGISTER. If Alice is behind NAT and sends the private IP address in 
the Contact header, then the OBP can not route the request to Alice.

Thus, there is the option to add the received parameter to the Path 
header. Then the OBP can derive the public IP:port from the received 
paramter in the Route header.

The question now is: Do I have to manually parse the route header, 
extract the received parameter and set $du, or is there somewhere a 
function which does this all?

regards
klaus



> 
> Am I wrong?
> 
> 




More information about the sr-users mailing list