[sr-dev] How to contruct ACK/BYE correctly in dialog with NATed client

[Min Wang]

Hi

My issue is how to construct ACK correctly in the dialog in case of
NATed  client.  ( please see
http://lists.sip-router.org/pipermail/sr-dev/2010-February/006145.html
for the scenario detail )


nated-u1(bob)---> P1 --> nated-u2 (alice)


e.g:  bob calls alcie,

(A) In the normal case,

     U1 ---> P1 ---> U2
           Invite->
     <--200 OK
	     ACK -->	

The good ACK msg capted from P1 to U2 is:
#
U 67.154.255.47:4060 (P1) -> 67.154.250.3:2051 ( public ip/port for U2)
ACK sip:alice at 172.16.8.42:2051;line=e96ci3a9 SIP/2.0.


(B) In the abormal case,

     U1 ---> P1 ---> U2
           Invite->
     	     ACK -->	
	     BYE -->
        <--488

P1 check something and need to send ACK/BYE to u2

The pseudo code try to use dialog module function: 

     dialog.request_inside(&method_ACK,&reqbuf,NULL, d,cb,cbp)