[reSIProcate-users] Support sending REFER in a B2BUA scenario

["Cyril Raymond" <cyril@xxxxxxxxxxxxxxxxxxx>]

Hi,

   Am trying to write a B2BUA using DUM. I have the following scenario and need to support outgoing REFER messages.

 

-          Client A sends an INVITE to B2BUA (INVITE sip:abcd)

-          B2BUA responds with 100 TRYING

-          B2BUA sends outgoing INVITE to SERVER (INVITE sip:xxxx)

-          SERVER responds with 100 TRYING

-          SERVER responds with 200 OK

-          B2BUA sends ACK to SERVER for the 200 OK

-          B2BUA sends 200 OK to Client A

-          Client A sends ACK to B2BUA

SESSION with Client A is established.

 

-          Client B sends an INVITE to B2BUA (INVITE sip:abcd)

-          B2BUA responds with 100 TRYING

-          B2BUA sends outgoing INVITE to SERVER (INVITE sip:yyyy)

-          SERVER responds with 100 TRYING

-          SERVER responds with 200 OK

-          B2BUA sends ACK to SERVER for the 200 OK

-          B2BUA sends 200 OK to Client B

-          Client B sends ACK to B2BUA

SESSION with Client B is established.

 

Now I want Client A and Client B’s sessions to be merged, i.e., I require the B2BUA to send a REFER to Client A with the Refer-To header value as that of the SERVER (sip:yyyy).

This, I assume will prompt Client A to send an INVITE to sip:yyyy and thereby enable to interact with Client B.

 

My queries,

-          Is the above scenario valid? What happens to the initial session that got established for Client A. Should I send the REFER to Client A after sending it a BYE or should I send it as part of the same dialog and send a BYE after receiving a NOTIFY from Client A?

 

Any suggestion is greatly appreciated.

 

Thanks,

      Cyril