<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: times new roman,new york,times,serif; font-size: 12pt; color: #000000'><div><div>Hi,<br><br></div>I'm trying out the b2b module on opensips and have encountered an issue regarding PRACK.<br><br></div><div>In
particular I have a scenario where the called number replies with a 183
session progress (Require: 100rel and RSeq: 1) and then a few seconds
later with a 180 Ringing (Require: 100rel and RSeq: 2).<br><br></div><div>What
happens is that opensips correctly replies with a PRACK to the 183
response but then doesn't do the same when it receives the 180
provisional response.<br><br></div><div>Excerpts from the logs show this happening when the 183 message is received:<br><br>Aug 9 17:31:14 [2528] DBG:b2b_entities:b2b_tm_cback: Found require hdr<br>Aug 9 17:31:14 [2528] DBG:b2b_entities:b2b_tm_cback: Found 100rel header<br>Aug 9 17:31:14 [2528] DBG:b2b_entities:b2b_send_req: start type=1<br><br></div><div>but when the 180 response arrives, there are no similar entries.<br><br>It is my understanding that from a SIP signalling point of view the b2b module should reply with a PRACK to the 180 response too or am I missing something ?<br><br></div><div>Any ideas as to why this may be happening or could it be a bug ?<br><br></div><div>Many thanks,<br></div>Giuseppe<br></div></body></html>