[SR-Users] ACK not sent and rr-enforced

[Dominguez Jover, Ricardo]

Hi again,

I'm still working in this issue. I've noticed that iptel proxy is writing in the ACK message the following:

ACK sip:username at myproxyIP:5060;.....   -> ACK is not sent to the client. tcheck_trans fails. If a force the transfer -> t_relay do nothing

while sip2sip and VoIP-Talk are writing:

ACK sip:username at userprivateIP:5060;....  -> ACK is sent to the client

In both cases, contact URI sent in the 200 OK message by my proxy is the private IP address of the client  sending the 200 OK, so I don't know why IPtel doesn't use it in the ACK. I find a lot of information about lost ACKs in posts, but not this particular issue.

Could anyone give me some related information that can help me to solve this issue?

Best regards,

Ricardo Dominguez




De: sr-users-bounces at lists.sip-router.org [mailto:sr-users-bounces at lists.sip-router.org] En nombre de Dominguez Jover, Ricardo
Enviado el: lunes, 07 de marzo de 2011 20:03
Para: sr-users at lists.sip-router.org
Asunto: [SR-Users] ACK not sent and rr-enforced

Hi everybody.

I am using Kamailio 3.1 and RTP proxy for internet calls. I'm using external test accounts to check if the calls are established and the media flow is ok.

When I use a sip2sip.info or  VoIP Talk accounts, then all is working fine between my internal and these external accounts.

But when I use a iptel.org account and this account calls to an internal account (registered with kamailio), then callee sends the 200 OK to the SIP proxy and the SIP proxy to iptel. IPtel.org proxy sends the ACK to my proxy with this lines at the end of the packet:

P-hint:  rr-enforced\r\n
P-hint:  rr-enforced\r\n

And my SIP proxy never resends the ACK to the callee, so the callee resends OK 200 periodically and after 32 seconds sends a BYE message and the call is finished.

I've been reading posts about missing ACKs but I can't find the answer to my problem, that it seems like "t_check_trans" doesn´t recognize the ACK as related to a transaction. But this is only with IPTEL accounts, my proxy SIP is working with other SIP providers, so I don't know if forcing relay of every ACK packet is a good idea.

Any help would be appreciated.

Thanks,

Ricardo