Re: [Kamailio-Users] add_path_received and OBP problems

Florian Meister schrieb: Depends .... For SIP NAT traversal. Almost all SIP clients are symmetric (send/receive SIP on the same port) - thus by always use the "received" information instead of the provided "Contact" you should not have negative impacts. Exception: IIRC, I once saw Cisco SIP phones behind a Cisco PIX which were asymmetric (can't remember if it was SIP or RTP). Also, applying NAT traversal in all cases, does not allows 3rd party registrations (which are usually not needed). Regarding RTP NAT traversal. By activating the media relay for all calls you have: - you need more bandwith - you may need more RTP proxies (high call volume) - you might add more delay (this is probably a problem if the relay is in e.g. Europe and caller/callee are in US. If at least on of the parties is "near" the RTP proxy the additional delay should me negligible) + less customers will ask for help due to NAT problems (e.g. NAT detection does not work, stupid SIP clients ...) + some countries require lawful intercept, which must not be noticeable by the costumer. As the LI requires a media relay (to record audio) you do not have a choice and have to activate the media relay for all calls anyway. regards klaus