Hello List , Am working my way through the OnSIP getting started examples (4.0a) My testbed and network setup is similar to the OnSip example : 10.10.10.6 10.10.10.8 10.10.10.3 +-----------+ +-----------+ +-----------------+ | NATed UAs | | NAted UAs | |SER / MediaProxy | +-----------+ +-----------+ +------------------ | | | 5060 listened | | | | | | __________________________________________________ | PAT on Cisco 5060 passed through to 10.10.10.3:5060 ___|____ |router | |______ | | +-----------+ (--------) | NATed UA |-----(Internet) +-----------+ (--------) SER and Two UA's (SJphone) behind a Router with FW. SER and MediaProxy running on the same box (same internal LAN) Public IP address and Port (5060) passed through to Ser/Mediaproxy server via PAT on the Cisco router. (ie public_ip:5060=10.10.10.x:5060 where 10.10.10.x=ser/mediaproxy server address) UA's on internal LAN (10.10.10.x) can connect with Ser and make calls OK. UA from outside the LAN cannot register with SER. I've looked through most of the posts in July/August '05 but without luck Came across a similar type problem in a post with a response from Greger suggesting a patch to 'mediaproxy.py' and 'rtphandler.py' introducing a --vip option in mediaproxy.py I've tried this but without success. Maybe my patch is incorrect. I've also tried to follow Greger's advice for ser.cfg by announcing ; record_route_preset("public_ip") alias=public_ip This didn't seem to work. I've probably got something fundamentally wrong somewhere either in my patches or ser.cfg (?!) I'd be most grateful for any and all assistance to get me over this stage/hurdle. many thanks regards