I am able to call from private ip to real ip under SIP server using SIP extension. but unable to call from Real IP to private IP using the same setting. When I call from Real IP to Private IP the square box pops up and the call timer starts counting till around 8 seconds. But I cannot hear or see during this time. After 8 or so seconds it says connection was not established due to firewall or network. Error message attached. When I use real IP in both places it works perfectly. Is it mandatory to use Real IP for M100? if not please tell me the solution. We are planning to buy a minimum of 64 licenses of M100 the answer is very crucial for us.
You can call from a private ip to public ip . it must work without any issue .
But you cant call from a LAN ip to public ip , or you cant call LAN ip to LAN ip without proper NAT. Really is working like a mobile phone number . So if you want some one to reach you of course you need to have public ip. And in NAT the public ip can change any time as per ISP.
Thanks for your reply. In my scenario both the computers using M100 are connected to Internet (the private ip through NAT, the real ip directly). The NATing is working properly as the private ip is getting Internet without any problem. Although the private IP is under NAT it is still connected to a SIP server and registered properly. The realip is also registered under the same SIP server. I am calling from one SIP extension 1014 to 1011. When I call from the extension 1014 (the one in private ip) to 1011(the one in realip) it works properly. But when I call from 1011 to 1014 it fails. Since both of them are connected to a SIP server logically 1011 should be able to call 1014. When I call from 1011 to 1014 I get the incoming call popup square box(proving that the real ip could reach the private ip under NAT) and the call timer starts counting till about 8 seconds and after that I get the error message that I had attached. During this 8 seconds I cannot hear the audio or see the video.