Good luck thenā¦
If the traffic back to your phone is somehow blocked by one of the firewalls involved it canā¦
You obviously have no idea of how weird things can behave when routing or firewalling problems are involvedā¦
Have you ever null routed traffic back to an IP to temporarily block an hack attempt on one of your servers? I didā¦
While the communication with the system I was taking care of was established I was not letting my server talk back to the offending IPā¦
In essence, it looked like the server was not answering while it was actually trying to but not allowed to because of the null routeā¦
Have you ever seen an Internet security product block access between an HTTP server and its application server, I didā¦ The security company who conducted those tests was sure they had crashed our application server but I proved them otherwise because I established that only the link between the two servers was down, nothing else, and we tracked down the problem to the Internet security productā¦
That security company was sure they had crashed our app but their hack attempts had actually freaked out the Internet security product which began thinking the HTTP server was attacking the application serverā¦
Have you ever messed up (or had to fix messed up) subnet masks? Sometime one of the devices is able to talk to the other while the other is unable to because it doesnāt get routed to the right placeā¦
Have you ever put a server in a REAL DMZ (not a consumer router one) where you have to allow on a per port basis access to the outside, have to consider every possible fallback of the protocols involved (an example of that is DNS queries which switch from UDP to TCP sometimes (long answers, zone transfers, etcā¦)ā¦).
(A real DMZ actually puts more restrictions on outbound traffic than the LAN usually).
I did, even my home test server is setted up that wayā¦
The fact that you are not considering those kind of problems shows that you donāt have the necessary experience to question what we are saying because you would realize these are real possibilitiesā¦
Now as far as telephony knowledge is concerned I bow down to @tonyclewis which I doubt I will ever match in knowledge as far as this is concerned so I find your comment rather insulting to both him and meā¦
If this was a simple problem you would probably not have needed help so you have to consider weirder problemsā¦
As I said when I started this post, good luckā¦
This was my last post in this threadā¦
Nick
PS: You didnāt give enough information on your setup to figure out what is so different between your PC and those phonesā¦