I have decided to post this hopefully helpful guide to people on Menatelecom who are having problems with VoIP.
A short intro to the problem I was having (and if it relates to your). I’m currently subscribed to one of the home packages from Menatelecom. They provide you with a WiMAX modem that is also a router, and routers, due to NAT, end up hiding the devices behind your network from the Internet. This causes some problems with applications that require ports to be opened. For the sake of keeping my mother and the wallet happy, I decided to install a VoIP ATA (Linksys SPA3102) which she uses to make and receive calls internationally. The ATA uses SIP. On Batelco or any other ISP which do not provide a VoIP service you are fine, just open ports and you’re good to go. On Menatelecom’s home packages however, you notice that the router has a couple of telephone RJ11 ports. And guess how they provide such service? Yep, SIP. As a result you will have a conflict with your ATA (using SIP’s port 5060) and Menatelecom’s (also using port 5060). One way to test this is simple, visit http://canyouseeme.org/ and enter 5060 in the box. It is probably the only port open.
The solution proposed here depends on your device (Menatelecom’s) and your VSP (VoIP Service Provider). You must be able to open ports on your WiMAX router (this is how to access the admin section if you have one of the Motorola models), Port Forwarding > Forwarding and set the ports you require. And your VSP supports SIP over an alternative, non-default port. If you use the default port (5060) in your ATA you would notice your device gets registered but is unable to make calls (SIP messages get sent, but never received, probably going to the router’s SIP client first and getting discarded).
I knew using an alternative port would work, but for some reason it didn’t. I actually thought the SPA was acting up and possibly broken since even firmware updates did not “fix” the problem. The issue was that changing the port setting in the ATA was not enough I had to modify the VSP’s URL to include the alternative port like so: server.vsp.com:1234 (note: using port 1234 as an example!). If you have a SPA3102 here are the modified fields in the Voice > Line 1 tab (you may or may not need the OB proxy, VSP dependent):
If your VSP does not support alternative ports, I suggest you use a service such as Voxalot which provides many cool features such as: adding multiple VSP, setting smart dial plans (routing calls to different VSPs depending on patterns), voicemail AND of course, using a different SIP port.
Hopefully this post gives some ideas on how to fix your VoIP SIP problems with Menatelecom (maybe even other providers around the world that use similar routers). If you require assistance do not hesitate to comment below or send me an email.