I am located in Toronto and running asterisk server in Toronto
for some reason none of my user from Pakistan are able to connect to my server from Pakistan.People from US .Kuwait,Saudia Arabia are able to connect.
My Server is Running Asterisk 1.6 running on 5060 port
At least Dubai blocks SIP. I don’t know about Pakistan, but they could also block SIP.
Solution - VPN and SIP over VPN or you can try using IAX - some voip phones could use IAX.
We did vpn over ssh using instructions like provided here: tldp.org/HOWTO/ppp-ssh/
And over that vpn we did communication between 2 asterisks, and to each of them there were SIP phones connected.
Some SIP phones have vpn clients. You should do only server part on US side, and if you use such phones - then it will be easier.
Or - you will need special server in Pakistan to make vpn.
Be aware - in Dubai this was prohibited by law (we did our sip over vpn in other country).
Thanks Adeel will definitly contact you but for now I screwed up my server as soon as it is fixed I will contact you,
btw I am located in Markham where abouts you are