Dear Concern,
Good day. I am working on voip field more then six years. I have my own VOIP service company www.voip-traffic.com. I have voipswitch server, VOS3000 server and Asterisk with freepbx server also have some Mobile Dialer and Softphone.
Please go through my profile here, I did same project. I will be happy to assist you.
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Thanks and Regards
Mr. Zahid Khan