Main goal of this project minimize the BW / or packet size of G729 and G723 codec in sip mode .
Freeware billing any
1. Build a asterisk and vpn server
2. Server to client asterisk are connected via internet using the vpn .
3. Server will received the call in sip mode in g729 and g723 . convert the g729 into ilbc codec . and g723 to less frame 5.3 kbps
4. Server asterisk connected to client asterisk via openvpn . client asterisk and gsm gateways are connected via local ip address
5. Server asterisk send the call to client asterisk using the openvpn . then client asterisk convert the call originating codec .so gsm gateways detect the call cause, [ gsm gateways have only 2 codec one g729 and g7231
1. Gateways add/remove/edit
2. tariff add/remove/edit
3. client add/remove/edit
4. dialing plan add/remove/edit
5. codec conversation
6. other necessary
Billing part we need very few things in billing [ like we need only one client part in billing that is gateway client .
You have to make step by step document. Give me live teaching . we will arrange you all dedicated sever and client .
Active interested and experienced person mail me .
GMT + 6