Hello,
I have Micronet SP/5050s as a gateways to PSTN (connection to PSTN via PBX), SER as a proxy server and some voip phones. Next picture shows my topology:
_________ _______ _________ _____ |SIP Phone|___| SER |____|SP 5050/S|____|PBX1 |____ PSTN |_________| |_______| | |____1____| |_____| | | . . . | _________ _____ |__|SP 5050/S|____|PBXn |____ PSTN |____n____| |_____| (in other location)
If voip user calls some number, his UA sends INVITE message (to SER) with Request-uri=To-uri=number1@domena.sk.
My SER overwrite Reguest-uri to number2@ip_address_of_micronet an sends this INVITE message to Micronet. INVITE includes Reguest-uri which is different from To-uri. I need dial number2 in PBX.
Note: Number1 may contain prefix - it tell which PBX use. SER must prepare real PSTN number - number2 and send INVITE message to corect gateway.
My problem is that micronet gateway dials numbers from To-uri field, not from Request-uri field of INVITE message. So it dials number1. All numbers managed by SER are not available.
I can overwrite called number (number1 from To-uri) in micronet gateway too - gateway uses prefixes, but only 10 - it is few for me. And I need more micronet gateways with different prefixes (I have more PBX each in other place) - micronet's prefixes decentralize number logic from one SER to more gateways.
I was trying to overwrite To-uri field of phone's INVITE message in SER, but if SER sends other message with overwrite To-uri (200 OK, ACK, reply from micronet) to phone, phone rejects it - message has wrong To-uri field.
When I has Cisco 2600 as a PSTN gateway - it dialed numbers from Reguest-uri field, but Cisco is more expensive.
Do you know some solution for me or other gateway, which can I use - gateway must dial numbers from Reguest-uri field and its price is circa 300$ (PSTN gateway with 6 FXO ports).
Thank you,
Regards, Laco