Hi, maybe this question is a bit off-topic so I'm sorry for that.
My question is about SIP providers using OpenSer that associate PSTN numbers to their local clients (SIP accounts):
Usually the client must register to OpenSer in order to receive calls. Then it will appear in location table with "Contact=sip:clientX@IP". Suppose clientX has two PSTN numbers associated in a ENUM entry: +34999000111 +34999000222
When anyone in PSTN world calls to +34999000222 the call will arrive to the OpenSer from a gateway in an INVITE like:
INVITE sip:+34999000222@gateway SIP/2.0 To: sip:+34999000222@gateway
The OpenSer will do the lookup in location table and finally send this INVITE to the clientX:
INVITE sip:clientX@IP_clientX SIP/2.0 To: sip:+34999000222@gateway
The info about the called PSTN number is just available in "To" header, so a way to get different behaviour for each associated PSTN number is matching "To" URI. Is common to do it? which other alternatives are there?
Thanks for any comment. Regards.