OpenSER or SER has a number of advantages in terms of SIP registration over Asterisk, these are: -
1. For a given peice of hardware, SER can support many more registrations than Asterisk, but Asterisk can manage quite a few anyway, so not as bigger advantage as you might hope.
2. SER can load balance by sending say 20% of calls to one asterisk server and the other 80% somewhere else.
3. SER when combined with say MediaProxy sorts out all sorts of far end NAT problems, which are often experienced with just Asterisk. This is probably the main reason why it would be desirable to come up with a working config to combine A2Billing and SER, so that end users can use SIP devices behind all sorts of NAT without having to reconfigure firewalls and routers.
One way forward is to create a SER configuration that uses the SIP buddies table in A2Billing to authenticate its users. So SIP endpoints are registered to SER, not Asterisk, but in terms of adding new users and general management of customers, this should all be done in A2B.
When a SER registered SIP user wishes to make a call, the call is passed through to Asterisk, and the user recognised by A2Billing on the basis of their SIP address. (caller ID maybe?)
A2Billing then handles the routing and charging of the call.
Given that the A2Billing Database can support many Asterisk servers, and SER can deliver calls to different Asterisk servers, this would make for a highly scalable system.
So if anyone has intimate knowledge of SER, unfortunately I do not, then your challenge, should you chose to accept it, is to: -
1. Install OpenSER
2. Combine MediaProxy module into the installation
3. Create a config that uses the A2Billing SIP buddies MySQL table for SER authentication.
4. Get it to pass through calls to Asterisk so that they are securely and automatically identified and authenticated by A2Billing.
and finally, tell us how you did it with sample configs and plenty of documentation, or get as far as you can, tell us where you get stuck and maybe with a bit of combined knowledge, we can make this config work.
Any offers? I'm sure many would be grateful, including me.
I have this setup only im using opensips.. and i couldn't get the media server too work.. and didnt configuire open sip...
Open sip load balance 4 a2billing
a2billing finds account routes too blue-box server (only because with a2billing cant assign multiple extensions to one account.... and no multi-tenet)http://www.cyfordcommunications.com