[OpenSER-Users] OpenSER SIP registrar - third party registration

[Pascal Maugeri]

Hi

I would like to make OpenSER SIP REGISTRAR to advertise my SIP server
that a user just registered successfully to the domain. My server has
to make a call to this user as soon as he's registered.

First of all is this called "third party registration" ?

In practice how does it work ? OpenSER sends a REGISTER to my server
and my server replies with 200 OK ? Which script command should I use
?

Thanks in advance for your help
Pascal