[HELP]: How to get Asterisk to forward SIP registration

Hi everyone,

I am currently working on a project which requires me to use Asterisk as an IP-PBX and have a seperate SIP Registrar. I was wondering as to how to set up the architecture for this. Here are my questions:

1- Is it possible for Asterisk to forward SIP registrations to the registrar? (not have Asterisk register, but the clients)
2- Can this be done using OpenSER as a registrar solution?

I may have misunderstood a number of things, but here is my brainstorming of possible setups so far (illustrating registration):
option A: Client <-> Asterisk <-> Registrar
option B: Client <-> Registrar <-> Asterisk
My only issue with option B is that it will have to route all calls to the Asterisk IP-PBX, and will have to be scaled as such, whereas in option A it can be scaled to a minimum.

Thanks in advance!

Sorry to bump this. Maybe the answer’s too obvious? Maybe my questions weren’t clear. Maybe I’m not writing this in the right forum. Please let me know…

Again thank you.