[Serdev] SER as an extendable codebase/SIP stack - was: So who/what is SER for, anyway?

[Dragos Vingarzan]

Jan Janak wrote:
>   I do feel Dragos' pain with IMS-like scenarios implemented in SER as I
>   have been partially exposed to it, but I really think that a B2BUA
>   like application server would do a better job there.
>
>   
Maybe for an App Server. What I am trying to make out of it are the
signaling routing functions, which are all SIP proxies with different jobs:
- Proxy-CSCF - outbound proxy for UE, does NAT, security, asserts
identities, enforces transaction, dialog and network routing policies
- Interrogating-CSCF - almost stateless redirect proxy, just finds the
registrar for a given user identity, also does some security ops on
messages, like Topology Hidding
- Serving-CSCF - registrar and service trigger by filtering and proxying
traffic towards App Servers

To me it seemed SER territory.  There is no B2B in there, just some mild
UAC/UAS between the P and S-CSCF to synchronize those registrars. A
B2BUA would just kill the performance. Although this performance should
scale nicely, I wouldn't kill it with a bottleneck in this routing core.

So I hope I am not misusing SER here.

-Dragos