[OpenID] OP initiated and RP to RP flows

[Andrew Tomlinson]

There seems to be some talk about OP initiated and RP to RP flows, but I am
not sure if/how OpenID can do it. Can someone more enlightened than me
comment on this please?

For "OP initiated" my searches only found
http://connectid.blogspot.com/2007/05/openid-op-first.html and reading the
OpenID 2.0 spec there is 10.1. "... Relying Parties SHOULD accept and verify
assertions about Identifiers for which they have not requested
authentication" and 13. "Discovering OpenID Relying Parties" which look
promising...

I couldn't find any mention of RP to RP flow (or RP1->OP->RP2). Is this
possible with OpenID 2.0? There are plenty of interesting uses for this
especially with "user not present" scenarios.

I guess both of these are well out of scope. Can anyone confirm?

Thanks,

Andrew