[OpenID] Negotiating a backup OP from the current OP

[Martin Atkins]

Drummond Reed wrote:
> This thread assumes a backup OP must be recommended from the current OP. But
> OpenID users and RPs already have a mechanism for "negotiating" selection of
> an OP:
> 
> a) The user lists all the OPs they use in their XRDS document (together with
> any special extensions/policies each OP supports, like PAPE)
> 
> b) The RP chooses the one that best satisfies it's own policies.
> 

In practice though, most people have their XRDS document hosted by their 
primary OP, so they can only publish what their OP will publish for them.