[OpenID] is openid 2.0 a lightweight identity system?

[Robert Yates]

On 2/9/07, Jonathan Daugherty <cygnus at janrain.com> wrote:
>
> I don't know what you mean by "full XRDS support."  For the purposes
> of OpenID, "XRDS support" and "Yadis support" are equivalent.
>

Some things that have confused me for instance.

The Yadis specification states "A Relying Party Agent MAY ignore all
elements in an XRD element other than the Service elements." is that
true when a RP MUST perform XRI Resolution?

It also states "If a Yadis XRDS includes more than one XRD element,
the Yadis Resource Descriptor is the last XRD element. A Relying Party
Agent MAY ignore other XRD elements." Again is this true for an XRDS
document retrieved via xri-resolution.

The point is I don't know and there is a significant learning curve
for me before I can answer these questions and if I am implementing an
RP I need to know.

I guess I'll rephrase my question a little, at the moment it appears
that to implement an openid 2.0 RP I need to read and understand the
contents of both the xri-resolution specification and the xri spec, a
total of 107 pages.

I think the use cases you previously outlined can be achieved with
slight tweaks to Openid 1.1 and Yadis (a much more digestible spec
that I can understand without understanding xri-resolution). So what
value does the xri-resolution and xri dependencies add to openid 2.0,
apart from support for i-names?

Could i-names support be moved to an extension?  As an RP implementor
I would certainly prefer it.

I apologize for all the questions, am just trying to understand. I
seem to have a LOT of reading to do if I want to build an RP and with
previous versions it didn't seem such a herculean task.

Rob

p.s. someone mentioned that i-names support is optional, is this true?