Re: [radext] Alissa Cooper's Discuss on draft-ietf-radext-ip-port-radius-ext-11: (with DISCUSS and COMMENT)

["David B. Nelson" <[e-mail]>]

Lionel wrote:

> My understanding is that, when defining authorization type attributes that
> are use over RADIUS, it is not deemed required to define the specific use of
> these attributes nor the error handling.

Yes and no.  While attributes can be re-used in multiple applications and use cases, the *semantics* of the authorization needs to be unambiguous.  Remember, RADIUS doesn't have the notion of applications, so the meaning of attributes needs to be idempotent, if good interoperability to to be achieved.

> As for other AAA documents, this draft is not specifying a specific procedure
> or a new protocol application. It is just about defining attributes that can
> be used in the use case described in this document but also in any other
> solution that would see advantage to reuse these attributes. 

Yes, but see above.

> The main point of this document is to ensure that the definitions of these
> attributes are correct (type, length, value), unambiguous and describe in
> which messages they can appear.

The definition of RADIUS attributes also includes their semantics, not just their syntax.

> The exact behavior of the client/server using these attributes is often left
> out of this kind of document. It is up to the specification describing the
> implementation the clients and/or servers using these attributes to define
> this error handling.

I disagree.  Leaving out semantics and client/server behavior is not traditional for RADIUS and is likely to lead to poor interoperability.

Regards,

Dave Nelson