Re: Named Referrals Questions.

[Christopher Lukas <lukas@cs.wisc.edu>]

Leonid Dubinsky wrote:
> QUESTION 1.
> 
> The draft seems to imply that objects with a 'ref' attribute can have
> subordinate objects with a 'ref' attribute. This can be used to make
> subordinate referrals more specific. Mark Smith confirms that this is
> the idea. I think this should be more explicit in the text.
> 
> QUESTION 2.
> 
> The draft seems to also imply that objects with a 'ref' attribute can
> have "normal" subordinate objects held by the same server. This can be
> used to make superior referrals smart, i.e. to keep superior referrals
> for each naming context held by the server in an object superior to that
> naming context.
> 
> For example, if a server holds two naming contexts:
> 
>         ou=abc, o=xyz, c=us and
>         dc=subd, dc=acme, dc=com
> 
> it can hold objects with the following dns that contain a 'ref'
> attribute with the superior reference:
> 
>         o=xyz, c=us
>         dc=com.
> 
> Such "smart" superior references can be used to provide referrals more
> specific (and meaningful) than the default superior reference held in
> the root DSE.

I think both of these are not specifically allowed, but seem like _one_
way to do "smart" superior references. I think the reason we didn't
specifically describe this as a way to do smart superior references is
that it is not the only way to do them. Section 6 says:

If the LDAP server's root DSE does not contain a ref attribute, the
server may return one or more references that the server determines via
a method not defined in this document to be appropriate.

By this we meant to allow some kind of smart superior references not
necessarily based on ref entries. I was actually thinking of some kind
of DN-based index which would have the same functionality as your idea.
I like your idea becuase it seems natural, but I can't help but feel
that there might be some other way someone would want to be smart about
superior references hence leaving this open seems like a good idea. Of
course, off-hand, I can't think of any other ways, but I feel like there
are. Any thoughts on this?


>WHEN DOES THE SERVER RETURN "NO SUCH OBJECT" RESULT IN THE PRESENCE OF
>REFERENCES?
>
>I think that the answer should be: "when an object requested is not held
>by the server but: 1) is subordinate to a non-reference object held by
>the server, and 2) there are no reference objects held by the server
>located between this non-reference object and the requested object." 
>(This sounds more evolved than it looks on a picture (on as part of a
>name resolution algorithm)).

This seems like a reasonable thing to put in the draft. I think it's
implied by the document which is, of course, obivous to the authors, but
perhaps not obvious to everyone else.

Sorry it took a while to get on this, but work on these things tends to
be fitful.

- Chris

------------------------
Christopher E. Lukas
Internet Scout Project 
http://scout.cs.wisc.edu