Subject: Re: Unique identifiers for LDAP attributes

From: "Jim Sermersheim" <[email-masked]>
Date: Thu, 13 Jul 2000 11:12:59 -0600

>>> "David Chadwick" <[email-masked]> 7/13/00 11:02:47 AM >>>

>There is another interesting problem that you may be interested in 
>related to the non-use of OIDs. The matching rule used to select a 
>subschema definition is, wait for it....
>
> objectIdentifierFirstComponentMatch
>
>Thus the client needs to know the OID of the schema definition it 
>needs to selectively fetch it. But if LDAP never passes an OID to 
>the client, how does the client know which subschema definition it 
>needs? In order to solve this, it means we really need  a 
>"nonUniqueStringSecondComponentMatch" matching rule to be 
>defined for LDAP.

Though I agree with the general notion of moving toward the use of unique OIDs, there's a minor flaw with this statement.

objectIdentifierFirstComponentMatch uses the OID syntax which can either be a numericoid (1.2.3.4) or the descr form (cn), so it's still usable with short names as it stands today.

Jim

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From: "Kurt D. Zeilenga" <[email-masked]>
Date: Thu, 13 Jul 2000 10:37:33 -0700

>objectIdentifierFirstComponentMatch uses the OID syntax which can either be a numericoid (1.2.3.4) or the descr form (cn), so it's still usable with short names as it stands today.

But note a minor flaw in your statement.  A matchingRule should
evaluate to Undefined if the attribute value doesn't conform
to the defined attribute syntax.  With an OID in the attribute
value, the syntax is invalid, so the matchingRule is Undefined.

Kurt

---

From: "David Chadwick" <[email-masked]>
Date: Thu, 13 Jul 2000 20:31:19 +0100

Date sent:      	Thu, 13 Jul 2000 10:37:33 -0700
To:             	"Jim Sermersheim" <[email-masked]>
From:           	"Kurt D. Zeilenga" <[email-masked]>
Subject:        	Re: Unique identifiers for LDAP attributes
Copies to:      	<[email-masked]>, <[email-masked]>

> >Though I agree with the general notion of moving toward the use of
> >unique OIDs, there's a minor flaw with this statement.
> >
> >objectIdentifierFirstComponentMatch uses the OID syntax which can
> >either be a numericoid (1.2.3.4) or the descr form (cn), so it's
> >still usable with short names as it stands today.
> 

Now this could be the true meaning of the text that I said was 
particularly hard to understand in 8.4. At least I can understand 
what you have written and I agree with it

David

> Kurt

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David Chadwick
IS Institute, University of Salford, Salford M5 4WT
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