RE: Feature discovery (Was: RFC 2596 questions)

["Steven Legg" <steven.legg@adacel.com.au>]

Tim,

> -----Original Message-----
> From: hahnt@us.ibm.com [mailto:hahnt@us.ibm.com]
> Sent: Saturday, 16 September 2000 21:59
> To: ietf-ldapext@netscape.com
> Subject: Re: Feature discovery (Was: RFC 2596 questions)
>
>
>
> Hi all,
>
> I like the idea of extending the schema information with the set of
attribute descriptions that are known to the server.
>
> Both approaches described so far:
>
> 1) extend the attributeTypes value to allow for additional fields to be
specified within each value, add a new value that defines the OIDs used in
the field
> 2) add a new attribute to the subschemasubentry and contain all the
information here
>
> are in the right direction.
>
> Approach 1) has the benefit that just by looking at the attributeType
value,
> you can get an indication if any attribute descriptions might have been
used
> in creating/modifying entries that contain this attribute.  However, there
> would be the issue of whether or not the server supported the additional
> data in the attributeTypes value.
>
> Approach 2) doesn't change the attributeType value definition (nice for
> upward compatibility).  On the downside, though, in order to see what
> attribute description a given attribute type can have attached to it, a
> not-so-easy-search of the new schema attribute would have to be performed.
>
> After writing up this short discussion of the approaches, I think I prefer
> Approach 1) where the "DESCRIPTORS ( <OID> "$" ... )" clause of the
> attributeTypes value is an optional piece in the format of the value.
>
> Is there agreement here?

No, unless you can convince the X.500 committee to also extend the
definition of the syntax of the attributeTypes operational attribute.
If further fields are added to the LDAP string encoding of values of
the attributeTypes attribute then it will be out of sync with its X.500
ASN.1 syntax definition and BER encoding. That will be painful for
those of us with servers supporting both LDAP and X.500. The ldapSyntaxes
attribute is fair game though.

Regards,
Steven

>
> Regards,
> Tim Hahn
>
> Internet: hahnt@us.ibm.com
> Internal: Timothy Hahn/Endicott/IBM@IBMUS or IBMUSM00(HAHNT)
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