Re: RFC 2596 questions

[hahnt@us.ibm.com]

Greetings,

The discussion on this list regarding attribute descriptions has been quite useful to me - thanks for continuing it.  I also hope that 2251 bis is much better about spelling out how these are to be handled.

From the discussions so far on this list, it appears that attribute descriptions might be used in various ways.  The trouble with this is that it implies that there is no "generic method" for handling attribute descriptions since each one might imply some special code in the server you are contacting.  Unlike controls and extended operations, there is nothing in the rootDSE that gives any indication as to what attribute descriptions are supported or not.  Thus, the use of them will, at least for the moment, result in applications that don't work, in general, across different server implementations.

Should we investigate some additional rootDSE attribute to indicate the set of attribute descriptions that are supported?  Further, when a new attribute description is defined, should we be assigning OIDs and keeping these as an additional part of the subschemasubentry data?

I know of the following attribute descriptions that have been discussed:

;binary
;lang-<some code>

from the discussions on the list and the I-Ds and RFCs that have been published we have a sense of what each means.  Are there other attribute descriptions now proposed/defined?

One more observation:  there is currently a thread on the mailing list regarding "crosstalk issues" between multiple controls specified on LDAP operations.  It seems that we run the same risk with multiple attribute descriptions if we are not careful.

I think that the discussions over the past day have clarified alot of the intended handling of at least ;binary and ;land-<some code>.  Thanks!

I hope that we get the same level of detail into 2251 bis and the definition of future attribute descriptions.

Regards,
Tim Hahn

Internet: hahnt@us.ibm.com
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