RE: Dynamic Directory & X.500

[Yoram Yaacovi <yoramy@MICROSOFT.com>]

(also forwarding to the new ldapext list where these discussions should take
place)

	> (Jyri) If we already have an email address directory based on
X.500 technology,
	> it would be convenient to attach the dynamic information for
NetMeeting
	>(and other online applications) to the existing entry
This is basically the idea behind the dynamic directories support in LDAP
V3. We want to support dynamic directories in 3 levels: the entry level, the
attribute level and the subtree (container, non-leaf object) level, in this
chronological order.

The ENTRY level: we added dynamic entries to LDAP. So now we have static and
dynamic entries, and a server implementation could possibly tie them
together through and OID attribute. This was the first and easiest to do and
the draft for that is in advanced stages, i.e. we agreed in the last IETF
meeting to go into last call. By the way, what prompted us to create the
dynamic entries approach, which is supported by ILS, was our need for such a
feature in NetMeeting. The are already several implementations of this
draft, like Lucent's and Microsoft's.

the ATTRIBUTE level: this is the approach you favor, and it is the ideal
approach in the long run. It is just harder to implement, since it means
that different attributes of the same object (entry), will probably have to
live in different storages: the dynamic attributes in a memory-based storage
and the static attributes in a disk-based storage, though this is really
implementation details. We already have a draft out for several months now
(<draft-ietf-asid-ldap-dynatt-01.txt>) to cover this aspect. I expect that
once the dynamic entries draft will get through we will start focusing on
this one.
The SUBTREE level: this level is the last to do and the farthest behind. I
was actually planning to solicit the list for interest in such a draft and I
have one half written. The reason for dynamic support for subtrees is
(beyond having a full, acroos the board dynamic directories support in LDAP)
is to allow containers with dynamic information: for example, a meeting can
be a container with dynamic information with dynamic participants. I the
X.500 tree, this can be represented as a dynamic subtree with the
participant being dynamic leaf objects. When the meeting object is gone
(expired), the participants "expire" as well. There are several models, and
I don't think I want to go into details here. The dynamic entries draft does
have some info on dynamic meetings, though.
	> (Gene) Our feeling is that if you try to update the static
	> directory based on dynamic entries, you will run
	> into limitations based on update rates (even without refresh
processing).  
I definitely agree with the above. The dynamic information will probably
always be stored separately from the static info to allow much faster and
more frequent updates.

Yoram
> ----------