Re: LCUP issue: trigger mechanism or not?
"Jim Sermersheim" <[email protected]> Wed, 04 Sep 2002 21:25:25 -0600
| Newsgroups | gmane.ietf.ldup |
|---|---|
| Message-ID | <[email protected]> |
>>> Mark C Smith <[email protected]> 09/04/02 01:20PM >>> >Jim Sermersheim wrote: > > >> The draft states that it "is intended to allow LDAP clients to >> synchronize with the content stored by LDAP servers". but also states >> that it wants to solve the problem of triggered actions (Section 3, >> Bullet 3). > >I agree that triggered actions should be within LCUP's scope. The LCUP >authors have tried to balance the server implementation burden with the >client implementation burden. In particular, I would really like to >avoid creating an LCUP protocol that requires a server to store >client-specific state (that just won't scale when their are thousands or >hundreds of thousands of clients). > > >> Most of the rest of the draft is consistent with the notion of >> synchronization, but tends to downplay support for triggered responses. >> Do we want this to be a useful event driver, or is the idea that we just >> preserve the easy stuff of what prior drafts could do? >> >> Specifically, the left-out items in Sections 5.1, 5.2, and 5.3 deter >> from the effectiveness of the "persist" mode. >> >> Current users of Persistent Search rely on the notion of change types. >> Section 5.2 assumes that change types are used for partial replication, >> and thus discounts them as useful for LCUP. I don't think this is >> valid. > >Are you saying that LCUP should support clients that only want to store > a subset of the entries that are targetted by the LCUP search they >issue? No, even worse. I'm saying there are clients that wish to store nothing. They only want to be triggered when a certain action occurs. >Even if you do want to support that, I don't see the problem. The >LCUP model (as defined today) is that it is up to the client to >determine whether a change is interesting or not. The assumption is that >clients will store UUIDs for each entry they are interested in, and that >the client can compare stored data with the new entry data to determine >what has changed. That does not seem like an excessive burden to me. For a client that stores nothing, and makes no comparisons today with psearch, the extra burden is huge. >A related comment: perhaps section 5 should be moved to an appendix that >is named "Features Left Out of LCUP." It is not core to LCUP, but is >useful to provide historical context and rationale for why some things >are not included in LCUP. > >-Mark Smith > Netscape Jim