Guaranteeing the Integrity of Bindings

Another in the series of messages about advanced collection design team
proposals:

Jim Amsden in his comments on the advanced collections spec said that he
believes it is never possible to guarantee the integrity of bindings that
cross servers.  So requiring servers to guarantee the integrity of any
binding that they allow to be created will have the result that no one will
ever implement cross-server bindings.

The kind of case he had in mind (I think) was one where the server where the
resource resides becomes inaccessible to the server where bindings resides.
So at least while the 2 servers are out of touch, the binding will be
broken.

We think that it is not impossible to guarantee integrity of bindings even
in cases like this, if the server is willing to take enough trouble.  It can
store a copy of the target resource locally, and insure that no changes are
allowed except when both servers are accessible.

We agree that it is unlikely that cross-server bindings will be supported
because of the difficulty of guaranteeing integrity, but we do want to
insist the servers fail BIND requests where they can't guarantee integrity
of the binding.  (We are planning to remove all normative language about
cross-server bindings, but just keep the generic statement that integrity of
bindings has to be guaranteed.)

If you don't care so much about integrity, and do want cross-server
referencing, then redirect references are the better tool to use.


--Judy

Judith A. Slein
Xerox Corporation
jslein@crt.xerox.com
(716)422-5169
800 Phillips Road 105/50C
Webster, NY 14580

Received on Wednesday, 15 September 1999 14:09:19 UTC