- From: Geoffrey M. Clemm <geoffrey.clemm@rational.com>
- Date: Wed, 3 Jan 2001 09:03:38 -0500 (EST)
- To: ietf-dav-versioning@w3.org
- CC: ckaler@microsoft.com, yarongo@crossgrain.com
OK, it looks like this is worth one more thread during last call. As Tim pointed out, several members of the working group strongly support MUST NOT, so let's look closely at the tradeoffs for saying MUST NOT vs. SHOULD NOT. I believe that recent threads on this topic have sufficiently motivated why it is valuable for a client to be able to count on version URL's not being re-used. Certainly a client certainly doesn't lose anything because of this requirement. So it is reasonable to conclude that those arguing for "SHOULD NOT" are server implementors who feel that it is too costly for them to satisfy this requirement. In earlier threads, the response has been that a server writer can just tack on a GUID to the version URL to guarantee it isn't re-used (RFC-2518 describes a variety of mechanisms for cheaply creating GUID's). Perhaps those in favor of SHOULD NOT (Chris? Mark?) could explain to the group why this would be a problem? Note that several of the techniques described in 2518, don't "guarantee" uniqueness, but rather make it extremely unlikely that there will be a collision ... I believe that "extremely unlikely" is sufficient for satisfying the "MUST NOT". Cheers, Geoff From: Tim_Ellison@uk.ibm.com This is too bad ... I strongly support "MUST" -- for all the reasons that you have heard already from numerous members of the working group. "Mark A. Hale" <mark.hale@interwoven.com> on 2001-01-02 08:59:01 PM I strongly support the use of SHOULD in this case. Thanks for making the change. > I talked with Chris on the phone today, and he asked for a > change and a clarification > > - change the MUST to a SHOULD for the "version URL can never be re-used". > > Chris is concerned that various reasonable ways of getting version URL > uniqueness have a chance of collision if a given host name is mapped > to a new server. > > In general, I try to avoid SHOULD in favor of MUST whenever possible. > Since there has been a lot of debate on this issue, I suppose I can > live with SHOULD here.
Received on Wednesday, 3 January 2001 09:04:34 UTC