- From: Koen Holtman <koen@win.tue.nl>
- Date: Tue, 13 Aug 1996 00:57:23 +0200 (MET DST)
- To: "David W. Morris" <dwm@shell.portal.com>
- Cc: dsr@w3.org, http-wg%cuckoo.hpl.hp.com@hplb.hpl.hp.com
David W. Morris: > >The difficulty I believe is in the codification of features in a way that >will satisfy everybody (or mostbodies). This is a very general problem. Quoting from the Montreal minutes: Harald Alvestrand pointed out that the group does not have a unified model; we have a desire to create a language to describe what the user wants and a language to describe what the server has and we don't have a unified model for bringing those together; until that model comes together--neither is going forward. As far as I know, the only complete specification of such unified languages is in the transparent content negotiation draft. One of these languages (Accept headers including Accept-Features) could be used for user agent profiles. I'm always wondering if (transparent) content negotiation can't be made simpler, and the idea of using the power of indirection to simplify the negotiation process is exciting. But sadly I can't see a way to use this power to simplify the whole thing (yet). [....] >Finally there are a whole bunch of characteristics which describe an >individual installation of a browser product which I believe Koen has >already noted should fit well under content negotiation. Yes, I see this as the main problem with UA profiles: they cannot contain _all_ preferences and capabilities (which include things like having viewers for unusual MIME types, the quality factors of the MIME types, and the quality factors of the accepted languages), because if they would contain everything, you would basically get a different profile file for each user (except maybe on the LANs of boring companies), and the whole profile caching scheme breaks down horribly. And if UA profiles can't cover all preferences and capabilities, then you still need a second negotiation mechanism to handle the things not in the profile. So UA profiles won't solve all of our problems. They could at best be a short-term stopgap measure to reduce the pain before we have a general mechanism. But we already have a complete draft spec for a general mechanism, transparent content negotiation, which will do much more than negotiate on UA features alone. The general mechanism could be finished well before the stopgap! I estimate that to go from here to a complete internet draft for profile sharing would take months at least. The addition of a third party in the negotiation process generates so many security/reliability/authentication/privacy problems that the fast production of a simple draft seems out of the question. >Dave Morris Koen.
Received on Monday, 12 August 1996 16:00:46 UTC