Re: Compatibility requirements

[Harald Tveit Alvestrand <Harald@Alvestrand.no>]

At 11:02 23.01.00 -0800, Paul Hoffman / IMC wrote:
>At 02:31 PM 1/23/00 +0800, James Seng wrote:
>>Canonicalization algo is an ongoing process.
>
>Not for all character sets. It is fixed and done for Unicode, for example. 
>See Unicode Technical Report 15.

UTR 15 has a depressing number of references to the Unicode data files. And 
a depressingly low number of promises not to change those in incompatible ways.
One reason why UTR 15 hasn't met with universal acclaim from ISO, I think.

Still, much more work has been done on canonicalization of Unicode than any 
other reasonably large set I know of.


>>  Upgrades and changes to the algo
>>is unavoidable altho we can define some basic rules. Therefore, there will be
>>times when the algo is different on different client, say v1.0 and v3.0.
>
>Then those character sets can't be used unless we say that for any 
>particular character set, canonicalization must be done at all resolvers 
>and master zones (and caches...) using the exact same algorithm and that 
>when the algorithm changes everyone updates simultaneously.
>
>You can see the scalability and stability problem here.

I don't think it's that bad. But nearly.

                 Harald

--
Harald Tveit Alvestrand, EDB Maxware, Norway
Harald.Alvestrand@edb.maxware.no