Length of labels (RE: [idn] IURL vs URL, IDNS name vs DNS name)

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

At 19:00 11.02.00 +0200, Jonathan Rosenne wrote:

>The UCS could be encoded using A-Z 0-9. On average each non-ASCII character
>would require 3 to 4 characters. All we need to change is to allow longer
>names in DNS and to provide a viewer which decodes these creatures back to
>UCS or the local code page.

Unfortunately the limit of 63 octets per domain name component is enshrined 
in a 6-bit length field in RFC 1035, section 4.1.4 (the 2 upper bits are 
used as a flag to indicate pointers or "something-elses"), so "all we need 
to change" to get this length increased is every single piece of DNS 
software on the planet.

Not that we might not come to that anyway...

                          Harald

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