Re: A Comment on 9. [1] of the requirements document.

[George Belotsky <george@register.com>]

Please note 2.3.3.  You are specifically told to avoid storing
labels as 7-bit ASCII.


2.3.1. Preferred name syntax

The DNS specifications attempt to be as general as possible in the rules
for constructing domain names.  The idea is that the name of any
existing object can be expressed as a domain name with minimal changes.

...........

2.3.3. Character Case

For all parts of the DNS that are part of the official protocol, all
comparisons between character strings (e.g., labels, domain names, etc.)
are done in a case-insensitive manner.  At present, this rule is in
force throughout the domain system without exception.  However, future
additions beyond current usage may need to use the full binary octet
capabilities in names, so attempts to store domain names in 7-bit ASCII
or use of special bytes to terminate labels, etc., should be avoided.





On Fri, Apr 13, 2001 at 01:04:31PM -0400, Hollenbeck, Scott wrote:
> >-----Original Message-----
> >From: George Belotsky [mailto:george@register.com]
> >Sent: Friday, April 13, 2001 12:43 PM
> >To: ietf-provreg@cafax.se
> >Subject: A Comment on 9. [1] of the requirements document.
> >
> >
> >Section 9. [1] is quoted below.
> >
> >
> >"  [RFC1035] restricts the encoding of Internet host and domain names
> >   in the DNS to a subset of the 7-bit US-ASCII character set.  More
> >   recent standards, such as [RFC2130] and [RFC2277], describe the need
> >   to develop protocols for an international Internet.  These and other
> >   standards MUST be considered during the protocol design process to
> >   ensure world-wide usability of a generic registry registrar protocol."
> >
> >This is not quite correct.  Quote from RFC1035 follows.
> >
> >"Although labels can contain any 8 bit values in octets that make up a
> >label, it is strongly recommended that labels follow the preferred
> >syntax described elsewhere in this memo, which is compatible with
> >existing host naming conventions.  Name servers and resolvers must
> >compare labels in a case-insensitive manner (i.e., A=a), assuming ASCII
> >with zero parity.  Non-alphabetic codes must match exactly."
> >
> >Thus, DNS labels can contain arbitrary octets.  If such labels are
> >properly supported by existing software, it may be possible to make
> >use this functionality.
> 
> The statement is absolutely correct.  Please re-read section 2.3.1,
> "Preferred name syntax", starting at the bottom of page 6.  It very clearly
> constrains the label space for domain and host names as described.
> 
> <Scott/>

-- 
-----------------------------
George Belotsky
Senior Software Architect
Register.com, inc.
george@register.com
212-798-9127 (phone)
212-798-9876 (fax)