Just what *is* a hostname (rfc952/1123, etc)

[David Carmean]

On Wed, Jan 23, 2002 at 03:44:43PM +0000, Barry Margolin wrote:

> David Carmean  <dlc-bu at halibut.com> wrote:

[snip]

> >So far I haven't been able to figure out from the RFCs whether a 
> >hostname is just the leftmost label in a domain name, or whether 
> >the *entire* domain name (fully-qualified or relative) must be 
> >considered subject to the RFC952/1123 restrictions?
> 
> What difference does it make?  IIRC, the rules about hostnames apply to
> each label, not the fully-qualified name.

It seems to be perfectly legal to create a domain named "foo_b#r&.com.", 
if I'm reading RFC2181 correctly; the question is whether the name of 
any node in the entire subtree below that zone cut can be a legal 
Internet hostname.

The practical matter is that I'm writing some tools and I want to 
get my t's crossed and my i's dotted [0] correctly, so-to-speak.


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