4 part domain names

Peter Risdon peter at circlesquared.com
Wed Nov 24 08:43:09 PST 2004


Dick Davies wrote:
> * Peter Risdon <peter at circlesquared.com> [1140 15:40]:
> 
>>Hexren wrote:
>>
>>>JM> On Wed, Nov 24, 2004 at 04:08:06PM +0100, Hexren wrote:
>>>JM> : location. 510 could identify a rack or a datacenter so that
>>>JM> : us.510.mail.example.com means "a mail server in the datecenter with
>>>JM> : the id 510 which serves the United States".
>>>
>>>JM> So 'us.510.mail' is an atomic, arbitrary identifier.  All three as a 
>>>unit
>>>JM> identify a certain node, and are selected purely for convenience of 
>>>human
>>>JM> operators, right?
>>>
>>>I would say yes.
>>>
>>>
>>>JM> I'm just making sure that the network doesn't treat 'us.510.mail' any
>>>JM> different than it would treat 'foobar', right?
>>>
>>>I would say yes too.
>>
>>
>>How does this square with the fact, as I understand it, that I can 
>>delegate authority for mail.example.com to new nameservers which can 
>>then publish host information about this zone?
> 
> 
> That's got nothing to do with the network.
> For example, I can create a host in example.com called
>  
> us.510.mail
> 
> and you can't stop me (evil laughter).

Hmmm... RFC921:

<quote>
  There are some limits on these names.
          They must start with a letter, end with a letter or digit and
          have only letters or digits or hyphen as interior characters.
          Case is not significant.

             For example:  USC-ISIF

       Hierarchical Names

          Because of the growth of the Internet, structured names (or
          domain style names) have been introduced.  Each element of the
          structured name will be a character string (with the same
          constraints that previously applied to the simple names).  The
          elements (or components) of the structured names are separated
          with periods, and the elements are written from the most
          specific on the left to the most general on the right.
</quote>

Peter.

-- 

the circle squared

network systems and software

http://www.circlesquared.com


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