From owner-freebsd-questions@FreeBSD.ORG Wed Nov 24 16:43:09 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3B88516A4CF for ; Wed, 24 Nov 2004 16:43:09 +0000 (GMT) Received: from lorna.circlesquared.com (host217-45-219-85.in-addr.btopenworld.com [217.45.219.85]) by mx1.FreeBSD.org (Postfix) with ESMTP id 71B3A43D46 for ; Wed, 24 Nov 2004 16:43:08 +0000 (GMT) (envelope-from peter@circlesquared.com) Received: from [127.0.0.1] (localhost.circlesquared.com [127.0.0.1]) iAOGgpmW067123; Wed, 24 Nov 2004 16:43:02 GMT (envelope-from peter@circlesquared.com) Message-ID: <41A4BA0B.80501@circlesquared.com> Date: Wed, 24 Nov 2004 16:42:51 +0000 From: Peter Risdon User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.7.3) Gecko/20041124 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Dick Davies References: <20041123233501.GA82229@dogma.freebsd-uk.eu.org> <5557305861.20041124004849@hexren.net> <20041124000014.GA83249@dogma.freebsd-uk.eu.org> <8763344284.20041124022927@hexren.net> <20041124141737.GA11648@dogma.freebsd-uk.eu.org> <5315017844.20041124160806@hexren.net> <20041124152355.GD11648@dogma.freebsd-uk.eu.org> <10516350570.20041124163019@hexren.net> <41A4AAEF.6080202@circlesquared.com> <20041124163324.GJ12945@lb.tenfour> In-Reply-To: <20041124163324.GJ12945@lb.tenfour> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit cc: FreeBSD Questions Subject: Re: 4 part domain names X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 24 Nov 2004 16:43:09 -0000 Dick Davies wrote: > * Peter Risdon [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: 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. Peter. -- the circle squared network systems and software http://www.circlesquared.com