Re: future of identifiers

Phillip Hallam-Baker <> Wed, 06 November 2013 01:38 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id 9ED4521F9DA0 for <>; Tue, 5 Nov 2013 17:38:13 -0800 (PST)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -2.488
X-Spam-Status: No, score=-2.488 tagged_above=-999 required=5 tests=[AWL=0.111, BAYES_00=-2.599, HTML_MESSAGE=0.001, NO_RELAYS=-0.001]
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id 7UsQG1Gv13Mm for <>; Tue, 5 Nov 2013 17:38:13 -0800 (PST)
Received: from ( [IPv6:2a00:1450:4010:c04::234]) by (Postfix) with ESMTP id 85DF911E81B2 for <>; Tue, 5 Nov 2013 17:36:34 -0800 (PST)
Received: by with SMTP id y6so7157356lbh.39 for <>; Tue, 05 Nov 2013 17:36:33 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=Y7EiSjG0zLchMiWxMQb0yyg4DsQJI65UEYhxOm9CVo4=; b=MksBTa9zlax5gKi/uC1aIAE+6SCG3Uoyy3eiQ4k+eshwtEh6KQq2KKo4nIlTXCnTsT XmJ6HqMMk1wh+VPjCG5KYsxfPjjLwSfIbG1B3jtwcxFjVgbNn63reAMn9KngPrxsCHrF UhoPjY5mlI8DcWEcijaiUK1sjEzVkIiUHdX6OWVJo4rNTU2qJgCV/4DTISumJYTyg01Y vydUDP9aj0iQLj5amLrwd4MDyUtBDNdvG5+0x2cYfPiTALZl+x6QwAy36h0EI8odXV+C FEeKn2mKMKVAku3NpPFU6M5WWSV/jYFY9XJvdPKdrxcqoztIkaP9rRvEfFw1Pm6EUODi reDA==
MIME-Version: 1.0
X-Received: by with SMTP id p10mr335792lag.21.1383701793495; Tue, 05 Nov 2013 17:36:33 -0800 (PST)
Received: by with HTTP; Tue, 5 Nov 2013 17:36:33 -0800 (PST)
In-Reply-To: <>
References: <> <> <> <>
Date: Tue, 05 Nov 2013 20:36:33 -0500
Message-ID: <>
Subject: Re: future of identifiers
From: Phillip Hallam-Baker <>
To: Jari Arkko <>
Content-Type: multipart/alternative; boundary="089e0158c9f8e0613304ea782df3"
Cc: " Discussion" <>
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: IETF-Discussion <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Wed, 06 Nov 2013 01:38:13 -0000

Another set of concerns is raised by the question of whether an identifier
be human readable or not or have implicit semantics.

The reason the DNS is such a hotbed of political intrigue is that there are
names like and there is an expectation that resolving such
identifiers maps to the companies that have been using the names as

Then there is the question of whether the identifier space is open or
closed. There are only 65535 valid IP ports and so assignment or well known
ports has different considerations to assignment of SRV tags which fulfill
the same function.

IP addresses are also identifiers and there are different considerations
for the different parts of the address. An IPv6 address must be globally
unique and the upper 64 bits have to map to some form of routing
information that is unique at a network level.

But another way to look at an IPv6 address is that it is a 64 bit address
and a 96 bit port space.