Re: [Tsvwg] WGLC for Port Randomization starts now (April 1st)

Joe Touch <touch@ISI.EDU> Thu, 07 May 2009 23:34 UTC

Return-Path: <touch@ISI.EDU>
X-Original-To: tsvwg@core3.amsl.com
Delivered-To: tsvwg@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id D7C353A6A0E for <tsvwg@core3.amsl.com>; Thu, 7 May 2009 16:34:02 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.599
X-Spam-Level:
X-Spam-Status: No, score=-2.599 tagged_above=-999 required=5 tests=[AWL=0.000, BAYES_00=-2.599]
Received: from mail.ietf.org ([64.170.98.32]) by localhost (core3.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OuWQHn5lQz87 for <tsvwg@core3.amsl.com>; Thu, 7 May 2009 16:34:02 -0700 (PDT)
Received: from vapor.isi.edu (vapor.isi.edu [128.9.64.64]) by core3.amsl.com (Postfix) with ESMTP id 107B83A67FD for <tsvwg@ietf.org>; Thu, 7 May 2009 16:34:02 -0700 (PDT)
Received: from [75.217.216.156] (156.sub-75-217-216.myvzw.com [75.217.216.156]) by vapor.isi.edu (8.13.8/8.13.8) with ESMTP id n47NZD9B004405; Thu, 7 May 2009 16:35:15 -0700 (PDT)
Message-ID: <4A037030.6040107@isi.edu>
Date: Thu, 07 May 2009 16:35:12 -0700
From: Joe Touch <touch@ISI.EDU>
User-Agent: Thunderbird 2.0.0.21 (Windows/20090302)
MIME-Version: 1.0
To: mallman@icir.org
References: <20090415033307.F00C0CD585E@lawyers.icir.org>
In-Reply-To: <20090415033307.F00C0CD585E@lawyers.icir.org>
X-Enigmail-Version: 0.95.7
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 7bit
X-ISI-4-43-8-MailScanner: Found to be clean
X-MailScanner-From: touch@isi.edu
Cc: "James M. Polk" <jmpolk@cisco.com>, tsvwg <tsvwg@ietf.org>
Subject: Re: [Tsvwg] WGLC for Port Randomization starts now (April 1st)
X-BeenThere: tsvwg@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: Transport Area Working Group <tsvwg.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/tsvwg>, <mailto:tsvwg-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/tsvwg>
List-Post: <mailto:tsvwg@ietf.org>
List-Help: <mailto:tsvwg-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/tsvwg>, <mailto:tsvwg-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 07 May 2009 23:34:02 -0000

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Some comments on Mark's comments...

Mark Allman wrote:
>> This is the start of the WGLC for Port Randomization, which will
>> last for 14 days - starting April 1st, going through April
>> 15th. Please review this document and post comments to the TSVWG
>> list and authors.
> 
> I read the document today.  Comments:
> 
...
>   - Section 2.1: There is a claim that the ephemeral port space is
>     "traditionally" from 49152-65535.  I think it is more traditional
>     for hosts to use monotonically increasing ports starting at 1024.
>     Even if hosts do use this upper range they also use this lower range
>     a bunch.  I'd nuke this statement as probably wrong, but at least
>     dubious.

"traditionally" is incorrect; it's *defined* as that range by IANA.

Source ports can use any port they want, though - as Mark points out -
they tend to avoid the "system" ports.

>   - In 2.3 you might note that an alternative approach is for both hosts
>     to keep state about recent connections.  I am not arguing it is a
>     good approach or a bad approach...just an alternate approach that
>     would work towards minimizing the collision rate.

And, FWIW, some of that state is already being kept, e.g., in TIME-WAIT
on the side that initiates connection close. It's only for connections
on the other side that keeping such state is even needed.

Joe
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAkoDcDAACgkQE5f5cImnZrsHYQCdHojYyD53iVk2o+ZORHzUuzJR
QVcAnjNWQWH2Rh0On3jCTD5SPXoCrKUo
=VxEn
-----END PGP SIGNATURE-----