Re: [homegate] HOMENET working group proposal

Fernando Gont <> Thu, 30 June 2011 02:18 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id 2354411E80B7; Wed, 29 Jun 2011 19:18:53 -0700 (PDT)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -0.845
X-Spam-Status: No, score=-0.845 tagged_above=-999 required=5 tests=[BAYES_00=-2.599, FRT_BELOW2=2.154, J_CHICKENPOX_13=0.6, RCVD_IN_DNSWL_LOW=-1]
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id th8yixeSksiw; Wed, 29 Jun 2011 19:18:52 -0700 (PDT)
Received: from ( []) by (Postfix) with ESMTP id AC26211E8072; Wed, 29 Jun 2011 19:18:48 -0700 (PDT)
Received: by ywp31 with SMTP id 31so914432ywp.31 for <multiple recipients>; Wed, 29 Jun 2011 19:18:48 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; bh=5R1kl567g64jluzP6JJoCOuLzwQdjltc/wElb7GRDE4=; b=OD5+MOcAE4Kb3XF4NjSp7e5fvgRQ4T5MhIXYsUF2Aghxe21tLFF0FCp+GgXKAg6Ovv AnSG2nxKQA9XF4q4Ri5dbcH3T1qfcwkz8FtB7/waFlWtfhmw16/sj0rmM1dxovSmYH1o W9FVI57zNALTx9rvaeTHmjyRNO2iWFNwqnxjc=
Received: by with SMTP id d20mr1391642ago.19.1309400328019; Wed, 29 Jun 2011 19:18:48 -0700 (PDT)
Received: from [] ([]) by with ESMTPS id y15sm1579479ann.44.2011. (version=SSLv3 cipher=OTHER); Wed, 29 Jun 2011 19:18:46 -0700 (PDT)
Sender: Fernando Gont <>
Message-ID: <>
Date: Wed, 29 Jun 2011 23:18:27 -0300
From: Fernando Gont <>
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv: Gecko/20110516 Thunderbird/3.1.10
MIME-Version: 1.0
To: Jari Arkko <>
References: <>
In-Reply-To: <>
X-Enigmail-Version: 1.1.2
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 7bit
X-Mailman-Approved-At: Wed, 29 Jun 2011 20:39:36 -0700
Cc: "" <>, IETF Discussion <>
Subject: Re: [homegate] HOMENET working group proposal
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Broadband Home Gateway Discussion <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Thu, 30 Jun 2011 02:18:53 -0000

Hi, Jari,

My high level comment/question is: the proposed charter seems to stress
that IPv6 is the driver behind this potential wg effort... however, I
think that this deserves more discussion -- it's not clear to me why/how
typical IPv6 home networks would be much different from their IPv4

Bellow you'll find some comments/questions about the proposed charter.
They are not an argument against or in favour of the creation of the
aforementioned wg, but rather comments and/or requests for clarification...

On 06/29/2011 05:47 AM, Jari Arkko wrote:
> o Service providers are deploying IPv6, and support for IPv6 is
> increasingly available in home gateway devices. While IPv6 resembles
> IPv4 in many ways, it changes address allocation principles and allows
> direct IP addressability and routing to devices in the home from the
> Internet. This is a promising area in IPv6 that has proved challenging
> in IPv4 with the proliferation of NAT.

NAT devices involve two related but different issues:
* address translation
* an implicit "allow only return traffic" firewall-like functionality

One would hope/expect that the former will be gone with IPv6. However, I
don't think the latter will. As a result, even when you could "address"
nodes that belong to the "home network", you probably won't be able to
get your packets to them, unless those nodes initiated the communication

For instance (and of the top of my head), this functionality is even
proposed in the "simple security" requirements that had been produced by

> o End-to-end communication is both an opportunity and a concern as it
> enables new applications but also exposes nodes in the internal
> networks to receipt of unwanted traffic from the Internet. Firewalls
> that restrict incoming connections may be used to prevent exposure,
> however, this reduces the efficacy of end-to-end connectivity that
> IPv6 has the potential to restore.

I personally consider this property of "end-to-end connectivity" as
"gone". -- among other reasons, because it would require a change of
mindset. I'm more of the idea that people will replicate the
architecture of their IPv4 networks with IPv6, in which end-systems are
not reachable from the public Internet.

Fernando Gont
e-mail: ||
PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1