Re: [Softwires] draft-ietf-softwire-lw4over6 excluding Well Known Ports

Cong Liu <gnocuil@gmail.com> Tue, 03 June 2014 10:24 UTC

Return-Path: <gnocuil@gmail.com>
X-Original-To: softwires@ietfa.amsl.com
Delivered-To: softwires@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 8B07B1A01A8 for <softwires@ietfa.amsl.com>; Tue, 3 Jun 2014 03:24:17 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.999
X-Spam-Level:
X-Spam-Status: No, score=-1.999 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, SPF_PASS=-0.001] autolearn=ham
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id DS3UcK10cuAV for <softwires@ietfa.amsl.com>; Tue, 3 Jun 2014 03:24:15 -0700 (PDT)
Received: from mail-qg0-x235.google.com (mail-qg0-x235.google.com [IPv6:2607:f8b0:400d:c04::235]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id EBFC81A018A for <softwires@ietf.org>; Tue, 3 Jun 2014 03:24:14 -0700 (PDT)
Received: by mail-qg0-f53.google.com with SMTP id f51so12883601qge.12 for <softwires@ietf.org>; Tue, 03 Jun 2014 03:24:08 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; bh=O+/dktJDeJoM7+pW930WJNPnFvo/Bnhez1jqrtI+pOg=; b=PjP7V0KGHeywXr8cIFFSv97T02YyWePNx4oMYgxoOJZqpAPcb00dZDzmZmhqHJluIP Ff4j61Iw+eFpX2O4ogw50l+YueSpEppiYQ/Xu7E8JTI1vRegeAsETWFsHtmp/zCx7YC3 gEUtnH3hebP4+yLh7gBfQvY99HBMZXBAH+yQlWB5ZOGN8MvmUYW/bgeKbzOwMJCqTauY pwjfoiZB0yn15E2nJIDIFol/MgTfqb9LtFGt3O2mywaW/fbtvjFO0XohW6sZO1wvd1hO 29YXBWheaOh+gw0aFv7MIAZoo0LoJg0B5o1edEQV3hDlBvOgJceGem94yKoEz55wOc3T 8Mzg==
X-Received: by 10.140.49.76 with SMTP id p70mr54121296qga.86.1401791048828; Tue, 03 Jun 2014 03:24:08 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.96.149.2 with HTTP; Tue, 3 Jun 2014 03:23:48 -0700 (PDT)
In-Reply-To: <CAFFjW4jAFMe3Zc4FcfXB8CHdHMzns71dP86hRJ7jPiqT738+eg@mail.gmail.com>
References: <53422B8F.2020109@ericsson.com> <37A243DD-5249-4070-AB19-6DFFCFE17AA7@gmx.com> <DC98AF70-DBF1-48AD-8699-2FC4E645FF40@cisco.com> <C3B32B71-79EE-408F-A92C-D40021DC9A5A@gmx.com> <92E51E75-2914-421F-B222-7478EC3D6A02@cisco.com> <BBFBDEAA-0D2B-4A74-86E4-88824712EA26@gmx.com> <CAFFjW4igsiqS5yNUECerMzpZSkmPaL28sqef1usZdxt87y1jEw@mail.gmail.com> <538CB982.2060502@gmail.com> <CAFFjW4jxY=fjCszomzHyWhYtb+1QE+bN-afp_Qi5_32WxUydJg@mail.gmail.com> <538CD547.8070108@gmail.com> <CAFFjW4hqGQ0-oxTcgtFeWgbZRBj5d+82YWJT5Dfh763PORZCYw@mail.gmail.com> <CEE0FE7C-9204-494D-8229-E055E57FAF85@cisco.com> <CAFFjW4gE2byQ7YYZMQfZ3YksmjF2pGYYMp6=A+G1HhY8WHmqTg@mail.gmail.com> <D1054450-6A7E-4EF8-A3D2-D535C60E70DA@cisco.com> <CAFFjW4jAFMe3Zc4FcfXB8CHdHMzns71dP86hRJ7jPiqT738+eg@mail.gmail.com>
From: Cong Liu <gnocuil@gmail.com>
Date: Tue, 03 Jun 2014 18:23:48 +0800
Message-ID: <CAF+sHxHSOHXrrPQDYp7PzNkEDQG_yfE5gmLsRXZPYNX8gxbSGw@mail.gmail.com>
To: Wojciech Dec <wdec.ietf@gmail.com>
Content-Type: multipart/alternative; boundary="001a11370a3483ceb604faebe929"
Archived-At: http://mailarchive.ietf.org/arch/msg/softwires/um0Ae4NIG4GZqxDt9cj7BLNY8rY
Cc: draft-ietf-softwire-lw4over6@tools.ietf.org, Ole Troan <ot@cisco.com>, Yong Cui <cuiyong@tsinghua.edu.cn>, Softwires WG <softwires@ietf.org>
Subject: Re: [Softwires] draft-ietf-softwire-lw4over6 excluding Well Known Ports
X-BeenThere: softwires@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: softwires wg discussion list <softwires.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/softwires>, <mailto:softwires-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/softwires/>
List-Post: <mailto:softwires@ietf.org>
List-Help: <mailto:softwires-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/softwires>, <mailto:softwires-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 03 Jun 2014 10:24:17 -0000

Hi Woj,

Assume a=0 and PSID-len=5, then the ports are divided into [0,2047],
[2048,4095], ...
Just drop the first piece, and allocate others to clients. That's how a=0
works.

a=6 can also work, but I don't think it's a SHOULD for a=6 to solve the WKP
issue.

Best Regards,
Cong


2014-06-03 18:01 GMT+08:00 Wojciech Dec <wdec.ietf@gmail.com>:

> Thanks. I'm not sure I get your example though. To exclude ports 0-1023,
> the excluded port "subnet" would be 0x0000/6. Which would be equivalent to
> a=6...
>
>
>
>
>
> On 3 June 2014 11:31, Ole Troan <ot@cisco.com> wrote:
>
>> Wojciech,
>>
>> > Could you show a working example of that in action, along with the set
>> of PSIDs containing the usable port ranges?
>>
>> in LW46, ports are provisioned per client. so, I don't understand what
>> you want a working example of. that's just like assigning 192.168.0.10 -
>> 192.168.0.255 in a DHCP pool. in the PSID case you will not assign ports
>> 0000/10
>>
>> cheers,
>> Ole
>>
>>
>> >
>> > Cheers
>> >
>> >
>> >
>> >
>> > On 3 June 2014 10:51, Ole Troan <ot@cisco.com> wrote:
>> > Woj,
>> >
>> > in the LW46 case, you can still do a=0, and ensure that you don't
>> provision any PSID which results in the well known ports.
>> >
>> > cheers,
>> > Ole
>> >
>> > >
>> > > On 2 June 2014 21:49, Tom Taylor <tom.taylor.stds@gmail.com> wrote:
>> > > There's a difference between setting a=6 and setting aside the lowest
>> PSIDs because they occupy that port space. The value of a determines how
>> ports are assigned to each PSID, but does not affect the usable PSID
>> numbering space.
>> > >
>> > > I think that you should illustrate how you think this would work
>> before we reach a conclusion.
>> > > A setting of a=6 arrives precisely at what the goal is here, exclude
>> ports 0-1024. So if there is a need to have another way of achieving that,
>> by creating some excluded magic PSID value that corresponds to 0-1024, we
>> would like to know why is that relevant and how it is supposed to work in a
>> system where the PSID conveys to the CE the port-range.
>> > >
>> > > Regards.
>> > >
>> > >
>> > > RECOMMENDED is part of the RFC 2119 boilerplate. The
>> (unintentionally) missing term is NOT RECOMMENDED.
>> > >
>> > > Tom
>> > >
>> > >
>> > > On 02/06/2014 3:27 PM, Wojciech Dec wrote:
>> > > Well, I'm referring to the "RECOMMENDED" part. If the recommendation
>> is NOT
>> > > to allocate ports 0-1024, then this effectively recommends that
>> a-bits=6.
>> > > Moreover the meaning of SHOULD vs RECOMMEND should be questioned. The
>> > > latter is not a regular normative term, and arguably if the
>> recommendation
>> > > is for excluding 0-1024 then a=6 looks like the SHOULD. If anyone
>> wants the
>> > > full port set, then a=0 would be an obvious consequence.
>> > >
>> > >
>> > > On 2 June 2014 19:50, Tom Taylor <tom.taylor.stds@gmail.com> wrote:
>> > >
>> > > Not sure how you read that, but it can be fixed by putting a comma
>> after
>> > > "SHOULD be 0" and replacing "to allocate" with "thus allocating".
>> > >
>> > > Tom
>> > >
>> > >
>> > > On 02/06/2014 12:14 PM, Wojciech Dec wrote:
>> > >
>> > > Uhm, this appears to mean that the RECOMMENDED a-bits SHOULD be 6.
>> > >
>> > >
>> > > On 26 May 2014 13:24, Ian Farrer <ianfarrer@gmx.com> wrote:
>> > >
>> > >   Hi,
>> > >
>> > > This one slipped my mind….
>> > >
>> > >   From a discussion with Ole during the MAP dhcp last call, there was
>> a
>> > > discussion about the exclusion of provisioning WKPs to CPEs -
>> > > http://www.ietf.org/mail-archive/web/softwires/current/msg06010.html
>> > >
>> > > In previous versions, the lw4o6 used to reference
>> > > sun-dhc-port-set-option,
>> > > which also stated that the WKPs should not be assigned. This advice
>> got
>> > > lost when changing to reference map-dhcp for PSID format.
>> > >
>> > > Here’s a wording change proposal to resolve this:
>> > >
>> > > Section 5.1
>> > >
>> > > Original text (last sentence, para 7):
>> > >
>> > > "For lw4o6, the  number of a-bits SHOULD be 0."
>> > >
>> > > Proposed change:
>> > >
>> > > "For lw4o6, the number of a-bits SHOULD be 0 to allocate a single
>> > > contiguous port set to each lwB4.
>> > >
>> > > Unless a lwB4 is being allocated a full IPv4 address, it is
>> RECOMMENDED
>> > > that PSIDs containing the well-known ports (0-1023) are not allocated
>> to
>> > > lwB4s.”
>> > >
>> > > Please let me know if you are OK with the proposed change.
>> > >
>> > > cheers,
>> > > Ian
>> > >
>> > >
>> > >   Good spot on the WKP exclusion. Before the lw4o6 draft was updated
>> to
>> > >
>> > > reference map-dhcp for configuration,  the port configuration was
>> > > described
>> > > in sun-dhc-port-set-option, which also stated that the WKPs should
>> not be
>> > > assigned. This advice got lost when changing to reference map-dhcp.
>> I’ll
>> > > make a suggested text update for the lw4o6 draft to fix this. Does
>> that
>> > > work for you?
>> > >
>> > >
>> > > yes, that would be good.
>> > >
>> > > cheers,
>> > > Ole
>> > >
>> > >
>> > > _______________________________________________
>> > > Softwires mailing list
>> > > Softwires@ietf.org
>> > > https://www.ietf.org/mailman/listinfo/softwires
>> > >
>> > >
>> > >
>> > >
>> > > _______________________________________________
>> > > Softwires mailing list
>> > > Softwires@ietf.org
>> > > https://www.ietf.org/mailman/listinfo/softwires
>> > >
>> > >
>> > >
>> > >
>> >
>> >
>>
>>
>
> _______________________________________________
> Softwires mailing list
> Softwires@ietf.org
> https://www.ietf.org/mailman/listinfo/softwires
>
>