[PWE3] Re: comments on draft-ietf-pwe3-hdlc-ppp-encap-mpls-05.txt
Luca Martini <lmartini@cisco.com> Tue, 16 August 2005 17:47 UTC
Received: from localhost.localdomain ([127.0.0.1] helo=megatron.ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1E55XU-0003aO-VZ; Tue, 16 Aug 2005 13:47:52 -0400
Received: from odin.ietf.org ([132.151.1.176] helo=ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1E55XS-0003aG-NF for pwe3@megatron.ietf.org; Tue, 16 Aug 2005 13:47:50 -0400
Received: from ietf-mx.ietf.org (ietf-mx [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id NAA25373 for <pwe3@ietf.org>; Tue, 16 Aug 2005 13:47:49 -0400 (EDT)
Received: from rtp-iport-1.cisco.com ([64.102.122.148]) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1E566n-0007yY-Hd for pwe3@ietf.org; Tue, 16 Aug 2005 14:24:24 -0400
Received: from rtp-core-1.cisco.com (64.102.124.12) by rtp-iport-1.cisco.com with ESMTP; 16 Aug 2005 10:47:39 -0700
X-BrightmailFiltered: true
X-Brightmail-Tracker: AAAAAA==
X-IronPort-AV: i="3.96,113,1122879600"; d="scan'208"; a="6155045:sNHT22929604"
Received: from [209.245.27.1] ([10.32.241.115]) by rtp-core-1.cisco.com (8.12.10/8.12.6) with SMTP id j7GHlYT6028264; Tue, 16 Aug 2005 13:47:36 -0400 (EDT)
Message-ID: <430226B5.5060700@cisco.com>
Date: Tue, 16 Aug 2005 11:47:33 -0600
From: Luca Martini <lmartini@cisco.com>
User-Agent: Mail/News Client 1.0+ (X11/20050603)
MIME-Version: 1.0
To: Stewart Bryant <stbryant@cisco.com>
References: <42CEABCE.8020303@cisco.com>
In-Reply-To: <42CEABCE.8020303@cisco.com>
Content-Type: text/plain; charset="us-ascii"; format="flowed"
Content-Transfer-Encoding: 7bit
X-PMX-Version: 4.7.1.128075
X-from-outside-Cisco: [10.32.241.115]
X-Spam-Score: 0.0 (/)
X-Scan-Signature: 200d029292fbb60d25b263122ced50fc
Content-Transfer-Encoding: 7bit
Cc: pwe3@ietf.org
Subject: [PWE3] Re: comments on draft-ietf-pwe3-hdlc-ppp-encap-mpls-05.txt
X-BeenThere: pwe3@ietf.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Pseudo Wires Edge to Edge <pwe3.ietf.org>
List-Unsubscribe: <https://www1.ietf.org/mailman/listinfo/pwe3>, <mailto:pwe3-request@ietf.org?subject=unsubscribe>
List-Post: <mailto:pwe3@ietf.org>
List-Help: <mailto:pwe3-request@ietf.org?subject=help>
List-Subscribe: <https://www1.ietf.org/mailman/listinfo/pwe3>, <mailto:pwe3-request@ietf.org?subject=subscribe>
Sender: pwe3-bounces@ietf.org
Errors-To: pwe3-bounces@ietf.org
Stewart, Replies in line. ( note that the original e-mail never got to the pwe3 list , as you had the wrong e-mail address ) Luca Stewart Bryant wrote: > Please don't forget the comments at > > http://www.ietf.org/mail-archive/web/pwe3/current/msg07088.html > > > ------ > > Not sure that the following text add any value > > Although different layer 2 protocols require different information to > be carried in this encapsulation, an attempt has been made to make > the encapsulation as common as possible for all layer 2 protocols. > Other layer 2 protocols are described in separate documents. [ATM] > [ETHER] [FRAME] > yes, this is from the original draft-martini. I removed it. > ------ > > I note that you do not describe the layering in this draft, or > call it out explicitly. I think that you should import the layering > text from one of the other drafts to show PSN label/PW label/CW. > I added the text out of the ethernet , and ATM drafts. > ------ > > 0 1 2 3 > 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > |0 0 0 0|0 0 0 0|Res| Length | Sequence Number | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > Figure 2: MPLS PWE3 Control Word > > > I think that you should call out the field descriptions as per other > encaps, and include the definition. It's just cut and paste. I already do. what do you mean ? > > ------ > > In the above diagram the first 4 bits are set to 0 in indicate PW > data [ARCH]. > > Should be CW > so 0 indicates CW, ok. > ------- > > The next 4 bits provide space for carrying protocol specific flags. > These are not used for HDLC/PPP and they They MUST be set to 0 when > transmitting, and MUST be ignored upon receipt. > > Why is frag not supported? > because it is a separate draft. A long time ago , I made a decision , not to change all PWE3 drafts to accommodate the latest developments and additions to the protocol. Including fragmentation here would mean a normative reference to the fragmentation document. I would like to avoid that, > ------- > > 3.1.2. Processing the sequence number > > 3.2. MTU Requirements > > The network MUST be configured with an MTU that is sufficient to > transport the largest encapsulation frames. When MPLS is used as the > tunneling protocol, for example, this is likely to be 12 or more > bytes greater than the largest frame size. The methodology described > in [FRAG] MAY be used to fragment encapsulated frames that exeeed the > PSN MTU. However if [FRAG] is not used then if the ingress router > determines that an encapsulated layer 2 PDU exceeds the MTU of the > PSN tunnel through which it must be sent, the PDU MUST be dropped. > > So you do support frag, but you don't allocate the bits in Fig 2 > to avoid a normative reference .... > ------- > > If a packet is received, on the attachment circuit, that exceeds the > interface MTU paramater value [CONTROL] , it MUST be dropped. > > subTLV? > yes I messed this one . > -------- > > 4.2. Frame Relay Port Mode > > Figure 3 illustrates the concept of frame relay port mode or many- > to-one mapping which is an OPTIONAL capability. > > I think that the diagram needs a bit of a clean-up to make it > obvious there is a FIG 3a and a Fig 3b, it looks somewhat merged. > fixed. > -------- > > 5. Using an MPLS Label as the Demultiplexer Field > > To use an MPLS label as the demultiplexer field, a 32-bit label stack > entry [MPLSENCAP] is simply prepended to the emulated PW > encapsulation, and hence will appear as the bottom label of an MPLS > label stack. This label may be called the "PW label". The particular > emulated PW identified by a particular label value must be agreed by > the ingress and egress LSRs, either by signaling (e.g, via the > methods of [CONTROL]) or by configuration. Other fields of the label > stack entry are set as follows. > > I think that this text is missing from the ATM draft > ??? it might be , but that draft is done . > ---------- > > 7. Security Considerations > > The ethernet pseudowire type is subject to all of the general > > The HDLC/PPP PW > > --------- > > Regards > > Stewart > > > _______________________________________________ pwe3 mailing list pwe3@ietf.org https://www1.ietf.org/mailman/listinfo/pwe3
- [PWE3] comments on draft-ietf-pwe3-hdlc-ppp-encap… Stewart Bryant
- [PWE3] Re: comments on draft-ietf-pwe3-hdlc-ppp-e… Luca Martini