[netext] Review of draft-ietf-netext-logical-interface-support-04
Peter McCann <Peter.McCann@huawei.com> Wed, 07 March 2012 22:20 UTC
Return-Path: <Peter.McCann@huawei.com>
X-Original-To: netext@ietfa.amsl.com
Delivered-To: netext@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id ADB2911E80AE for <netext@ietfa.amsl.com>; Wed, 7 Mar 2012 14:20:33 -0800 (PST)
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 ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xFvLWArUoVhL for <netext@ietfa.amsl.com>; Wed, 7 Mar 2012 14:20:33 -0800 (PST)
Received: from dfwrgout.huawei.com (dfwrgout.huawei.com [206.16.17.72]) by ietfa.amsl.com (Postfix) with ESMTP id EEFAD11E8074 for <netext@ietf.org>; Wed, 7 Mar 2012 14:20:32 -0800 (PST)
Received: from 172.18.9.243 (EHLO dfweml201-edg.china.huawei.com) ([172.18.9.243]) by dfwrg02-dlp.huawei.com (MOS 4.2.3-GA FastPath) with ESMTP id ADW60447; Wed, 07 Mar 2012 17:20:32 -0500 (EST)
Received: from DFWEML407-HUB.china.huawei.com (10.193.5.132) by dfweml201-edg.china.huawei.com (172.18.9.107) with Microsoft SMTP Server (TLS) id 14.1.323.3; Wed, 7 Mar 2012 14:18:46 -0800
Received: from DFWEML504-MBX.china.huawei.com ([10.124.31.30]) by dfweml407-hub.china.huawei.com ([10.193.5.132]) with mapi id 14.01.0323.003; Thu, 8 Mar 2012 06:18:50 +0800
From: Peter McCann <Peter.McCann@huawei.com>
To: "telemaco.melia@alcatel-lucent.com" <telemaco.melia@alcatel-lucent.com>, "sgundave@cisco.com" <sgundave@cisco.com>
Thread-Topic: Review of draft-ietf-netext-logical-interface-support-04
Thread-Index: Acz8sEVnAgz12r8oSVucATDg6oXf5Q==
Date: Wed, 07 Mar 2012 22:18:50 +0000
Message-ID: <5963DDF1F751474D8DEEFDCDBEE43AE716448084@dfweml504-mbx>
Accept-Language: en-US, zh-CN
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [10.193.125.95]
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-CFilter-Loop: Reflected
Cc: "netext@ietf.org" <netext@ietf.org>
Subject: [netext] Review of draft-ietf-netext-logical-interface-support-04
X-BeenThere: netext@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: "Mailing list for discusion of extensions to network mobility protocol, i.e PMIP6. " <netext.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/netext>, <mailto:netext-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/netext>
List-Post: <mailto:netext@ietf.org>
List-Help: <mailto:netext-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/netext>, <mailto:netext-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 07 Mar 2012 22:20:33 -0000
In Taipei I picked up an action item to review the logical interface support draft. Here are some comments on it. In general, I think you need to consider some of the problems being dealt with in the MIF working group in the context of this document. Mapping IP flows onto physical interfaces is just one of the things that you have to worry about. What if each physical interface is connected to a different provisioning domain? How do you deal with things like multiple sets of DNS servers, or conflicting DHCP options? I am not sure what is gained by using a logical interface as depicted in Figure 5 of Section 6.1. There are two different prefixes here (why are we going back to a single LMA at all in this case?) so you might as well have presented this as two different interfaces to the upper layers. I think the use cases in Section 6.2 and 6.3 were more what the authors had in mind when thinking about this logical interface concept. However, I have a concern: in these cases, you need to know that the two physical interfaces are being routed by the network back to the same LMA. In general, the two technologies may be routed to completely different service providers. How does the logical interface manager in the host distinguish these two cases? By its very definition, PMIP does not expose the workings of the network to the host. Are you saying that a given host will only use its WLAN interface in conjunction with a wide-area cellular operator? That doesn't seem very realistic given today's usage models, where I can take my phone into my home and use my home WLAN network. Section 4, I am not sure about your description of the 3GPP link layer. As shown in your protocol stack in Figure 2, there is no PPP, although it is true that the concatenation of PDCP and GTP makes for a point-to-point link. Also, you should make it clear that the random L2 MAC address is only used in the Source Link Layer Address *option* of ND, and not as a true link layer source address (there is no place in the PDCP headers to put such a thing). I believe this address is simply ignored by the PGW since it has a tunnel endpoint associated with the UE. Editorial nits: Section 3.2.1: This type of solution does not typically allow for simultaneous attachment to different access networks, and therefore can only be considered for inter-access technology handovers, but not for flow mobility. I think you meant to say: This type of solution does not typically allow for simultaneous attachment to different access networks, and therefore can only be considered for intra-access technology handovers, and not for flow mobility. In Section 5.6: s/PIF Table/FLOW Table/ -- Peter J. McCann Huawei Technologies (USA) Peter.McCann@Huawei.com +1 908 541 3563 Rm. C-0105, 400 Crossings Blvd. (2nd floor), Bridgewater, NJ 08807-2863 USA
- [netext] Review of draft-ietf-netext-logical-inte… Peter McCann
- Re: [netext] Review of draft-ietf-netext-logical-… Sri Gundavelli