From owner-diff-serv@BayNetworks.COM Wed Jun 10 12:45:27 1998 Delivery-Date: Wed, 10 Jun 1998 12:45:33 -0400 Return-Path: owner-diff-serv@BayNetworks.COM Received: from smtp-gw.BayNetworks.COM (ns2.BayNetworks.COM [134.177.3.16]) by ietf.org (8.8.5/8.8.7a) with ESMTP id MAA23578 for ; Wed, 10 Jun 1998 12:45:27 -0400 (EDT) Received: from mailhost.BayNetworks.COM (screen2r.BayNetworks.COM [134.177.3.1]) by smtp-gw.BayNetworks.COM (8.8.8/8.8.8) with ESMTP id JAA10643; Wed, 10 Jun 1998 09:41:37 -0700 (PDT) Received: from majordomo.BayNetworks.COM ([192.32.253.10]) by mailhost.BayNetworks.COM (8.8.8/8.8.8) with ESMTP id JAA04315; Wed, 10 Jun 1998 09:41:17 -0700 (PDT) Received: (from major@localhost) by majordomo.BayNetworks.COM (8.8.6/BNET-SVR4) id MAA14195; Wed, 10 Jun 1998 12:45:16 -0400 (EDT) for diff-serv-outgoing X-Authentication-Warning: majordomo.BayNetworks.COM: major set sender to owner-diff-serv@majordomo using -f Received: from mailhost.BayNetworks.COM ([132.245.135.115] (may be forged)) by majordomo.BayNetworks.COM (8.8.6/BNET-SVR4) with ESMTP id MAA14191; Wed, 10 Jun 1998 12:45:09 -0400 (EDT) for Received: from majordomo.BayNetworks.COM ([192.32.253.10]) by mailhost.BayNetworks.COM (8.8.8/8.8.8) with ESMTP id MAA10099 for ; Wed, 10 Jun 1998 12:34:27 -0400 (EDT) Received: from smtp-gw.BayNetworks.COM (ns1.BayNetworks.COM [134.177.3.20]) by majordomo.BayNetworks.COM (8.8.6/BNET-SVR4) with ESMTP id MAA14187; Wed, 10 Jun 1998 12:44:36 -0400 (EDT) for Received: from arthur.axion.bt.co.uk (arthur.axion.bt.co.uk [132.146.5.4]) by smtp-gw.BayNetworks.COM (8.8.8/8.8.8) with ESMTP id JAA15761 for ; Wed, 10 Jun 1998 09:33:18 -0700 (PDT) Received: from rambo (actually rambo.futures.bt.co.uk) by arthur.axion.bt.co.uk (PP) with SMTP; Wed, 10 Jun 1998 17:32:31 +0100 Received: from mussel.futures.bt.co.uk (actually mussel) by rambo with SMTP (PP); Wed, 10 Jun 1998 17:34:08 +0100 Received: by mussel.futures.bt.co.uk with Microsoft Exchange (IMC 4.0.837.3) id <01BD9495.4CC48F30@mussel.futures.bt.co.uk>; Wed, 10 Jun 1998 17:29:19 +0100 Message-ID: From: Martin Tatham To: "'Diffserv'" Subject: End-to-end preservation of DS-codes Date: Wed, 10 Jun 1998 17:33:27 +0100 X-Mailer: Microsoft Exchange Server Internet Mail Connector Version 4.0.837.3 Sender: owner-diff-serv@BayNetworks.COM Precedence: bulk >(Please excuse the following if it's re-opening too many threads which >have been shut down ...) > >I think there was an agreed need for global DS-codes which are >preserved end-to-end, but previous discussion (reasonably) seems to >have moderated this by the need to conform to hop-by-hop SLAs. > >I believe that the basic requirement still exists, both(a) to preserve >end-to-end semantics >(b) to give better migration path, in the sense of 'signalling' between >physically separate networks or between DS-capable islands. > >I don't know whether this is explicitly covered by any of the existing >proposals, but I'd like comments on the following: > >For certain PHB groups for which end-to-end preservation is required, >assume a DS-field structure: > >PPPGGG[CU] > >where >G is a globally-preserved part of the PHB >P is a local 'weighting' of the PHB. > >Within these PHB groups, providers may reset the P bits to conform with >SLAs, and PPP=000 may be taken to mean 'treat as BE' (similar to David >Black's proposal earlier). Assuming that no providers today treat >traffic differentially based on bits 3-7, there is no reason why non-DS >domains should not transparently carry the GGG bits (whether they have >deployed local precedence services or not). I think this would also >embrace the need for backwards compatibility (with GGG = 000), if it >was acceptable that the first three bits be interpreted as local. > >Note that I am not arguing for a structuring of all PHBs in this way, >just certain values of bits 3-5, and it would seem best to choose those >values which are rarely used today. (To conform to the dsopdef draft, >bit 5 could take value either 0 or 1 depending on whether the codepoint >group was adopted as standard or was experimental). > >One problem with the above is the legacy traffic which is marked with >non-zero TOS-code (i.e. bits 3-6). There are options do deal with this, >but that's another discussion ... > >The above structure would just seem to ease initial deployment. At a >later date, other codepoints with different structure could added, with >agreed end-to-end semantics - (e.g. 11100000 might be a good candidate, >with all bits being globally preserved). > >Regards, > >Martin >____________________________ >Martin Tatham >Internetworking Team >MLB G pp8, BT Laboratories >Ipswich, U.K. >Tel: +44-1473-606349 >Fax: +44-1473-606727 >martin.tatham@bt-sys.bt.co.uk >____________________________ >________________________________________________________ >Notice: This contribution is the personal view of the author and does >not > necessarily reflect the technical nor commercial direction of British >Telecommunications plc. >________________________________________________________ > From owner-diff-serv@BayNetworks.COM Mon Jun 22 11:58:11 1998 Delivery-Date: Mon, 22 Jun 1998 11:58:12 -0400 Return-Path: owner-diff-serv@BayNetworks.COM Received: from smtp-gw.BayNetworks.COM (ext-ns4.baynetworks.com [192.32.253.7]) by ietf.org (8.8.5/8.8.7a) with SMTP id LAA03328 for ; Mon, 22 Jun 1998 11:58:10 -0400 (EDT) Received: from mailhost.BayNetworks.COM ([132.245.135.115]) by smtp-gw.BayNetworks.COM (8.8.8/8.8.8) with ESMTP id LAA23202; Mon, 22 Jun 1998 11:54:22 -0400 (EDT) Received: from majordomo.BayNetworks.COM ([192.32.253.10]) by mailhost.BayNetworks.COM (8.8.8/8.8.8) with ESMTP id LAA15011; Mon, 22 Jun 1998 11:53:49 -0400 (EDT) Received: (from major@localhost) by majordomo.BayNetworks.COM (8.8.6/BNET-SVR4) id LAA24624; Mon, 22 Jun 1998 11:56:53 -0400 (EDT) for diff-serv-outgoing X-Authentication-Warning: majordomo.BayNetworks.COM: major set sender to owner-diff-serv@majordomo using -f Received: from mailhost.BayNetworks.COM (h016b.s86b1.BayNetworks.COM [134.177.1.107] (may be forged)) by majordomo.BayNetworks.COM (8.8.6/BNET-SVR4) with ESMTP id LAA24620; Mon, 22 Jun 1998 11:56:47 -0400 (EDT) for Received: from majordomo.BayNetworks.COM ([192.32.253.10]) by mailhost.BayNetworks.COM (8.8.8/8.8.8) with ESMTP id IAA14917 for ; Mon, 22 Jun 1998 08:48:27 -0700 (PDT) Received: from smtp-gw.BayNetworks.COM (ext-ns3.baynetworks.com [192.32.253.3]) by majordomo.BayNetworks.COM (8.8.6/BNET-SVR4) with ESMTP id LAA24611; Mon, 22 Jun 1998 11:56:14 -0400 (EDT) for Received: from mercury.Sun.COM (mercury.Sun.COM [192.9.25.1]) by smtp-gw.BayNetworks.COM (8.8.8/8.8.8) with SMTP id LAA24268 for ; Mon, 22 Jun 1998 11:48:26 -0400 (EDT) Received: from Central.Sun.COM ([129.152.1.7]) by mercury.Sun.COM (SMI-8.6/mail.byaddr) with SMTP id IAA15309; Mon, 22 Jun 1998 08:47:51 -0700 Received: from rigel.Central.sun.com by Central.Sun.COM (SMI-8.6/SMI-5.3) id KAA10249; Mon, 22 Jun 1998 10:47:23 -0500 Received: from sun.com (marx [129.152.172.13]) by rigel.Central.sun.com (8.7.6/8.7.3) with ESMTP id JAA21711; Mon, 22 Jun 1998 09:46:42 -0600 (MDT) Message-ID: <358E7C83.C194852B@sun.com> Date: Mon, 22 Jun 1998 09:47:15 -0600 From: "Mark A. Carlson" Reply-To: mark.carlson@Sun.COM Organization: Sun Microsystems X-Mailer: Mozilla 4.04 [en] (WinNT; U) MIME-Version: 1.0 To: Diffserv Framework Document List , Differentiated Services Working Group Subject: Framework Document Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-diff-serv@BayNetworks.COM Precedence: bulk At the interim meeting it was decided that the Framework draft needed more work, so I will be keeping the framework doc mailing list open for a while longer (DSFramework@redcape.com). Dinesh (dverma@watson.ibm.com) is working on a revision as we speak and will post an update soon. In the meantime, send him your comments and proposed revisions so he can incorporate them. If you are not on the list already and would like to work on improving the document, send me email at mac@redcape.com and ask to subscribe to the DSFramework mailing list. Or if you are on this list and want off, ditto. These are the people on the list so far: slblake@raleigh.ibm.com, d.black@opengroup.org, brian@hursley.ibm.com, Kathleen_Nichols@BayNetworks.COM, mborden@BayNetworks.COM, raj.yavatkar@intel.com, rbonica@mci.net, jagan@baynetworks.com, pan@watson.ibm.com, shivkuma@ecse.rpi.edu, yoramb@microsoft.com, wuchang@eecs.umich.edu, James_Binder@3com.com, dovrolis@hertz.ece.wisc.edu, zhwang@lucent.com, Borje.Ohlman@ericsson.com, wweiss@lucent.com, E.B.Davies@nortel.co.uk, dverma@watson.ibm.com, mfalou@cs.toronto.edu, ben@advanced.org, lixia@cs.ucla.edu, jfu@netcoresys.com, mac@redcape.com -- mark