From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id 43dac640 for ; Mon, 4 Feb 2019 20:30:25 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id C54DE9B8A4; Tue, 5 Feb 2019 06:30:23 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 70DE69B892; Tue, 5 Feb 2019 06:29:51 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id EFE359B892; Tue, 5 Feb 2019 06:29:48 +1000 (AEST) Received: from mercury.lcs.mit.edu (mercury.lcs.mit.edu [18.26.0.122]) by minnie.tuhs.org (Postfix) with ESMTPS id 656D39B891 for ; Tue, 5 Feb 2019 06:29:48 +1000 (AEST) Received: by mercury.lcs.mit.edu (Postfix, from userid 11178) id 69A4818C082; Mon, 4 Feb 2019 15:29:47 -0500 (EST) To: tuhs@minnie.tuhs.org Message-Id: <20190204202947.69A4818C082@mercury.lcs.mit.edu> Date: Mon, 4 Feb 2019 15:29:47 -0500 (EST) From: jnc@mercury.lcs.mit.edu (Noel Chiappa) Subject: Re: [TUHS] OSI stack (Was: Posters) X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jnc@mercury.lcs.mit.edu Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" > From: Grant Taylor > I'm not quite sure what you mean by naming a node vs network interface. Does one name (in the generic high-level sense of the term 'name'; e.g. an 'address' is a name for a unit of main memory) apply to the node (host) no matter how many interfaces it has, or where it is/moves in the network? If so, that name names the node. If not... > But I do know for a fact that in IPv4, IP addresses belonged to the > system. No. Multi-homed hosts in IPv4 had multiple addresses. (There are all sorts of kludges out there now, e.g. a single IP address shared by a pool of servers, precisely because the set of entity classes in IPvN - hosts, interfaces, etc - and namespaces for them were not rich enough for the things that people actually wanted to do - e.g. have a pool of servers.) Ignore what term(s) anyone uses, and apply the 'quack/walk' test - how is it used, and what can it do? > I don't understand what you mean by using "names" for "path selection". Names (in the generic sense above) used by the path selection mechanism (routing protocols do path selection). > That's probably why I don't understand how routes are allocated by a > naming authority. They aren't. But the path selection system can't aggregate information (e.g. routes) about multiple connected entities into a single item (to make the path selection scale, in a large network like the Internet) if the names the path selection system uses for them (i.e. addresses, NSAP's, whatever) are allocated by several different naming authorities, and thus bear no relationship to one another. E.g. if my house's street address is 123 North Street, and the house next door's address is 456 South Street, and 124 North Street is on the other side of town, maps (i.e. the data used by a path selection algorithm to decide how to get from A to B in the road network) aren't going to be very compact. Noel