Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!floyd!harpo!seismo!hao!hplabs!sri-unix!ron@brl-vgr From: ron%brl-vgr@sri-unix.UUCP Newsgroups: net.unix-wizards Subject: Re: TCP/IP (Re: VMS talking to UNIX) Message-ID: <17541@sri-arpa.UUCP> Date: Tue, 13-Mar-84 22:00:10 EST Article-I.D.: sri-arpa.17541 Posted: Tue Mar 13 22:00:10 1984 Date-Received: Fri, 16-Mar-84 02:54:18 EST Lines: 30 From: Ron NatalieDECNet and TCP/IP are both different upper level protocols. They both handle a variety of network hardware. TCP/IP just carries on a bit farther. The Internet Protocol (IP) is a Department of Defense standard network protocol that allows any two hosts on any network to talk to each other. The Internet Community is composed of over 100 active nets which include the ARPANET and MILNET. Users on different networks communicate trans- parently with each other do to magic in IP and computers called gateways. TCP is the Transmission Control Protocol. It essentially takes packets and turns them in to reliable virtual circuits (like unix pipes between machines). On top of TCP there are Virtual Terminal (telnet), file transfer, and Mail protocols. All this means is sitting in my office, I can type "telnet UCLA-CCN" and then start logging in to an IBM in California. This goes through a couple of local area nets here and accoss the MILNET to the ARPANET to UCLA. DECNet sort of does this provided you are using DEC machines and DEC network hardware. TCP/IP is available on all DEC machines and nearly every operating system that will run on them, IBM's (both mainframes and the PC), UNIVACs, Honeywells, and most anything that runs Unix (Gould, Pyramid, Suns, and most of your smarter micros). It allows use of the ARPANet style BBN Packet Switches, Ethernets, and a who slew of more exotic networking hardware. In addition, zapping around the country on a network that your tax dollars paid for is a little self satisfying (do that on DECNET!). I hope this helps. -Ron