Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!linus!philabs!cmcl2!floyd!harpo!seismo!hao!hplabs!sri-unix!jrodrig@mitre-gateway From: jrodrig%mitre-gateway@sri-unix.UUCP Newsgroups: net.micro.pc Subject: LANs Message-ID: <15901@sri-arpa.UUCP> Date: Mon, 23-Jan-84 16:22:59 EST Article-I.D.: sri-arpa.15901 Posted: Mon Jan 23 16:22:59 1984 Date-Received: Fri, 27-Jan-84 10:42:56 EST Lines: 58 From: jose rodriguez Well, I can give you some info on LANs because we have installed several on DOD sites. Let me answer your questions: 1) Yes, TCP/IP can run on LANs (baseband or broadband -- it is immaterial to base/broad what layers you have above the datalink (I think). As a matter of fact some people are putting baseband nets into broadband channels through 10Mhz modems (a really neat idea) (you see, there is no standard for broadband datalink layer). As a matter of fact, I would say that the faster the LAN is, the less important the size of packets is (what really counts is the number of packets -- but this is an extremelly complex problem...). (If anyone has hard facts, please come forth.) 2) "If a LAN supports TCP/IP" actually is the nodes that support TCP/IP. You mentioned servers vs. terminals. Well, there is something in the middle: the user-side of protocols. All protocols have two sides: user (driven by the person) and server (waiting for connections across the net). The user side can be made considerably simpler (and in my opinion, better) which makes them feasible for pc's (the 8088 is slow, but not THAT slow...). There are other schemes to make implementations perform reasonably (for a single user) on PCs. Now "...have to support ...FTP,TN..." well why have TCP/IP, etc.? If you mean less powerful applications, that's a good idea. The CSG group at MIT have done such work, particularly they have a TFTP (T for trivial) which only needs one TCP channel. 3) "...expect...8088..." Well, if you design it right, why not? Look at it as a challenge. (We think it is feasible). "...single tasking..." I would rather have a monolithic program that takes over the pc than some scheduler coming around and bothering. I can implement my own multi-task OS for the pc more suitable for real time needs. You see, our Suns 1.0 have a performance far worse than pc's... think about that.... 3Com's Ethernet has a lot added to Ethernet (a remote procedure call protocol and a byte stream protocol based on the XNS (from Xerox) family of protocols). The same (or similar) functionality is provided by other PC vendors but the problem is they all are incompatible! "That's fine, you know, for our needs...", well what happens when your supplier goes under? Or if you want to add someone else's equipment (say a 68k workstation) not supported by your network vendor? Actually, I am being a little too hard on 3Coms equipment. As a matter of fact I think their protocols can easily coexist with Telnet, FTP, etc. (if it wasn't for their hardware, but that is a different story...). What does TCP/IP buy me? Well being able to hop to our LAN, go through a gateway, into the Arpanet, go through a MIT gateway and login to my old job's host machine. If you have any questions don't hesitate sending mail directly to me. Jose