Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!amdcad!ames!ucbcad!ucbvax!XX.LCS.MIT.EDU!JTW From: JTW@XX.LCS.MIT.EDU (John Wroclawski) Newsgroups: comp.protocols.tcp-ip Subject: Re: RCTE Message-ID: <12338653476.59.JTW@XX.LCS.MIT.EDU> Date: Wed, 30-Sep-87 01:27:51 EDT Article-I.D.: XX.12338653476.59.JTW Posted: Wed Sep 30 01:27:51 1987 Date-Received: Sun, 4-Oct-87 19:42:25 EDT References: Sender: daemon@ucbvax.BERKELEY.EDU Organization: The ARPA Internet Lines: 32 Hmm. The basic SUPDUP protocol doesn't address the remote echoing overhead problem at all, and won't do a thing for those paying per-packet charges, which is how this all started. Some (long) time ago Richard Stallman designed and implemented an extension called the SUPDUP Local Editing Protocol, which allowed a remote display-oriented program, such as EMACS, to arrange to have most operations performed at the user's local terminal, with information transferred to the remote end as required. This vastly reduces the need to send screen update information over the net, and allows bunching of update information into a few large packets rather than zillions of one-character ones. Network utilization is improved in both directions. This protocol was documented in at least one MIT AI Lab memo. I think the final version of the AI memo that described SUPDUP included it also. SUPDUP LEP is to some extend a superset of the functionality of RCTE, and could be useful for reducing the load caused by non-display-oriented programs. The basic SUPDUP protocol has some very good ideas about how to do virtual terminals, but could use some updating. A new protocol could be based on the structure of SUPDUP, maintaining the LEP and input processing concepts, but with a newer set of capability descriptors in the startup negotiation and output encodings based on the ANSI X3.64 terminal standards. This protocol would nicely address both the network efficiency concerns raised here and the problems which come up using arbitrary window-based emulators as remote terminals. -------