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Inter-Entity Communication - an experiment (RFC0441)

IP.com Disclosure Number: IPCOM000003597D
Original Publication Date: 1973-Jan-01
Included in the Prior Art Database: 2019-Feb-12
Document File: 7 page(s) / 9K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

R.D. Bressler: AUTHOR [+1]

Related Documents

10.17487/RFC0441: DOI

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 38% of the total text.

Network Working Group Bob Bressler Request for Comments: 441 Bob Thomas NIC 13773 January 19, 1973

Inter-Entity Communication - An Experiment

This note is an attempt to be a status report concerning an experiment based on the desire of users, at their consoles, to converse with one another, and perhaps to get some debugging assistance. The user might ask: "who can I talk to"; "can I show him what I have done", and "can I let him run my program?" Many time sharing systems provide capabilities such as these, within the bounds of their system. Almost all systems have a "WHO" or "SYSTAT", many have commands like "LINK" or "TALK", and some support more esoteric capabilities like controlling another user’s program. At the last formal meeting of the Network Working Group, in October of 1971 at MIT, a group got together to talk about these features for Inter Entity Communications (IEC), and how they might be extended to span across Host boundaries.

Subsequent development has proceeded in an ad hoc manner. The general design philosophy paralleled that of TELNET in terms of having both server and user programs. The server program would handle commands like "connect to user FOO", "where is user BAR", or "who is on your system?" An initial implementation of a server and user was brought up at MIT-DMCG, using a completely arbitrary protocol. Soon after that, in an effort to increase its usefulness, the protocol was modified to be compatible with that being used by the Resource Sharing Executive being developed at BBN-TENEX.

The MIT user program used the concept of "ports" to help identify character streams entering and leaving an object. A pictorial diagram follows (FIGURE 1) showing a user teletype, his job and two consultants with whom he is conversing.

Bressler & Thomas [Page 1]

RFC 441 Inter-Entity Communication January 1973

+------+ | USER | | TTY | +------+ | | -------------|---|--------------+ | | | +-------+ +------------------+ | | HOST | | COMMAND | | | A | | INTERPRETER | | +-------+ +---+-+-------+-+--+ | | TTY |_| |_| TTY | | OUT-PORT ^ | IN-PORT | | | | | | | V | +--------------+ | +-|-+ | | <----| |IN-PORT |--+ +-|-+ | | | CONSULTANT | | | #1 | +-|-+ | I.E.C. ---->| |OUT-PORT | +-|-+ | | +--------------+ | | +--------------+ +-|-+ | <----| |IN-PORT |--+ +-|-+ | | | | CONSULTANT | | | | #2 | | +-|-+ | | ^ | ---->| |OUT-PORT | | | | +-|-+ | | JOB | V JOB | +--------------+ | IN-PORT+--+ +--+OUT-PORT | | -----|--|-------|--|----------+ | +----+ +-------+ +---------+ | | | +------+ | USER JOB | | HOST | | B | +------+

The user now has the option of opening or closing any of the ports he wishes. While in conversation mode, he might turn off the ports leading to the JOB. If he wished consultant 1 to control the job, he might turn off the input ports from his own TTY and from consultant 2.

Bressler & Thomas [Page 2]

RFC 441 Inter-Entity Communication January 1973

Towards this goal, the user interface provides the following set of commands:

WHO use...

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