Browse Prior Art Database

Thinwire protocol for connecting personal computers to the Internet (RFC0914) Disclosure Number: IPCOM000004325D
Original Publication Date: 1984-Sep-01
Included in the Prior Art Database: 2000-Oct-05
Document File: 19 page(s) / 55K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

D.J. Farber: AUTHOR [+3]


file transfer and one-time inquiries to time, date, or quote-of-the-day servers).

This text was extracted from a ASCII Text document.
This is the abbreviated version, containing approximately 5% of the total text.

Network Working Group David J. Farber

Request for Comments: 914 Gary S. Delp

Thomas M. Conte

University of Delaware

September 1984

A Thinwire Protocol

for connecting personal computers


Status of this Memo

This RFC focuses discussion on the particular problems in the

ARPA-Internet of low speed network interconnection with personal

computers, and possible methods of solution. None of the proposed

solutions in this document are intended as standards for the

ARPA-Internet. Rather, it is hoped that a general consensus will

emerge as to the appropriate solution to the problems, leading

eventually to the adoption of standards. Distribution of this memo


What is the Problem Anyway ?

As we connect workstations and personal computers to the INTERNET,

many of the cost/speed communication tradeoffs change. This has made

us reconsider the way we juggle the protocol and hardware design

tradeoffs. With substantial computing power available in the $3--10K

range, it is feasible to locate computers at their point of use,

including in buildings, in our homes, and other places remote from

the existing high speed connections. Dedicated 56k baud lines are

costly, have limited availability, and long lead time for

installation. High speed LAN's are not an applicable interconnection

solution. These two facts ensure that readily available 1200 / 2400

baud phone modems over dialed or leased telephone lines will be an

important part of the interconnection scheme in the near future.

This paper will consider some of the problems and possibilities

involved with using a "thin" (less than 9600 baud) data path. A trio

of "THINWIRE" protocols for connecting a personal computer to the

INTERNET are presented for discussion.

Although the cost and flexibility of telephone modems is very

attractive, their low speed produces some major problems. As an

example, a minimum TCP/IP Telnet packet (one character) is 41 bytes

long. At 1200 baud, the transmission time for such a packet would be

around 0.3 seconds. This is equivalent to using a 30 baud line for

single character transmission. (Throughout the paper, the assumption

is made that the transmission speed is limited only by the speed of

the communication line. We also assume that the line will act as a

synchronous link when calculating speed. In reality, with interrupt,

computational, and framing overhead, the times could be 10-50%


In many cases, local echo and line editing can allow acceptable

RFC 914 September 1984

Thinwire Protocol

Telnet behavior, but many applications wil...