NIST reference ANSI X3.100-1989 PUBLICATIONS ADOPTED FOR USE BY THE FEDERAL GOVERNMENT Wtr£ PUB 100-1 SEE NOTICE ON INSIDE for Information Systems - Interface between Data Terminal Equipment (DTE) and Data Circuit-Terminating Equipment (DCE) for Operation with Packet-Switched Data Networks (PSDN), or # between Two DTEs, by Dedicated Circuit X3.100-1989 ANSI -JK 468 . A8A3 American National Standards Institute 1430 Broadway #100-1 lyiiii New York , New York 1991 /{)()/(} This standard has been adopted for Federal Government use. Details concerning its use within the Federal Government are contained in Federal Information Processing Standards Publication 100-1, Interface Between Data Terminal Equipment (DTE) and Data Circuit- Terminating Equipment (DCE) for Operation with Packet-Switched Data Networks (PSDN), or Between Two DTEs, by Dedicated Circuit. For a complete list of the publications available in the Federal Informa¬ tion Processing Standards Series, write to the Standards Processing Coordinator (ADP), National Institute of Standards and Technology, Gaithersburg, MD 20899. ANSI® X3.100-1989 Revision of ANSI X3.100-1983 American National Standard for Information Systems - Interface between Data Terminal Equipment (DTE) and Data Circuit-Terminating Equipment (DCE) for Operation with Packet-Switched Data Networks (PSDN), or between Two DTEs, by Dedicated Circuit Secretariat Computer and Business Equipment Manufacturers Association Approved March 31,1989 American National Standards Institute, Inc American Approval of an American National Standard requires verification by ANSI that the requirements for due process, consensus, and other criteria for approval have been met by National the standards developer. Standard Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement means much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that a concerted effort be made toward their resolution. The use of American National Standards is completely voluntary; their existence does not in any respect preclude anyone, whether he has approved the standards or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standards. The American National Standards Institute does not develop standards and will in no circumstances give an interpretation of any American National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. Requests for interpretations should be addressed to the secretariat or sponsor whose name appears on the title page of this standard. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken periodically to reaffirm, revise, or withdraw this standard. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute. Published by American National Standards Institute 1430 Broadway, New York, New York 10018 Copyright © 1989 by American National Standards Institute All rights reserved. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior written permission of the publisher. Printed in the United States of America APS1M491/18 Foreword (This Foreword is not part of American National Standard X3.100-1989.) This standard was developed by Task Group X3S3.7, Public Digital Network Access, in close cooperation with the International Telegraph and Telephone Consultative Committee (CCITT) and the International Organization for Standardization (ISO). Task Group X3S3.7 started its work on public data network access protocols in 1973 and contributed to the international work of CCITT and ISO in this area. Work in CCITT on packet-switching technology also advanced at this time and was highlighted by the adoption, in 1976, of Recommendation X.25. Work has continued to refine Recommendation X.25 over the last twelve years, culminating with the approval of the 1988 version of Recommendation X.25 by CCITT at its Plenary Assembly in October 198S. In 1981, ISO, seeing the need for a terminal-oriented counterpart to Recom¬ mendation X.25, started work on standards that became known as ISO 7776 (corresponding to the data link layer of Recommendation X.25) and ISO 8208 (corresponding to the packet layer). Task Group X3S3.7 was responsible for significant input to both efforts. To meet the unique requirements of the US environment for signaling speeds and optional user facilities, for example, the task group determined that Recom¬ mendation X.25 should serve as the basis for an American National Standard. Such a standard was adopted in 1983 as ANSI X3.100-1983. With the continuing work in both CCITT and ISO, work was started in 1985 to revise ANSI X3.100-1983. The draft revised American National Standard was submitted to Technical Committee X3S3 to start the approval process according to ANSI procedures. The process was successfully completed, resulting in revised ANSI X3.100-1989. Suggestions for improvement of this standard will be welcome. They should be sent to the Computer and Business Equipment Manufacturers Association, 311 First Street, NW, Suite 500, Washington, DC 20001. This standard was processed and approved for submittal to ANSI by the Accredited Standards Committee on Information Processing Systems, X3. Committee approval of this standard does not necessarily imply that all committe members voted for its approval. At the time it approved this standard, the X3 Committee had the following members: Richard Gibson, Chair Donald C. Loughry, Vice-Chair Catherine A. Kachurik, Administrative Secretary Organization Represented Name of Representative Allen-Bradley Company . Ronald H. Reimer American Library Association . Paul Peters American Nuclear Society. Geraldine C. Main AMP Inc. Edward Kelly Ronald Lloyd (All) Apple. Jean Luc LeBrun Michael J. Lawler (Alt) Association of the Institute for Certification of Computer Professionals . Thomas M. Kurihara AT&T . Thomas F. Frost Paul D. Bartoli (Alt) Boeing Company. Paul W. Mercer Organization Represented Name of Representative Compaq Computer Corporation.. James Barnes Control Data Corporation.. Ernest Fogle Cooperating Users of Burroughs Equipment . Thomas Easterday Donald Miller (Alt) Dataproducts Corporation.. Charles D. Card Digital Equipment Computer Users Society . James Ebright Digital Equipment Corporation . Gary S. Robinson Delbert L. Shoemaker (All) Eastman Kodak. Gary Haines James D. Converse (Alt) Electronic Data Systems Corporation. Jerrold S. Foley GUIDE International. Frank Kirshenbaum Sandra Swartz Abraham (All) Hewlett-Packard. Donald C. Loughry Honeywell Bull . David M. Taylor IBM Corporation. Mary Anne Gray Robert H. Follett (All) IEEE Computer Society. Tom Hannon Bob Pritchard (Alt) Lawrence Berkeley Laboratory. David F. Stevens Robert L. Fink (Alt) MAP/TOP. (Representation Vacant) Mike Kaminski (Alt) Moore Business Forms. Delmer H. Oddy National Communications System. Dennis Bodson Donald Wilson (Alt) National Institute of Standards and Technology Robert E. Roundtree Mike Hogan (Alt) NCR Corporation . Tom Kern A. R. Daniels (Alt) OMNICOM . Harold C. Folts Cheryl Slobodian (Alt) Prime Computer, Inc. Arthur Norton Recognition Technology Users Association . Herbert F. Schantz SHARE, Inc. Thomas B. Steel Gary Ainsworth (Alt) 3M Company. Paul D. Jahnke Unisys . Marvin W. Bass Steven Oksala (Alt) U.S. Department of Defense. William C. Rinehuls Thomas H. Kurihara (Alt) U.S. General Services Administration. Dale O. Christensen Larry L. Jackson (Alt) US WEST. Gary Dempsey Sue Caparo (Alt) VIM. Chris Tanner John Ulrich (Alt) Wang Corporation. J. J. Cinecoe Sarah Wagner (Alt) Wintergreen Information Services. John L. Wheeler Xerox Corporation. Roy Pierce Subcommittee X3S3 on Data Communications, which developed this standard, had the following members: W. F. Emmons, Chair H. V. Bertine E. Harris D. D. Wilson, Vice-Chair D. R. Cairnes P. W. Kicsling F. Chandler G. Lawrence J. R. Cartwright J. P. Oliveto A. L. Chapin F. Piper D. M. Chitre L. Sage W. Clausen T. Shanahan J. W. Conway R. G. Spusta K. L. Dally D. Walters J. R. Ebright J. L. Wheeler M. Griefner F. J. Worthington Task Group X3S3.7, Public Digital Network Access, which had technical responsibility for the development of this standard, had the following members: Fred M. Burg, Chair Brian Borchers Bill Jerome Randall G. Spusta, David J. Carballal Gary Kessler Frank H. Chandler, Jr. Vice-Chair Pierre Lin William Dalton Whitney Myers Mark Knopper, Secretary Dennis Ernst J. Podvojsky William J. Ingram, Editor John C. Gibson Ted Rich Neville L. Golding Laurie Sage Edward Greene Joel M. Snyder Jack Himeisen David Spence Sidney H. Sternick Other persons who contributed to the development of this standard were: Paul W. Campbell, Jr. Kathy L. Dally Trevor Davies Donald Glen Dan Grossman Gerald Hoover Tom Jenkins Dave Kelly Richard B. Rubin Mehmet Ulema Michael Wong Contents SECTION PAGE 1. Scope . 7 2. Referenced and Related Standards and Publications. 7 2.1 Referenced American National Standards. 7 2.2 Other Referenced Standards. S 2.3 Related Publication. 9