X/Open Single Sign-on Service (XSSO) -<br> Pluggable Authentication Modules
X/Open Single Sign-on Service (XSSO) -
Pluggable Authentication Modules
Copyright © 1997 The Open Group


Preliminary Specification
X/Open Single Sign-on Service (XSSO) - Pluggable Authentication Modules
X/Open Document Number: P702
ISBN: 1-85912-144-6

©June 1997, The Open Group All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the copyright owners.

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This Document
This document is a Preliminary Specification (see above).
Typographical Conventions
The following typographical conventions are used throughout this document:


KerberosTM; is a trademark of the Massachusetts Institute of Technology.

Motif®, OSF/1®, and UNIX® are registered trademarks and the IT DialToneTM;, The Open GroupTM;, and the "X Device"TM; are trademarks of The Open Group.


The Open Group acknowledges contributions to the development of this specification by many members of The Open Group Security Program Group in providing additional material and reviewing drafts.

Referenced Documents

The following documents are referenced in this specification:


CESG Memorandum No.1, Issue 1.2, October 1992, Glossary of Security Terminology.

Federal Criteria

Federal Criteria Version 1.0, December 1992, Federal Criteria for Information Technology Security.

ISO/IEC 10181

ISO/IEC 10181, Information Technology - Open Systems Interconnection - Security Frameworks in Open Systems:
10181-1, Part 1: Security Frameworks Overview 10181-2, Part 2: Authentication Framework 10181-3, Part 3: Access Control 10181-4, Part 4: Non-repudiation Framework 10181-5, Part 5: Integrity Framework 10181-6, Part 6: Confidentiality Framework 10181-7, Part 7: Security Audit Framework

ISO/IEC 7498-2

ISO/IEC 7498-2:1989, Information Processing Systems - Open Systems Interconnection - Basic Reference Model - Part 2: Security Architecture.


Information Technology Security Evaluation Criteria, Provisional Harmonised Criteria, June 1991, Version 1.2, published by the Commission of the European Communities.

OSF RFC 86.0

OSF RFC 86.0. October 1995, Unified Login with Pluggable Authentication Modules (PAM).

PAM Manual

Sun Microsystems Inc., PAM Reference Manual Pages.


IEEE Std 1003.0/D15, June 1992, Draft Standard for Information Technology - Portable Operating System Interface (POSIX) - Part 0.

RFC 1510

Internet Proposed Standard, The Kerberos Network Authentication System, John Kohl, B.Clifford Neuman, Issue 5.2, 21 April 1993.

The following Open Group documents are referenced in this specification:


CAE Specification, December 1995, Generic Security Service API (GSS-API) Base (ISBN: 1-85912-131-4, C441).


Guide, December 1994, Distributed Security Framework (ISBN: 1-85912-071-7, G410).

The following document is useful background reading:

Lai and Samar

Charlie Lai and Vipin Samar, Making Login Services Independent of Authentication Technologies, 1996.

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