Systems Management; Event Management Service (XEMS)
Copyright © 1997 The Open Group


Preliminary Specification
Systems Management: Event Management Service
X/Open Document Number: P437
ISBN: 1-85912-132-2

©February 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
In a world of increasingly complex and distributed computer systems an effective Event Management Service (EMS) is a key part of the necessary systems management and administration infrastructure. The EMS must provide timely warning of impending problems, notify failing processes, identify problem areas in a system and possibly automatically fix them before service availability falls below acceptable levels. To achieve what is required, interoperability between systems in a distributed working environment is only part of the solution; inter-comprehension of the key event data is also necessary.

This Event Management Service (XEMS) specification defines a programming interface which receives notifications in the form of events, and transports them reliably to applications.

The specification is in 3 parts. The first part describes the generic XEMS API, including the model, architecture, positioning of XEMS in the systems management domain, the data formats used by XEMS, and the definitions for the XEMS interfaces (Registration, Event Type, Event Filter, Consumer, Supplier, Administration, Command Line). The second part describes reference implementations for DCE and CORBA environments. The third part describes event structures for the basic event set.

The structure of this specification is as follows:

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Referenced Documents

The following documents are referenced in this specification:


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


CAE Specification, July 1994, The Common Object Request Broker: Architecture and Specification (ISBN: 1-85912-044-X, C432), in conjunction with the Object Management Group (OMG).

COS, Volume 1

Preliminary Specification, July 1994, Common Object Services, Volume 1 (ISBN: 1-85912-482-2, P432), in conjunction with the Object Management Group (OMG).

DCE Directory

CAE Specification, December 1994, X/Open DCE: Directory Services (ISBN: 1-85912-078-4, C312).


DCE Event Management Service, OSF RFC 67.0, January 1996, R.Cohen (IBM), G Wilson (IBM), Open Software Foundation (The Open Group) Request for Comments, available from URL


CAE Specification, August 1994, X/Open DCE: Remote Procedure Call (ISBN: 1-85912-041-5, C309).

This specification is now also ISO International Standard ISO/IEC 11578:1996, Information technology - Open Systems Interconnection - Remote Procedure Call (RPC)

GSS-API Extensions

Snapshot, January 1994, Generic Security Service API (GSS-API) Security Attribute and Delegation Extensions (ISBN: 1-85912-261-1, S307).

Internationalisation Guide

Guide, July 1993, Internationalisation Guide, Version 2 (ISBN: 1-859120-02-4, G304).

ISO/IEC 10165-2
ISO/IEC 10165-2:1992(E), Information Technology - Open Systems Interconnnect - Structure of Management Information: Definition of Management Information.

ISO/IEC 10165-4
ISO/IEC 10165-4:1992(E), Information Technology - Open Systems Interconnnect - Structure of Management Information - Part 4: Guidelines for the Definition of Managed Objects.

ISO/IEC 10165-5
ISO/IEC 10165-5:1994(E), Information Technology - Open Systems Interconnnect - Structure of Management Information: Generic Management Information.

ISO/IEC 10165-6
ISO/IEC 10165-6:1994(E), Information Technology - Open Systems Interconnnect - Structure of Management Information: Requirements and Guidelines for Implementation Conformance Statement Proformas Associated with OSI Management.

ISO/IEC 10165-7
ISO/IEC 10165-7:1992(E), Information Technology - Open Systems Interconnnect - Structure of Management Information - Part 7: General Relationship Model.

ISO/IEC 10646-1
ISO/IEC 10646-1:1993(E), Information Technology - Universal Multiple-Octet Coded Character Set (UCS) - Part 1: Architecture and Basic Multilingual Plane.

OMG Security White Paper

OMG White Paper on Security. OMG Security Working Group. Issue: 1.0 April 1994.


Preliminary Specification, June 1995, Systems Management: Common Management Facilities, Volume 1 (ISBN: 1-85912-047-4, P421).

XDS, Issue 3

CAE Specification, May 1996, API to Directory Services (XDS), Issue 3 (ISBN: 1-85912-180-2, C608).


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


Preliminary Specification, March 1994, Systems Management: GDMO to XOM Translation Algorithm (ISBN: 1-85912-023-7, P319).


CAE Specification, March 1994, Systems Management: Management Protocol API (ISBN 1-85912-027-X, C306).

XOM, Issue 3

CAE Specification, May 1996, OSI-Abstract-Data Manipulation API (XOM), Issue 3 (ISBN: 1-85912-175-6, C607).

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