Introduction

The X/Open Systems Management Problem Statement (see reference PS) describes several aspects of the problem, and also surveys some of the existing work in this area. This document, the X/Open Systems Management Reference Model, is intended to describe a framework for providing solutions for the problem.

The Reference Model describes its various components and how they interact. It does not give detailed descriptions of individual components, but addresses their general properties and their means of interaction. The model identifies, but does not define, the required management interfaces.

Background

As enterprises take increasing advantage of networking technology by interconnecting computing equipment supplied by a variety of vendors, they are finding it both difficult and costly to administer their collective systems.

Traditional systems management technology is neither open nor integrated. Management systems from different vendors do not interoperate and there is little or no integration in the management of different, but related, areas.

A network of heterogeneous systems has either to be managed as a series of sub-groups of systems, each from a single vendor, or end-users have to provide their own integration layer that implements common functionality across the complete set of machines.

Similarly, different aspects of the users' environment, for instance their interaction with the mail and printing systems, are managed using differing interfaces.

As a result, enterprises must employ significant numbers of skilled system administrators to manage the diverse features of these systems. When seen as increased cost of ownership, high system administration costs can act as a deterrent to continued investment in open systems.

Goals and Objectives

The goals of this Reference Model include the following:

• To identify the crucial aspects of the distributed systems management problem space, especially those that are unique to this topic.

• To establish common terminology.

• To establish a problem-oriented approach to the realisation of distributed systems management solutions.

The Reference Model will describe the components and architecture necessary to build a comprehensive distributed systems management environment. It describes the environment in which distributed systems management can be performed without requiring that particular technologies be used.

Distributed systems management can be implemented using a variety of technologies. Any solution that does not implement all the concepts embodied in the Reference Model is probably deficient in some respect, and any technology that is not capable of implementing the concepts is probably unsuitable as an implementation base. The Reference Model identifies the mapping between the abstract concepts and some technologies that provide suitable implementation bases for the realisation of the Model.

It is a key objective of the X/Open Systems Management Programme to specify a systems management model that will simplify the whole area of system administration, allowing increasingly complex systems to be administered by lower numbers of less highly skilled personnel.

The model is intended to satisfy several high-level system requirements:

Portability

The ability to make software on managed and managing systems portable in source code form between different vendors' systems by extending the X/Open Common Applications Environment (CAE).

Interoperability

The ability of management systems, and components of such systems from different vendors, to interwork, thus allowing a network of heterogeneous systems to be managed as a single system.

Transparency

The ability to administer Resources without the need to be explicitly aware of their location or details of their implementation.

Extensibility

The ability to extend the scope and capabilities of the management system and to implement different management policies as required. This includes the ability to make use of new communications protocols.

Robustness

The ability of the management system to provide integrity and the necessary levels of security and reliability.

The following requirements relate to the form of the interfaces that will be provided to access the management functionality:

Ease of Use

The services and APIs should be simple to use, consistent with the complexity of the underlying functionality.

Consistency

Wherever appropriate, stylistic inconsistency should be avoided in specification of interfaces.

The management model is intended to describe the vision of the X/Open Systems Management Working Group, to provide for the distributed management of distributed systems. It is the intent of the model to allow fully transparent management, with full interoperability, such that a network of heterogeneous, conforming systems can be managed from any system on the network.

Relationship to Implementation Technologies

The Reference Model is described in abstract terms, and is intended to be realisable in a variety of technologies. In the appendices, a mapping is provided from the abstract Reference Model to selected technologies. There is currently much industry development work in the area of distributed systems management, and the mapping provided reflects the technologies that are being used.

It is anticipated that the primary vehicle for implementation of the Reference Model will be the Object Management Group's Object Request Broker (ORB) technology. At the time of writing some major issues relating to the practical implementation of ORB based management systems are still to be resolved, particularly those relating to the interoperability of different ORB implementations.

Another significant implementation technology, particularly in the area of Network management, is that embodied by the ISO/CCITT and Internet management protocols, CMIP and SNMP. The X/Open Management Protocols API (XMP) provides a uniform access method to these technologies.

OMG Mapping and ISO/CCITT and Internet Management Mapping describe how the above technologies may be mapped onto the Reference Model. However, this does not imply inherent portability or interoperability between these environments. Interoperability between OMG and XMP addresses some of the methods that are necessary when managing a hybrid environment, which includes OMG, OSI, and Internet components.

In addition to the above, which represent the anticipated future development of distributed systems management, the Reference Model can also be implemented using currently available technologies. These include those based on existing Remote Procedure Call (RPC) technologies, such as ONC NIS and DCE RPC.

Relationship to Legacy Systems

In order to fully meet the requirements to provide distributed systems management across the full range of IT systems that make up today's complex information management environments, it is also necessary to integrate the management of both open and legacy (proprietary) systems.

In this context, legacy systems are characterised by their use of management systems based on protocols and interfaces that are not conformant to open standards. The techniques that are described within the Reference Model in order to provide interoperability between the technologies that are expected to be used to implement the Reference Model may also be used to provide interoperability with legacy systems. These techniques allow legacy systems to be integrated into distributed, heterogeneous management systems, however, this integration is limited to interoperability between management systems, and will not provide for portability of management software between open and legacy systems.

Intended Audience

The Reference Model is intended for the following audience:

• Implementers of systems management frameworks

• Implementers of systems management applications

• IT strategists and decision makers

• Providers of standards and technology

• End-users responsible for the deployment of distributed systems management