Introduction

Scope and Purpose

Over the last few years the information technology industry has been rapidly developing object-oriented software development environments (languages, library tools, databases, etc.) for the realisation of object-oriented designs in computer systems. It is therefore natural for implementors of OSI management to expect to use these environments in the development of OSI-conformant network-management products. The fundamental enabling factor in realising this expectation is the compatibility of the underlying object models, so an evaluation of the OSI Management Model with those used in software development environments is required.

Such a comparison begs the question of which model the OSI Management Model should be compared against. In particular, the following have identified user needs for comparison:

• The Object Management Group (OMG), since it has forged an industry consensus in this respect, offers an important candidate.

• Another ISO/CCITT effort - Open Distributed Processing (ODP) - has wider scope than OMG, but provides a reference model and framework to assist comparisons of OMG and OSI management. There are expectations that most, if not all, of OMG will find its way into ODP related standards in the near future.

With regard to OMG, comparisons to the following have been developed:

ODP

in that OMG can be placed into the scope of the ODP reference model so that standardisation efforts involving OMG can be best directed.

Internet Management

in that OMG tools might be used to implement managers of embedded SNMP agents.

This Object Model Comparison report sets out to compare the three object models developed by:

• ISO/CCITT OSI management (SMI, CMIP)

• OMG CORBA for object-oriented software development (CORBA)

• Internet Management (SNMP).

Internet Management is included in the comparison, but the analysis in this report concentrates on comparing OSI management and OMG CORBA.

The definitions in this document make reference to concepts defined in the ISO/CCITT ODP reference model (see references ODP93-2 and ODP93-3). This aids efforts to relate the three object models, using concepts from the ODP perspective.

The following comparison is, in itself, a necessary stage leading towards the larger objective to capitalise on the synergistic aspects of the three models, the synergistic aspects of the work that went into their respective development, and the maximum possible synergistic goals of the three groups. As will be shown, there is overwhelming agreement between OSI management and OMG models, but there are also a number of significant differences. Some are complementary and some are conflicting. Further JIDM documents are planned which will describe approaches for reconciling these differences.

The objective of this report is to provide a comparison of the three models by documenting the similarities, the complementary differences, and the conflicting differences;

Some knowledge of the OSI Management and OMG models is assumed. Readers are referred to the referenced documents SMI, CMIP and OOM for further information on the respective models.

Document Structure

• Comparison of Object Models provides a detailed comparison of the object models.

• Summary of Similarities and Differences provides a summary of the similarities and differences.

• Reconciling the Models briefly outlines the scope of work being undertaken to reconcile the models.

• Conclusions offers some concluding remarks.