This architecture provides the common model required for interoperable
network management. It is presented as a number of viewpoints, each of
which provides a different abstraction of the system and examines some
aspects of the general model presented above. Each viewpoint describes the
major components and the interactions from different points of abstraction.
Viewpoints are simply different views of the same overall problem, with a
focus on a particular aspect. This very much follows on from the model
we presented in the Preface and chapter one.
The presentation of architectural issues through a number of viewpoints is
intended to give a clearer understanding of the issues and how they relate to
each other. This approach also helps in placing priorities on issues and
identifying areas of neglect. Considering each of the viewpoints in turn
may be helpful in the process of designing a management solution.
The three viewpoints in this architecture are as follows:
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The Enterprise Viewpoint
This viewpoint focuses on requirements of management and manageability,
policies and interoperability. The intent is to represent the user's view of
the architecture, and the overall goals of the architecture. An enterprise
model describes the overall objectives of a system in terms of roles ( for
people ), actions, goals and policies. It specifies the activities that take
place within the organization using the system, the roles that people play in
the
organization, and the interactions between the organization, the system and
the environment in which system and organization area placed.
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The Information and Computational Viewpoint
The purpose of the information viewpoint is the identification and location
of information, and the description of information processing activities.An
information model describes the structure, flow, interpretation, value
timeliness and consistency of information held within the system.
The purpose of the computational viewpoint is to describe the system as a
set of linked applications programs. A computational model provides
programmers with a description of a system that explains how distributed
application programs may be written for it.
The information and computational viewpoint compose of
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The Single Managed Object View
A managed object is the view of a resource for the purposes of management.
This view examines the characteristics of a single managed object in
isolation.
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The Managed Object Relationships View
Managed objects participate in a number of relationships. This viewpoint
describes various relationships between managed objects.
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The Logical Distribution View
Managed objects and OSs which manage them are distributed about the
network. This view discusses aspects of this distribution, and how knowledge
of that distribution is managed.
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The Engineering Viewpoint
The purpose of the engineering viewpoint is to describe the system in such a
way that designers can reason about the performance of the system built to
their designs.
This viewpoint discusses the realization of the common model as physical
communication, and addresses the requirements that arise from physically
separating OSs and managed objects. This includes communication
techniques, conformance, and supplier-specific extensions.
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Conformance
It is envisaged for a system to conform in any number of viewpoint and
conformance to each viewpoint brings different benefits.
The enterprise and information viewpoints can be used to establish a design
model of information sources and processes that meet the requirements of the
enterprise that requested the system. Conformance requirements in these
viewpoint identify constraints on the conceptual schema of the system
information base and on system management policies necessary to enable the
system to operate.
The computational viewpoint can be used to transform an information model
into a network of interacting computer programs. Conformance requirements at
this level identify constraints on programming language structures to enable
the system to operate.
The engineering viewpoint can be used to transform a computational
viewpoint model into a model in terms of processing, memory and
communication functions. The conformance requirements at this level identify
constraints on system that independently conform to the architecture
necessary to enable their interconnection.