Reference Models
مدل های مرجع معماری
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Table of Content
What is a reference model? (10%) Two reference model samples
OASIS SOA (10%) OSI reference model (3%)
FEA reference model consisting of : Performance RM (16%) Business RM (13%) Service RM (10%) Technical RM (10%) Data RM (10% )
Relating FEA reference models to each other (10%)
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What is a reference model?
A reference model is an abstract framework for understanding significant relationships among the entities of some environment.
Reference model consists of a minimal set of unifying concepts, principals and relationships within a particular problem domain, and is independent of specific standards, technologies, implementations, or other concrete details.
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An abstraction hierarchy
Reference Model
Reference Architecture
Concrete (actual) Architecture
Alignment to specific
requirements
Conceptualization
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An example on this abstraction hierarchy : providing housing
Reference Model Concepts : eating area, hygiene area, sleeping area Relationships: physical separation between eating
area and hygiene area Reference Architecture
Bedroom , kitchen , WC , hallway There may be several reference architectures for one
reference models e.g. reference architecture for an apartment , hotel rooms , a space station , …
Concrete (actual) Architecture Blueprints for a specific house: where to put windows ,
their size, …
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OASIS SOA : a reference model for SOA architectures
Goal : to define the essence of service oriented architecture, and emerge with a vocabulary and a common understanding of SOA.
A basic definition of SOA : Service Oriented Architecture (SOA) is a
paradigm for organizing and utilizing distributed capabilities that may be under the control of different ownership domains.
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OASIS SOA Reference Model Main Concepts
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OASIS SOA Reference Model Relationships
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OSI Reference Model
a layered abstract description for communications and computer network protocol design.
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FEA reference models
The Federal Enterprise Architecture is an initiative of the Office of Management and Budget that aims to comply with the Clinger-Cohen Act and provide a common methodology for information technology (IT) acquisition in the United States federal government.
Goals: ease sharing of information and resources across
federal agencies reduce costs improve citizen services
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Performance reference Model
a standardized framework to measure the performance of major IT investments and their contribution to program performance
Goals: improve strategic and daily
decision-making Improve the alignment of
inputs to outputs and outcomes
Identify performance improvement opportunities
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PRM (cont ‘d)
Six Measurement Areas
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PRM (cont ‘d)
Measurement Areas Measurement Categories:
Collections within each measurement area describing the attribute or characteristic to be measured
Measurement Groupings: Further refinement of categories into specific types of
measurement indicators Measurement Indicators:
The specific measures, e.g., number and/or percentage of customers satisfied
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PRM (cont ‘d)
Mission and Business Results MA Identifies the extent to which those purposes are being
achieved. Customer Results MA
captures how well an agency or specific process within an agency is serving its customers—and ultimately citizens.
Processes and Activities MA captures key aspects of processes or activities required to
be monitored and/or improved. Technology MA
captures key elements of performance directly relating to the IT initiative
Human Capital MA : under construction! Other Fixed Assets MA : under construction!
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PRM (cont ‘d) – A piece of PRM table
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Business Reference Model
Hierarchical construct Describing day-to-day
business operations of the Federal government
function-driven independent of the agencies
that perform them
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BRM (cont ‘d)
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BRM (cont ‘d)
Services for citizens: high-level categories relating to the purpose of
government Mode of Delivery
the mechanisms the government uses to achieve its purpose
Support Delivery of Services The support functions necessary to conduct
government operations Management of Government Resources
the resource management functions that support all areas of the government’s business
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BRM (cont ‘d) – sample piece of the hierarchy
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Service Reference Model
a business and performance-driven, functional framework that classifies Service Components with respect to how they support business and/or performance objectives.
The model aids in recommending service capabilities to support the reuse of business components and services across the federal government.
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SRM (cont ‘d)
Service Domain provide a high-level view of the services and
capabilities that support enterprise and organizational processes and applications
differentiated by their business-oriented capability Service Type
further categorize and define the capabilities of each Domain
Component provide the “building blocks’ to deliver the Component
capability to the business a self contained business process or service with
predetermined functionality that may be exposed through a business or technology interface.
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SRM (cont ‘d)
Customer Preferences Grouping shown below as an example
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Technical Reference Model
a component-driven, technical framework
used to categorize the standards, specifications, and technologies that support and enable the delivery of service components and capabilities.
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TRM (cont ‘d)
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DRM intended to promote the common
identification, use, and appropriate sharing of data/information across the federal government through its standardization of data in the following three areas: Data Context : define a standard approach
for agencies to categorize their data , enable the business context of data to be well understood
Subject Area Super Type
Data Sharing : define a standard message structure known as Information Exchange Package
Data description : define a standard approach to describing an agency ‘s data
Data Object Data Property Data Representation
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An example
An organization within the federal government provides services which contribute to the health of citizens Business Area = Services for Citizens LoB (Line of Business) = Health
Subject Area = Health Super Type = immunization Data Object = vaccine Data Property = type , weight , etc Data Representation = plain text
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How DRM is used to enable collaboration
Organization A uses the DRM to categorize its data (using the BRM) into a business context.
Organization B identifies Organization A’s available data through its business context.
Organization A uses the DRM to publish the detailed structure of the actual data element (in support of the business context).
Organizations A and B determine if, in fact, the data produced by Organization A will meet the needs of Organization B.
Once Organizations A and B determine that the data can be re-used, the information exchange package is used to transmit the data.
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A reference Model for FEA Reference Model! (relationships between XRMs) The LoB represents organizations that have a
common business or program interest. Subject Area = LoB from BRM Super Type = Sub-function of LoB from BRM In PRM:
MA
LoB LoB LoB
sub-functionsub-function
Measurement Grouping
Measurement Category
Measurement Area
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A reference Model for FEA Reference Model! (relationships between XRMs)(cont)
TRM provides a framework for categorizing those technologies and standards that can be used to exchange and deliver service components (from SRM)
DRM provides for a specific type of SOA in which there is no action , only exchange of information. Considering OASIS SOA : Information model is expressed using DRM There exists no behavior model
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A reference Model for FEA Reference Model! (relationships between XRMs)(cont)
PRM
BRM
DRM
TRM
SOA
SRM