Task: Business Architecture |
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This chapter describes the development of a Business Architecture to support an agreed Architecture Vision. |
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Purpose
The objectives of Phase B are:
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To describe the Baseline Business Architecture
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To develop a Target Business Architecture, describing the product and/or service strategy, and the organizational,
functional, process, information, and geographic aspects of the business environment, based on the business
principles, business goals, and strategic drivers
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To analyze the gaps between the Baseline and Target Business Architectures
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To select and develop the relevant architecture viewpoints that will enable the architect to demonstrate how the
stakeholder concerns are addressed in the Business Architecture
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To select the relevant tools and techniques to be used in association with the selected viewpoints
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Relationships
Inputs | Mandatory:
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Outputs |
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Main Description
Figure: Phase B: Business Architecture
Approach
General
A knowledge of the Business Architecture is a prerequisite for architecture work in any other domain (Data,
Application, Technology), and is therefore the first architecture activity that needs to be undertaken, if not catered
for already in other organizational processes (enterprise planning, strategic business planning, business process
re-engineering, etc.).
In practical terms, the Business Architecture is also often necessary as a means of demonstrating the business value of
subsequent architecture work to key stakeholders, and the return on investment to those stakeholders from supporting
and participating in the subsequent work.
The scope of the work in Phase B will depend to a large extent on the enterprise environment. In some cases, key
elements of the Business Architecture may be done in other activities; for example, the enterprise mission, vision,
strategy, and goals may be documented as part of some wider business strategy or enterprise planning activity that has
its own lifecycle within the enterprise.
In such cases, there may be a need to verify and update the currently documented business strategy and plans, and/or to
bridge between high-level business drivers, business strategy, and goals on the one hand, and the specific business
requirements that are relevant to this architecture development effort. The business strategy typically defines what to
achieve - the goals and drivers, and the metrics for success - but not how to get there. That is role of the Business
Architecture.
In other cases, little or no Business Architecture work may have been done to date. In such cases, there will be a need
for the architecture team to research, verify, and gain buy-in to the key business objectives and processes that the
architecture is to support. This may be done as a free-standing exercise, either preceding architecture development, or
as part of Phase A.
In both of these cases, the business scenario technique (see Part III,
Business Scenarios) of the TOGAF ADM, or any other method that illuminates the key business requirements and
indicates the implied technical requirements for IT architecture, may be used.
A key objective is to re-use existing material as much as possible. In architecturally more mature environments, there
will be existing Architecture Definitions, which (hopefully) will have been maintained since the last architecture
development cycle. Where architecture descriptions exist, these can be used as a starting point, and verified and
updated if necessary; see Part V, Architecture Continuum .
Gather and analyze only that information that allows informed decisions to be made relevant to the scope of this
architecture effort. If this effort is focused on the definition of (possibly new) business processes, then Phase B
will necessarily involve a lot of detailed work. If the focus is more on the Target Architectures in other domains
(data/information, application systems, infrastructure) to support an essentially existing Business Architecture, then
it is important to build a complete picture in Phase B without going into unnecessary detail.
Developing the Baseline Description
If an enterprise has existing architecture descriptions, they should be used as the basis for the Baseline Description.
This input may have been used already in Phase A in developing an Architecture Vision, and may even be sufficient in
itself for the Baseline Description.
Where no such descriptions exist, information will have to be gathered in whatever format comes to hand.
The normal approach to Target Architecture development is top-down. In the Baseline Description, however, the analysis
of the current state often has to be done bottom-up, particularly where little or no architecture assets exist. In such
a case, the architect simply has to document the working assumptions about high-level architectures, and the process is
one of gathering evidence to turn the working assumptions into fact, until the law of diminishing returns sets in.
Business processes that are not to be carried forward have no intrinsic value. However, when developing Baseline
Descriptions in other architecture domains, architectural components (principles, models, standards, and current
inventory) that are not to be carried forward may still have an intrinsic value, and an inventory may be needed in
order to understand the residual value (if any) of those components.
Whatever the approach, the goal should be to re-use existing material as much as possible, and to gather and analyze
only that information that allows informed decisions to be made regarding the Target Business Architecture. It is
important to build a complete picture without going into unnecessary detail.
Business Modeling
Business models should be logical extensions of the business scenarios from the Architecture Vision, so that the
architecture can be mapped from the high-level business requirements down to the more detailed ones.
A variety of modeling tools and techniques may be employed, if deemed appropriate (bearing in mind the above caution
not to go into unnecessary detail). For example:
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Activity Models (also called Business Process Models) describe the functions associated with the
enterprise's business activities, the data and/or information exchanged between activities (internal exchanges),
and the data and/or information exchanged with other activities that are outside the scope of the model (external
exchanges). Activity models are hierarchical in nature. They capture the activities performed in a business
process, and the ICOMs (inputs, controls, outputs, and mechanisms/resources used) of those activities. Activity
models can be annotated with explicit statements of business rules, which represent relationships among the ICOMs.
For example, a business rule can specify who can do what under specified conditions, the combination of inputs and
controls needed, and the resulting outputs. One technique for creating activity models is the IDEF (Integrated
Computer Aided Manufacturing (ICAM) DEFinition) modeling technique.
The Object Management Group (OMG) has developed the Business Process Modeling Notation (BPMN), a standard for
business process modeling that includes a language with which to specify business processes, their tasks/steps,
and the documents produced.
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Use-Case Models can describe either business processes or systems functions, depending on the focus of the
modeling effort. A use-case model describes the business processes of an enterprise in terms of use-cases and
actors corresponding to business processes and organizational participants (people, organizations, etc.). The
use-case model is described in use-case diagrams and use-case specifications.
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Class Models are similar to logical data models. A class model describes static information and
relationships between information. A class model also describes informational behaviors. Like many of the other
models, it can also be used to model various levels of granularity. Depending on the intent of the model, a class
model can represent business domain entities or systems implementation classes. A business domain model represents
key business information (domain classes), their characteristics (attributes), their behaviors (methods or
operations), and relationships (often referred to as multiplicity, describing how many classes typically
participate in the relationship), and cardinality (describes required or optional participation in the
relationship). Specifications further elaborate and detail information that cannot be represented in the class
diagram.
Figure: UML Business Class Diagram
All three types of model above can be represented in the Unified Modeling Language (UML), and a variety of tools exist
for generating such models.
Certain industry sectors have modeling techniques specific to the sector concerned. For example, the Defense sector
uses the following models. These models have to be used carefully, especially if the location and conduct of business
processes will be altered in the visionary Business Architecture.
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The Node Connectivity Diagram describes the business locations (nodes), the "needlines" between them, and
the characteristics of the information exchanged. Node connectivity can be described at three levels: conceptual,
logical, and physical. Each needline indicates the need for some kind of information transfer between the two
connected nodes. A node can represent a role (e.g., a CIO), an organizational unit, a business location or
facility, and so on. An arrow indicating the direction of information flow is annotated to describe the
characteristics of the data or information - for example, its content, media, security or classification level,
timeliness, and requirements for information system interoperability.
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The Information Exchange Matrix documents the information exchange requirements for an enterprise
architecture. Information exchange requirements express the relationships across three basic entities (activities,
business nodes and their elements, and information flow), and focus on characteristics of the information exchange,
such as performance and security. They identify who exchanges what information with whom, why the information is
necessary, and in what manner.
Although originally developed for use in the Defense sector, these models are finding increasing use in other sectors
of government, and may also be considered for use in non-government environments.
Architecture Repository
As part of Phase B, the architecture team will need to consider what relevant Business Architecture resources are
available from the Architecture Repository (see Part V, Architecture Repository), in particular:
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Generic business models relevant to the organization's industry sector. These are "Industry Architectures", in
terms of the Enterprise Continuum. They are held in the Reference Library of the Architecture Repository (see Part V, Reference Library). For example:
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The Object Management Group (OMG) - www.omg.org - has a number of vertical Domain Task Forces developing
business models relevant to specific vertical domains such as Healthcare, Transportation, Finance, etc.
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The TeleManagement Forum (TMF) - www.tmforum.org - has developed detailed business models relevant to the
Telecommunications industry.
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Government departments and agencies in different countries have reference models and frameworks mandated
for use, intended to promote cross-departmental integration and interoperability. An example is the Federal
Enterprise Architecture Business Reference Model, which is a function-driven framework for describing the
business operations of the Federal Government independent of the agencies that perform them.
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Business models relevant to common high-level business domains - such as electronic commerce, supply chain
management, etc. - that are published within the IT industry. (These are "Common Systems Architectures", in terms
of the Enterprise Continuum.) For example:
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The Resource-Event-Agent (REA) business model was originally created by William E. McCarthy (refer to www.msu.edu/user/mccarth4)
of Michigan State University, mainly for modeling of accounting systems. It has proved so useful for better
understanding of business processes that it has become one of the major modeling frameworks for both
traditional enterprises and e-Commerce systems. In particular, it has been extended by Robert Haugen and
McCarthy for supply chain management (refer to www.jeffsutherland.org/oopsla2000/mccarthy/mccarthy.htm).
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The STEP Framework (STandard for the Exchange of Product model data) is concerned with product design and
supply chain interworking. STEP is an ISO standard (ISO 10303). Implementation of the STEP standard has
been led by some large aerospace manufacturers, and has also been taken up in other industries that have a
need for complex graphic and process data, such as the construction industry.
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The Open Applications Group (OAG) - www.openapplications.org - is focused on defining a framework for allowing
heterogeneous business applications to communicate together. Its OAGIS integration model and specification
address the needs of traditional Enterprise Resource Planning (ERP) integration, as well as supply chain
management and electronic commerce.
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RosettaNet - www.rosettanet.org - is a consortium created by leading companies in the
computer, electronic component, and semiconductor manufacturing supply chains. Its mission is to develop a
complete set of standard e-Business processes for these supply chains, and to promote and support their
adoption and use.
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Enterprise-specific building blocks (process components, business rules, job descriptions, etc.).
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Applicable standards.
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Steps
Select Reference Models, Viewpoints, and Tools
Select relevant Business Architecture resources (reference models, patterns, etc.) from the Architecture Repository, on
the basis of the business drivers, and the stakeholders and concerns.
Select relevant Business Architecture viewpoints (e.g., operations, management, financial); i.e., those that will
enable the architect to demonstrate how the stakeholder concerns are being addressed in the Business Architecture.
Identify appropriate tools and techniques to be used for capture, modeling, and analysis, in association with the
selected viewpoints. Depending on the degree of sophistication warranted, these may comprise simple documents or
spreadsheets, or more sophisticated modeling tools and techniques, such as activity models, business process models,
use-case models, etc.
Determine Overall Modeling Process
For each viewpoint, select the models needed to support the specific view required, using the selected tool or method.
Ensure that all stakeholder concerns are covered. If they are not, create new models to address concerns not covered,
or augment existing models. Business scenarios are a useful technique to discover and document business requirements,
and may be used iteratively, at different levels of detail in the hierarchical decomposition of the Business
Architecture. Business scenarios are described in Part III,
Business Scenarios.
Activity models, use-case models, and class models are mentioned earlier as techniques to enable the definition of an
organization's business architecture. In many cases, all three approaches can be utilized in sequence to progressively
decompose a business.
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Structured Analysis: Identifies the key business functions within the scope of the architecture, and maps
those functions onto the organizational units within the business.
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Use-case Analysis: The breakdown of business-level functions across actors and organizations allows the
actors in a function to be identified and permits a breakdown into services supporting/delivering that functional
capability.
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Process Modeling: The breakdown of a function or business service through process modeling allows the
elements of the process to be identified, and permits the identification of lower-level business services or
functions.
The level and rigor of decomposition needed varies from enterprise to enterprise, as well as within an enterprise, and
the architect should consider the enterprise's goals, objectives, scope, and purpose of the enterprise architecture
effort to determine the level of decomposition.
Identify Required Service Granularity Level, Boundaries, and
Contracts
The TOGAF content framework differentiates between the functions of a business and the services of a business. Business
services are specific functions that have explicit, defined boundaries that are explicitly governed. In order to allow
the architect flexibility to define business services at a level of granularity that is appropriate for and manageable
by the business, the functions are split as follows: micro-level functions will have explicit, defined boundaries, but
may not be explicitly governed. Likewise, macro business functions may be explicitly governed, but may not have
explicit, defined boundaries.
The Business Architecture phase therefore needs to identify which components of the architecture are functions and
which are services. Services are distinguished from functions through the explicit definition of a service contract.
When Baseline Architectures are being developed, it may be the case that explicit contracts do not exist and it would
therefore be at the discretion of the architect to determine whether there is merit in developing such contracts before
examining any Target Architectures.
A service contract covers the business/functional interface and also the technology/data interface. Business
Architecture will define the service contract at the business/functional level, which will be expanded on in the
Application and Technology Architecture phases.
The granularity of business services should be determined according to the business drivers, goals, objectives, and
measures for this area of the business. Finer-grained services permit closer management and measurement (and can be
combined to create coarser-grained services), but require greater effort to govern. Guidelines for identification of
services and definition of their contracts can be found in Part III, Using TOGAF to Define & Govern SOAs.
Identify Required Catalogs of Business Building Blocks
Catalogs capture inventories of the core assets of the business. Catalogs are hierarchical in nature and capture the
decomposition of a building block and also decompositions across related building blocks (e.g., organization/actor).
Catalogs form the raw material for development of matrices and views and also act as a key resource for portfolio
managing business and IT capability.
The following catalogs should be considered for development within a Business Architecture:
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Organization/Actor catalog
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Driver/Goal/Objective catalog
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Role catalog
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Business Service/Function catalog
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Location catalog
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Process/Event/Control/Product catalog
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Contract/Measure catalog
The structure of catalogs is based on the attributes of metamodel entities, as defined in Part IV, Content Metamodel.
Identify Required Matrices
Matrices show the core relationships between related model entities.
Matrices form the raw material for development of views and also act as a key resource for impact assessment, carried
out as a part of gap analysis.
The following matrices should be considered for development within a Business Architecture:
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Business interaction matrix (showing dependency and communication between organizations and actors)
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Actor/role matrix (showing the roles undertaken by each actor)
The structure of matrices is based on the attributes of metamodel entities, as defined in Part IV, Content Metamodel.
Identify Required Diagrams
Diagrams present the Business Architecture information from a set of different perspectives (viewpoints) according to
the requirements of the stakeholders.
The following Diagrams should be considered for development within a Business Architecture:
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Business Footprint diagram
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Business Service/Information diagram
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Functional Decomposition diagram
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Goal/Objective/Service diagram
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Use-case diagram
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Organization Decomposition diagram
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Process Flow diagram
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Events diagram
The structure of diagrams is based on the attributes of metamodel entities, as defined in Part IV, Content Metamodel.
Identify Types of Requirement to be Collected
Once the Business Architecture catalogs, matrices, and diagrams have been developed, architecture modeling is completed
by formalizing the business-focused requirements for implementing the Target Architecture. These requirements may
relate to the business domain, or may provide requirements input into the Data, Application, and Technology
Architectures.
Within this step, the architect should identify types of requirement that must be met by the architecture
implementation, including:
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Functional requirements
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Non-functional requirements
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Assumptions
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Constraints
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Domain-specific Business Architecture principles
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Policies
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Standards
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Guidelines
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Specifications
In many cases, the Architecture Definition will not be intended to give detailed or comprehensive requirements for a
solution (as these can be better addressed through general requirements management discipline). The expected coverage
of requirements content should be established during the Architecture Vision phase.
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Develop Baseline Business Architecture Description
Develop a Baseline Description of the existing Business Architecture, to the extent necessary to support the Target
Business Architecture. The scope and level of detail to be defined will depend on the extent to which existing business
elements are likely to be carried over into the Target Business Architecture, and on whether architecture descriptions
exist, as described in Approach. To the extent possible, identify the relevant Business Architecture
building blocks, drawing on the Architecture Repository.
Where new architecture models need to be developed to satisfy stakeholder concerns, use the models identified within
Step 1 as a guideline for creating new architecture content to describe the Baseline Architecture.
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Develop Target Business Architecture Description
Develop a Target Description for the Business Architecture, to the extent necessary to support the Architecture Vision.
The scope and level of detail to be defined will depend on the relevance of the business elements to attaining the
Target Architecture Vision, and on whether architectural descriptions exist. To the extent possible, identify the
relevant Business Architecture building blocks, drawing on the Architecture Repository.
Where new architecture models need to be developed to satisfy stakeholder concerns, use the models identified within
Step 1 as a guideline for creating new architecture content to describe the Target Architecture.
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Perform Gap Analysis
First, verify the architecture models for internal consistency and accuracy:
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Perform trade-off analysis to resolve conflicts (if any) among the different views
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Validate that the models support the principles, objectives, and constraints
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Note changes to the viewpoint represented in the selected models from the Architecture Repository, and document
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Test architecture models for completeness against requirements
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Identify gaps between the baseline and target:
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Create gap matrix, as described in Part
III, Gap Analysis
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Identify building blocks to be carried over, classifying as either changed or unchanged
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Identify eliminated building blocks
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Identify new building blocks
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Identify gaps and classify as those that should be developed and those that should be procured
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Define Roadmap Components
Following creation of a Baseline Architecture, Target Architecture, and gap analysis results, a business roadmap is
required to prioritize activities over the coming phases.
This initial Business Architecture roadmap will be used as raw material to support more detailed definition of a
consolidated, cross-discipline roadmap within the Opportunities & Solutions phase.
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Resolve Impacts Across the Architecture Landscape
Once the Business Architecture is finalized, it is necessary to understand any wider impacts or implications.
At this stage, other architecture artifacts in the Architecture Landscape should be examined to identify:
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Does this Business Architecture create an impact on any pre-existing architectures?
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Have recent changes been made that impact on the Business Architecture?
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Are there any opportunities to leverage work from this Business Architecture in other areas of the organization?
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Does this Business Architecture impact other projects (including those planned as well as those currently in
progress)?
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Will this Business Architecture be impacted by other projects (including those planned as well as those currently
in progress)?
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Conduct Formal Stakeholder Review
Check the original motivation for the architecture project and the Statement of Architecture Work against the proposed
Business Architecture, asking if it is fit for the purpose of supporting subsequent work in the other architecture domains.
Refine the proposed Business Architecture only if necessary. |
Finalize the Business Architecture
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Select standards for each of the building blocks, re-using as much as possible from the reference models selected
from the Architecture Repository
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Fully document each building block
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Conduct final cross-check of overall architecture against business goals; document rationale for building block
decisions in the architecture document
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Document final requirements traceability report
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Document final mapping of the architecture within the Architecture Repository; from the selected building blocks,
identify those that might be re-used (working practices, roles, business relationships, job descriptions, etc.),
and publish via the Architecture Repository
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Finalize all the work products, such as gap analysis results
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Create Architecture Definition Document
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Document rationale for building block decisions in the Architecture Definition Document
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Prepare the business sections of the Architecture Definition Document, comprising some or all of:
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A business footprint (a high-level description of the people and locations involved with key business
functions)
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A detailed description of business functions and their information needs
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A management footprint (showing span of control and accountability)
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Standards, rules, and guidelines showing working practices, legislation, financial measures, etc.
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A skills matrix and set of job descriptions
If appropriate, use reports and/or graphics generated by modeling tools to demonstrate key views of the architecture.
Route the document for review by relevant stakeholders, and incorporate feedback.
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More Information
Guidelines |
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Supporting Materials |
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The Open Group gratefully acknowledge Capgemini for the creation of the Eclipse Process Framework Method Plugin for
TOGAF9.
Downloads of the TOGAF documentation, are available under license from the TOGAF information web site. The license is
free to any organization wishing to use TOGAF entirely for internal purposes (for example, to develop an information
system architecture for use within that organization). A book is also available (in hardcopy and pdf) from The Open
Group Bookstore as document G091.
Copyright © 1999-2009 The Open Group, All Rights Reserved
TOGAF is a trademark of The Open Group.
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