TC's Blog: I Have Mastered the TISAF

Or at least I have learned how it works. TISAF stands for Treasury Information System Architecture Framework, which was recently replaced by the Treasury Enterprise Architecture Framework or TEAF. We have spent the entire semester on it in my Enterprise Architecture class, which is definitely one of a few essential ones that I need for my IT career. Dr. Frank Armour teaches the course, and I'd highly recommend it.

Here are some of the notes that I used to study for the final exam.

Activity 0: Initiate architecture development process

Define scope and objectives
1. Need a clearly defined charter
2. Activities
  1. Gather background material
  2. Develop preliminary business vision
  3. Test reaction to preliminary business vision

Assemble architecture team
1. Project leader appointed by senior management
2. Team members must be drawn from across the organization

Tailor architectural principles
1. Define or tailor the architectural principles that will guide the
  development of a target architecture

Develop ADP plan
1. Work breakdown structure
2. Schedule
3. Resource allocations
4. Products and deliverables

Select standards

Obtain senior management approval
1. Senior management
  1. Approves the project plan
  2. Provides the funding
  3. Allocates other resources
  4. Reviews progress on a periodic basis
  5. Eventually certifies the system for operational use upon
    successful completion of acceptance testing

Activity 1: Characterize the baseline architecture

Characterize enterprise business view
1. Mission statements of organization units
2. Organization chart or wiring diagram
3. Strategic plans
4. Gather documentation about existing systems
5. Identify personnel with in-depth knowledge about business practices,
  applications, databases
6. Do quickly and refine later

Characterize baseline EISA views
1. Current business processes
2. Current work structure
3. Current information entities
4. Current state of automation, including infrastructure

Characterize baseline infrastructure
1. Identify data stores and computer systems available
2. Identify current level of computer support of applications
3. Assess strengths and weaknesses of current computer systems
4. Identify networking infrastructure and topology

Create and update baseline architecture document
1. Describe current IT support to the organization
2. Enhancements
  1. Conduct user surveys
  2. Review problem area reports
  3. Look for patterns as possible indicators of focus in developing
    the target architecture

Activity 2: Target architecture development

Define/update business requirements
1. What are the strategic business objectives of the organization?
2. What data/information is needed to support the business
3. Are the applications to provide that data/information in place?

Define/update enterprise business model
1. Define the enterprise's organizational units
2. Define business locations
3. Relate business locations to the organizational units
4. Identify organizational scope, responsibilities, objectives
5. Match objectives to organizational units

Define/update target architecture views
1. Update the views from the baseline architecture
  1. Add new organization units and business locations
  2. Add new functions
  3. Add new information entities
2. Old information is needed through the architecture transition planning
  stage
3. Defining work architecture
4. Defining information architecture
5. Defining functional architecture
6. Defining infrastructure architecture

Define/update target architecture infrastructure
1. Describe the information systems that comprise the target
  infrastructure
2. Specifying technology
  1. Map business functions to communications needs
  2. Map business needs to hardware and software platforms
  3. Map business needs to software technology
3. System architecting tools
  1. Analytical models
  2. Simulation
  3. Prototyping

Create/update target architecture description
1. Assemble the results from the previous activities to create the target
  architecture description
2. Usually evolves from the previous baseline architecture description

Activity 3: Architecture transition plan

Analyze baseline/target architecture differences
1. Identify differences according to four architectural views
2. Enumerate the subsystems/components that need to be changed
3. Assess the status of legacy systems

Assess technology maturity
1. Levels of technology maturity: experimental, adoption/expansion,
  formalization, mature, obsolete
2. Technology stage characteristics
3. Technology selection
4. COTS

Identify design constraints
1. Constraints are factors unaffected by architectural change
2. Assess availability and feasibility of technology
3. Assess interoperability requirements

Select transition/migration opportunities
1. Identify critical differences
2. Develop requirements/constraints mapping
3. Perform feasibility analysis/resolve design issues
4. Analyze and assess risks
5. Identify Quick Hit opportunities
6. Describe candidate information systems

Define architecture transition plan
1. Milestones and activities
2. Includes transient systems
3. Must be performed to develop the target architecture from existing
  baseline architecture
4. Focus on dependencies among activities in this step

Activity 4: Architecture implementation plan

Define/update program management plan
1. Activities and milestones
2. Budget
3. Schedule
4. Personnel
5. Technology (tools and utilities)
6. Usually requires multiple iterations to balance resources
  1. Tradeoffs between budget and schedule
  2. Access to tools and training for personnel

Specify information system(s) development
1. Each new or modified information system should be described
2. Briefly describe changes to procedures, data, functionality, or
  infrastructure
3. Identify changes to interfaces and effects on other internal and
  external systems
4. Provide rationale for the change or modification
5. Factors to consider
  1. Development cycle times are shrinking
  2. Many business operations require shorter development cycle times
  3. Change infrastructure to facilitate rapid change
  4. Business process drives technical architectures
  5. Infrastructure must be extensible and scalable

Define/update architecture implementation plan
1. Combine resource estimates, system interdependencies, and system
  development cost estimates to produce an implementation schedule
2. Identify the specific system releases (correlated with the
  milestones), the start and end dates for specific activities, the
  elapsed time, and effort required to develop and deliver each
  information system
3. Allows the architecture development team to:
  1. Analyze resource usage
  2. Identify conflicts in personnel, facilities, and individual
    information system schedules
  3. Plan for remedial action

Review architecture implementation plan

Activity 5: Architecture development administration

Establish an architecture working group
1. Overseeing the development and maintenance of the architecture
  development process
2. Maintaining the baseline and target architectures and supporting
  documents
3. Documenting and publicizing architectural decisions
4. Maintaining current awareness of external standards issues appropriate
  to the organization

Maintain personnel skills
1. Must plan for the acquisition and/or retention of qualified, skilled
  personnel and their training in the following categories:
  architecture, hardware and software, system engineering, design and
  integration, user interface, quality assurance

Maintain architecture development toolkit
1. Provides a set of tools for supporting the architecture development
  process

Maintain architecture development library
1. Documents should be cataloged and filed in a central location for
  continuing and future reference
2. Should be maintained through addition of new and/or updated documents

Define critical success factors
1. Measurement of important business activities and information systems
  services are conducted prior to and after initial investments are made
2. Establish and maintain information resource measurement capabilities
3. Periodically review EITA usage patterns (as part of planning for next
  iteration)

Extra Notes:

Why do enterprise architecting?

Enterprise architecture guides enterprise IT planning and evolution

Aligns infrastructure to support business initiatives
1. Technology
2. Business or functional
3. Organizational

Promotes
1. Quality
2. Scalability, performance
3. Reusability, maintainability, portability
4. Internal consistency
5. Ease of application integration

An enterprise system architecture (ESA) is:

an IT architecture whose scope encompasses all of the computing of an
enterprise

system of information systems

City Planning

An information system architecture (ISA) is:

a collection of hardware, software, and telecommunication elements that
comprises an information system

Building Planning

A software architecture is:

a collection of software components that comprises an application

Floor Layout

An IT architecture framework is a conceptual model for developing an
enterprise IT architecture. It consists of models, principles, services,
approaches, standards, services, design concepts, and views that guide the
creation of specific architectures. It defines the entire domain of an IT
architecture, and provides high-level guidance for how to complete the
framework, but does not provide the exact methodologies. It provides a
holistic view a framework embraces non-technical issues. It targets senior
managers, technologists and executives responsible for making decisions.

Friday, May 11, 2007

I Have Mastered the TISAF

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