Friday, May 11, 2007

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


 





  1. 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








  2. Assemble architecture team





    1. Project leader appointed by senior management




    2. Team members must be drawn from across the organization






  3. Tailor architectural principles





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





  4. Develop ADP plan





    1. Work breakdown structure




    2. Schedule




    3. Resource allocations




    4. Products and deliverables






  5. Select standards




  6. 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

 





  1. 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






  2. Characterize baseline EISA views





    1. Current business processes




    2. Current work structure




    3. Current information entities




    4. Current state of automation, including infrastructure






  3. 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






  4. 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


 





  1. 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?






  2. 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






  3. 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






  4. 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








  5. 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


 





  1. 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






  2. Assess technology maturity





    1. Levels of technology maturity: experimental, adoption/expansion,
      formalization, mature, obsolete



    2. Technology stage characteristics




    3. Technology selection




    4. COTS






  3. Identify design constraints





    1. Constraints are factors unaffected by architectural change




    2. Assess availability and feasibility of technology




    3. Assess interoperability requirements






  4. 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






  5. 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


 





  1. 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








  2. 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








  3. 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








  4. Review architecture implementation plan




 


Activity 5: Architecture development administration


 





  1. 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





  2. 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





  3. Maintain architecture development toolkit





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





  4. 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






  5. 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?





  1. Enterprise architecture guides enterprise IT planning and evolution




  2. Aligns infrastructure to support business initiatives





    1. Technology




    2. Business or functional




    3. Organizational






  3. Promotes





    1. Quality




    2. Scalability, performance




    3. Reusability, maintainability, portability




    4. Internal consistency




    5. Ease of application integration






 


An enterprise system architecture (ESA) is:





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



  2. system of information systems




  3. City Planning




 


An information system architecture (ISA) is:





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



  2. Building Planning




 


A software architecture is:





  1. a collection of software components that comprises an application




  2. 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.

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