Overview:
The Information Systems Architecture Phase (Phase C) in TOGAF (The Open Group Architecture Framework) focuses on developing the data and application aspects of the architecture. It aims to create Target Architectures that support business processes through IT implementations.
General Approach:
- Implementation Strategies:
- Top-down and Bottom-up: A common approach involves both top-down design and bottom-up implementation.
- Data-Driven: Implementing systems that create data first, followed by those processing data and archiving data.
- Inputs:
- Request for Architecture Work
- Capability Assessment
- Communications Plan
- Organization Model for Enterprise Architecture
- Tailored Architecture Framework
- Application and Data Principles
- Statement of Architecture Work
- Architecture Vision
- Architecture Repository
- Draft Architecture Definition Document
- Baseline and Target Architectures for Business, Data, and Application
- Draft Architecture Requirements Specification
- Architecture Roadmap (business architecture focus)
Data Architecture Development:
- Selecting Reference Models, Viewpoints, and Tools:
- Review and validate data principles.
- Identify relevant resources, viewpoints, and tools.
- Develop catalogs of data building blocks, matrices, and diagrams.
- Developing Baseline Data Architecture Description:
- Provide a current outlook on the existing business environment.
- Developing Target Data Architecture Description:
- Provide a future representation of the data architecture to meet new requirements.
- Performing Gap Analysis:
- Identify gaps between baseline and target architecture.
- Resolve conflicts using trade-off analysis.
- Defining Roadmap Components:
- Aid in prioritizing activities for subsequent phases.
- Resolving Impact:
- Determine the impact of implementing the target data architecture.
- Consider ongoing enterprise operations.
- Conducting Formal Reviews:
- Ensure the target data architecture meets stakeholder requirements.
- Finalizing Data Architecture:
- Select building blocks and appropriate standards.
- Document rationale for decisions.
- Creating Architecture Definition Document:
- Document components, including business data model, logical data model, and more.
Application Architecture Development:
- Selecting Reference Models, Viewpoints, and Tools:
- Review and validate application principles.
- Identify relevant resources, viewpoints, and tools.
- Determine types of requirements to be collected.
- Identifying Overall Modeling Process:
- Develop catalogs of application building blocks, matrices, and diagrams.
- Developing Baseline Application Architecture Description:
- Provide a current outlook on the existing business environment.
- Developing Target Application Architecture Description:
- Provide a future representation of the application architecture to meet new requirements.
- Performing Gap Analysis:
- Identify gaps between baseline and target architecture.
- Resolve conflicts using trade-off analysis.
- Defining Roadmap Components:
- Aid in prioritizing activities for subsequent phases.
- Resolving Impact:
- Determine the impact of implementing the target application architecture.
- Consider ongoing enterprise operations.
- Conducting Formal Reviews:
- Ensure the target application architecture meets stakeholder requirements.
- Finalizing Application Architecture:
- Select building blocks and appropriate standards.
- Document rationale for decisions.
- Creating Architecture Definition Document:
- Document components of the application architecture.
Key Considerations:
- Building Blocks Definition:
- Define new or existing building blocks within the phase.
- Building blocks should align with the scope and goals of the overall effort.
Outputs of Information Systems Architecture:
- Refined Architecture Vision:
- Ensures alignment with the evolving business needs and goals.
- Drafted Architecture Definition Document (ADD):
- Captures the rationale for building block decisions.
- Describes various components of the data and application architectures.
- Drafted Data and Application Sections of Architecture Requirements Specification:
- Outlines specific requirements related to data and application architectures.
- Identified Information System Components in Architecture Roadmap:
- Defines components critical for the successful implementation of the architecture.
TOGAF ADM Phase Summary – Information Systems Architecture
Here’s a summarized tabular format for the steps and outputs of TOGAF ADM Phase C: Information Systems Architecture:
| Step | Data Architecture | Application Architecture |
|---|---|---|
| 1. Selecting Reference Models, Viewpoints, and Tools | Review and validate data principles. Identify relevant resources, viewpoints, and tools. Develop catalogs of data building blocks, matrices, and diagrams. | Review and validate application principles. Identify relevant resources, viewpoints, and tools. Develop catalogs of application building blocks, matrices, and diagrams. Determine types of requirements to be collected. |
| 2. Developing Baseline Architecture Description | Provide a current outlook on the existing business environment. | Provide a current outlook on the existing business environment. |
| 3. Developing Target Architecture Description | Provide a future representation of the data architecture to meet new requirements. | Provide a future representation of the application architecture to meet new requirements. |
| 4. Performing Gap Analysis | Identify gaps between baseline and target architecture. Resolve conflicts using trade-off analysis. | Identify gaps between baseline and target architecture. Resolve conflicts using trade-off analysis. |
| 5. Defining Roadmap Components | Aid in prioritizing activities for subsequent phases. | Aid in prioritizing activities for subsequent phases. |
| 6. Resolving Impact | Determine the impact of implementing the target architecture in the current environment and ongoing enterprise operations. | Determine the impact of implementing the target architecture in the current environment and ongoing enterprise operations. |
| 7. Conducting Formal Reviews | Ensure that the target architecture meets the requirements of stakeholders. | Ensure that the target architecture meets the requirements of stakeholders. |
| 8. Finalizing Architecture | Select building blocks and appropriate standards. Document rationale for decisions. | Select building blocks and appropriate standards. Document rationale for decisions. |
| 9. Creating Architecture Definition Document | Document components of the data architecture, including business data model, logical data model, etc. | Document components of the application architecture. |
| Outputs | Description |
|---|---|
| Refined Architecture Vision | Ensures alignment with evolving business needs and goals. |
| Drafted Architecture Definition Document (ADD) | Captures the rationale for building block decisions. Describes various components of data and application architectures. |
| Drafted Data and Application Sections of Architecture Requirements Specification | Outlines specific requirements related to data and application architectures. |
| Identified Information System Components in Architecture Roadmap | Defines components critical for the successful implementation of the architecture. |
Conclusion
The Information Systems Architecture Phase is crucial for shaping the data and application aspects of the overall enterprise architecture. Through systematic steps, it ensures alignment with business processes and supports IT implementations. The outputs generated serve as valuable input for subsequent phases, contributing to a well-defined and strategically aligned enterprise architecture.
Phase C provides a comprehensive approach to developing both data and application architectures, ensuring that the resulting architectures meet the needs of stakeholders, resolve conflicts, and align with the overarching business objectives. The documentation produced serves as a foundation for further refinement and implementation in subsequent phases of the TOGAF Architecture Development Method (ADM).