The architectural work products with the artITecture method are a way of documenting and communicating ‘architectural thinking’ so that others may understand why a system is architected (designed) in a particular way.
36.2.3 Architecture Definition Document
Purpose
The Architecture Definition Document is the deliverable container for the core architectural artifacts created during a project and for important related information. The Architecture Definition Document spans all architecture domains (business, data, application, and technology) and also examines all relevant states of the architecture (baseline, transition, and target).
A Transition Architecture shows the enterprise at an architecturally significant state between the Baseline and Target Architectures. Transition Architectures are used to describe transitional Target Architectures necessary for effective realization of the Target Architecture.
The Architecture Definition Document is a companion to the Architecture Requirements Specification, with a complementary objective:
The Architecture Definition Document provides a qualitative view of the solution and aims to communicate the intent of the architects. The Architecture Requirements Specification provides a quantitative view of the solution, stating measurable criteria that must be met during the implementation of the architecture.
Content
Typical contents of an Architecture Definition Document are:
Scope
Goals, objectives, and constraints
Architecture principles
Baseline Architecture
Architecture models (for each state to be modeled):
Business Architecture models
Data Architecture models
Application Architecture models
Technology Architecture models
Rationale and justification for architectural approach
Mapping to Architecture Repository:
Mapping to Architecture Landscape
Mapping to reference models
Mapping to standards
Re-use assessment
Gap analysis
Impact assessment
Transition Architecture:
Definition of transition states
Business Architecture for each transition state
Data Architecture for each transition state
Application Architecture for each transition state
Technology Architecture for each transition state