Activity: Define a Candidate Architecture

This activity creates an initial sketch of the software architecture.

Description	Work Breakdown Structure	Team Allocation	Work Product Usage

Relationships

Parent Activities	Analysis & Design

Description

This activity has the following goals:

Create an initial sketch of the architecture of the system
- Define an initial set of architecturally significant elements to use as the basis for analysis
- Define an initial set of analysis mechanisms
- Define the initial layering and organization of the system
- Define the use-case realizations to be addressed in the current iteration
Identify analysis classes from the architecturally significant use cases
Update the use-case realizations with analysis class interactions

Properties

Event Driven
Multiple Occurrences
Ongoing
Optional
Planned
Repeatable

Staffing

As with Activity: Define a Candidate Architecture, these activities are best carried out by a small team staffed by cross-functional team members. Issues that are typically architecturally significant include performance, scaling, process and thread synchronization, and distribution. The team should also include members with domain experience who can identify key abstractions. The team should also have experience with model organization and layering. From these inputs, the team will need to be able to synthesize a model, or even a prototype, of a solution.

Usage

Usage Guidance

The work is best done in several sessions, perhaps performed over a few days (or weeks and months for very large systems), with iteration between Architectural Analysis and Use-Case Analysis. Perform an initial pass at the architecture in Architectural Analysis, then choose architecturally significant use cases, performing Use-Case Analysis on each one. After (or as) each use case is analyzed, update the architecture as needed to reflect adaptations required to accommodate new behavior of the system and to address potential architectural problems which are identified.

Where the architecture already exists (either from a prior project or iteration), change requests may need to be created to change the architecture to account for the new behavior the system must support. These changes may be to any artifact in the process, depending on the scope of the change.