Artifact: Architectural Model
The system architecture identifies the key strategies for the large-scale organization of the system under development.
Domains: Architecture
Purpose
The architecture describes the key strategic design decisions that affect most or all of the system.
Relationships
Description
Main DescriptionArchitecture is a part of design, and as such, it is concerned almost exclusively with optimization. The scope of architecture is system-wide and so the scope of this optimization has the same breadth.  The architecture represents the strategic design decisions of the system.
Key Considerations

The design is intended to optimize aspects of the analysis model; in terms of architectural design, this means that the selected design patterns must support the analysis model functionality but orchestrate and organize it so that it can execute in an optimal way - optimal, that is, in terms of the ranked set of design criteria.

You should explicitly name and rank the design criteria to make sure you are making good architecture decisions. Take care not to optimize the system too early as this can lead to sub-optimal architectures that are difficult to change downstream.

Tailoring
Impact of not havingAn architecture is an essential aspect of a system design, capturing the strategic design decisions. If missing, the system is un-optimized, unorganized and will both fail to meet its design constraints and be impossible to maintain over the long term.
Representation OptionsIt is best to present the architecture as a model with one or more views, each focusing of different aspects of the architecture.
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