Design - ADS

Architectural Artifacts for Distributed Systems

• Integrates Management with System Design and Specification
• Offers a Set of Concepts and Tools that help to develop Autonomic Management Systems
• In short, ADS is about an specific Architecture, a Design Model, a number of Domain Specific Languages and Tools for Editing Specifications and generate structured Text (i.e. code)
• Defines three fundamental Artefacts: Element (Unit of Deployment), Contract (Unit of Interoperability) and Policy (Unit of Governance)

Element as the Contractually defined Unit of Deployment

Combination of two distinct Perspectives (abstract) Architectural abstraction (expressing design rules) and Implementation (deployable package)
Composition of Functionality depending on Domains (group Elements for Administration), Facilitiy (coherent Set of functional Capabilities of an Element) and Contracts (Interoperability of Functionality)
Categorised as domain-specific service or general (platform) service
Must be independently manageable or self-managed
requires/provides Facilities, a coherent Set of functional Capabilities in Form of Signatures (Operations and Set of Terminations)

Contracts

Combines Business perspective with Design, Development and Deployment aspects
Defines how Functionality can or must be accesse and documents Obligations and Benefits
Fundamental to understand a Software System, becuse analysis with Contract Specifications and Instantiation can answer important Questions, such as: Is Software Artifact Y similar/comparable/related to Software Artifact X? Are there duplicate Software Artifacts in the Solution/Application? What is the Impact of one Software Artifact on another? What are current Dependencies (directly/indirectly) between Software Architects? What Instances are related to each other ('how', 'why')? What Software Artifacts represent a Compostions? What Software Artifacts are 'composable'?