February13 - Architectural Styles 1 Why Domain-Specific...

Architectural Styles
1
CSCI 477 February 13, 2003
Why Domain-Specific Software Architectures?
Development in specific application domains can be
optimized
Reuse in specific domains is most realistic
reuse in general is too difficult to achieve
focus on particular classes of applications with similar
characteristics
Criteria for successful reuse [Biggerstaff]
well-understood domain
slowly changing
has intercomponent standards
provides economies of scale
fits existing infrastructure

Architectural Styles
2
CSCI 477 February 13, 2003
Software Development
Problem
Space
Solution
Space

Architectural Styles
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CSCI 477 February 13, 2003
Architecture-Based Software Development
Problem
Space
Solution
Space

Architectural Styles
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CSCI 477 February 13, 2003
DSSA-Based Software Development
Problem
Space
Solution
Space

Architectural Styles
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CSCI 477 February 13, 2003
What Is DSSA?
DSSA is an assemblage of software components
specialized for a particular type of task (domain)
generalized for effective use across that domain
composed in a standardized structure (topology) effective for
building successful applications
- Rick Hayes-Roth, 1994
DSSA is comprised of
a domain model ,
reference requirements ,
a reference architecture (expressed in an ADL),
its supporting infrastructure/environment , and
a process/methodology to instantiate/refine and evaluate it.
- Will Tracz, 1995

Architectural Styles
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CSCI 477 February 13, 2003
How Does One Leverage DSSAs?
Reference models
specific configurations for certain application areas
may be effective outside their initial domains
J
discussed previously
e.g., canonical compiler architectures
Idioms & patterns
deal with global organizational structures
application-domain independent
J
to be discussed today
pipe and filter
client-server
blackboard
layered

Architectural Styles
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CSCI 477 February 13, 2003
Definitions of Style
Architectural styles are recurring organizational patterns
and idioms.
- Shaw & Garlan
Established, shared understanding of common design
forms is a mark of a mature engineering field.
- Shaw & Garlan
Architectural style is an abstraction of recurring
composition and interaction characteristics of a set of
architectures.