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Architecture
Architecture involves the set of significant decisions about
the organization of a software system,
decisions concerning:
•its structural elements and their interfaces
•its behaviour as specified in the collaborations
•its composition into progressively larger subsystems
March 2002
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Architecture
An aside
The UML User Guide depicts architecture as five
interlocking views:
Design view
Implementation view
Use case
view
Process view
March 2002
Deployment view
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Architecture
An aside
The UML User Guide depicts architecture as five
interlocking views:
View of system as seen
by the users.
Design view
Implementation view
Use case
view
Process view
March 2002
Deployment view
91.3913
R McFadyen
Specifies the forces
that shape the
architecture
Illustrated using Use
Cases, statechart
diagrams, activity
diagrams, interaction
diagrams
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Architecture
An aside
The UML User Guide depicts architecture as five
interlocking views:
Design view
Implementation view
Use case
view
Process view
March 2002
Deployment view
91.3913
R McFadyen
View of system that
supports the functional
requirements of the
system
Illustrated using Class
diagrams, statechart,
activity and, interaction
diagrams
4
Architecture
An aside
The UML User Guide depicts architecture as five
interlocking views:
Design view
Implementation view
Use case
view
Process view
March 2002
Deployment view
91.3913
R McFadyen
View of system that
supports its
concurrency and
synchronization issues
Addresses the
performance,
scalability, and
throughput of the
system
Illustrated using Class
diagrams, statechart,
activity and, interaction
diagrams
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Architecture
An aside
The UML User Guide depicts architecture as five
interlocking views:
Design view
The view of the system
that encompasses the
Implementation view components and files
that are used to assemble
and release the physical
Use case
system
view
Process view
Deployment view
Primarily addresses
configuration
management
Illustrated using
component diagrams,
statechart diagrams,
activity diagrams,
interaction diagrams
March 2002
91.3913
R McFadyen
6
Architecture
An aside
The UML User Guide depicts architecture as five
interlocking views:
Design view
Implementation view
Use case
view
Process view
Deployment view
The view of the system
that encompasses the
nodes that form the
system’s topology on
which it executes
Primarily addresses
distribution and
installation of parts that
make up the physical
system
Illustrated using
deployment diagrams,
statechart, activity and,
interaction diagrams
March 2002
91.3913
R McFadyen
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Architectue - an aside
An aside
Another approach to architecture, due to John A. Zachman of
Zachman International, previously of IBM
Architectural framework is presented in a matrix where rows are
levels of detail and columns are major architectural areas
In The Data Warehouse Lifecycle Toolkit, P 321:
data
how
where
...
Bus. Requirements
Architecture models
Detailed models
...
March 2002
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R McFadyen
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Architectue - an aside
An aside
from The Data Warehouse Lifecycle Toolkit; Kimball et al.;
H igh Level W arehouse Technical Architecture
Wiley&Sons
The Front Room
The Back Room
Metadata
Source
Catalog
Sys tems
Data
Staging
Services
Presentation Serv ers
- W arehous e Brows ing
- Extract
Dimensi onal Da ta Mar ts wi th
- T ransformation
only aggre gate d data
- Load
- J ob Control
Data Staging
T he Data
Conformed
Dimensions &
Conformed
Facts
Desktop Data
Access Tools
- Acc es s and Sec urity
- Query Management
- Standard Reporting
W arehous e
BUS
Area
Query
Services
Standard
Reporting Tools
Application Models
(e.g. data mining)
- Activity Monitor
Downstream /
operational
systems
Dimensiona l Data Marts
includi ng a tomic data
Key
Data
Service
Element
Element
March 2002
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R McFadyen
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Layers Pattern
Page 450-1
The Layers Pattern organizes the large-scale logical/conceptual
structure of a system into discrete layers with distinct, but related
responsibilities.
Each layer exhibits high cohesion.
Lower layers are low-level providing general services; higher
levels are more application specific.
Collaboration and coupling is from higher to lower layers
Layers defines an N-tier model
March 2002
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R McFadyen
10
Layers Pattern
Benefits/goals:
•strong cohesion within layers
•clean/clear definition of interface between layers
•promotes re-usability, replaceability
March 2002
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R McFadyen
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Typical Layers in an Information System - Fig 30.1, P. 451
Layers is a pattern
where the structure
of a system is
organized into
discrete layers
where each layer is
highly cohesive,
and where higher
layers are more
application
specific, lower
layers are more
low-level and
service oriented.
March 2002
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R McFadyen
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