March R McFadyen1 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 R McFadyen2 Architecture The UML User Guide depicts architecture as five interlocking views: Design viewImplementation view Process viewDeployment view Use case view An aside

March R McFadyen3 Architecture The UML User Guide depicts architecture as five interlocking views: Design viewImplementation view Process viewDeployment view Use case view View of system as seen by the users. Specifies the forces that shape the architecture Illustrated using Use Cases, statechart diagrams, activity diagrams, interaction diagrams An aside

March R McFadyen4 Architecture The UML User Guide depicts architecture as five interlocking views: Design viewImplementation view Process viewDeployment view Use case view View of system that supports the functional requirements of the system Illustrated using Class diagrams, statechart, activity and, interaction diagrams An aside

March R McFadyen5 Architecture The UML User Guide depicts architecture as five interlocking views: Design viewImplementation view Process viewDeployment view Use case view 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 An aside

March R McFadyen6 Architecture The UML User Guide depicts architecture as five interlocking views: Design viewImplementation view Process viewDeployment view Use case view The view of the system that encompasses the components and files that are used to assemble and release the physical system Primarily addresses configuration management Illustrated using component diagrams, statechart diagrams, activity diagrams, interaction diagrams An aside

March R McFadyen7 Architecture The UML User Guide depicts architecture as five interlocking views: Design viewImplementation view Process viewDeployment view Use case 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 An aside

March R McFadyen8 Architectue - 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: datahowwhere... Bus. Requirements Architecture models Detailed models... An aside

March R McFadyen9 Architectue - an aside from The Data Warehouse Lifecycle Toolkit; Kimball et al.; Wiley&Sons An aside

March R McFadyen10 Layers Pattern 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 Page 450-1

March R McFadyen11 Layers Pattern Benefits/goals: strong cohesion within layers clean/clear definition of interface between layers promotes re-usability, replaceability

March R McFadyen12 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.