NETWORK ARCHITECTURE

Definition:
The applications architecture is specified on the basis of business requirements. This involves defining the interaction between application packages, databases, and middleware systems in terms of functional coverage. This helps identify any integration problems or gaps in functional coverage. A migration plan can then be drawn up for systems which are at the end of the software life cycle or which have inherent technological risks.
Applications Architecture means managing how multiple applications are poised to work together. It is different from Software Architecture which deals with design concerns of one application.[citation needed]
[edit] Application Architecture Strategy
Strategy by definition is a stance and does not involve any action. Application Architecture Strategy involves ensuring the applications and the integrations align with the growth strategy of the Organization. If an organization is a manufacturing organization with fast growth plans through acquisitions, the application architecture should be nimble enough to encompass inherited legacy systems as well as other large competing applications.
[edit] Application Architecture Patterns
Applications can be classified in various types depending on the Application Architecture Pattern they follow.
A "pattern" has been defined as: "an idea that has been useful in one practical context and will probably be useful in others”
To create patterns, one needs building blocks. Building blocks are components of software, mostly reusable, which can be utilised to create certain functions. Patterns are a way of putting building blocks into context and describe how to use the building blocks to address one or multiple architectural concerns.
An application is a compilation of various functionalities all typically following the same pattern. This pattern defines the application’s pattern
All applications follow one of the following industry-standard Application Architecture Patterns
Client-Proxy Server: Acts as a concentrator for many low-speed links to access a server.
Customer Support: Supports complex customer contact across multiple organisations.
Reactor: Decouples an event from its processing.
Replicated Servers: Replicates servers to reduce burden on central server.
Layered Architecture: A decomposition of services such that most interactions occur only between neighboring layers.
Pipe and Filter Architecture: Transforms information in a series of incremental steps or processes.
Subsystem Interface: Manages the dependencies between cohesive groups of functions (subsystems).
Service: Users accessing transactions on a 24x7 basis (a.k.a. user-to-business)
Collaboration: Users working with one another to share data and information (a.k.a. user-to-user)
Information Aggregation: Data from multiple sources aggregated and presented across multiple channels (a.k.a. user-to-data)
Extended Enterprise: Integrating data and processes across enterprise boundaries (a.k.a. business-to-business)
The right application pattern depends on the organisation's industry and use of the component applications. An organisation could have a mix of multiple patterns if it has grown both organically and through acquisitions