Koha System Architecture

Koha system architecture is organized into three layers, each of which consists of a number of components. 1) Storage Layer 2) Business Logic Layer 3) Application Layer.
Storage Layer: This layer is responsible for the physical storage of bibliographic data or any file uploaded in koha system. It is comprising of Database Drivers, RDBMS wrappers and File System API.
Business Logic Layer: This layer deals with the Koha business model. The koha core along with the various modules Acquisition, Cataloguing, Circulation, Patron, Lists, Koha Administration, Tools, Authorities, Serials, Reports etc.
Application Layer: The application layer contains components that communicate with the outside world. The two Koha interfaces are most important koha staff client and koha opac.
As koha is a open source software it is also having opening for integrating other customized tool within the software. Like for example PHP code may be used for writing custom utilities.
Each individual layer only invokes the layer beneath it; the application layer may not use the storage layer directly, rather the components of application layer uses the components of business logic layers and that it turns uses the storages layer API.
With reference to API the modules are written using perl scripting language as well as the architecture remains open to implement other scripting language to design and develop specilised tools or utilities.
Henceforth the source code is organized to follow the three-layer architecture, so it makes easy implementation of the software.