4+1 architectural view model. Illustration of the 4+1 Architectural View Model. 4+1 is a view model designed by Philippe Kruchten for "describing the architecture of software-intensive systems, based on the use of multiple, concurrent views".[1] The views are used to describe the system from the viewpoint of different stakeholders, such as end-users, developers and project managers.
The four views of the model are logical, development, process and physical view. In addition selected use cases or scenarios are utilized to illustrate the architecture serving as the 'plus one' view. Hence the model contains 4+1 views:[1] Logical view : The logical view is concerned with the functionality that the system provides to end-users. Department of Defense Architecture Framework. DoD Architecture Framework v1.5.[1] DoDAF Architecture Framework Version 2.0[2] This Architecture Framework is especially suited to large systems with complex integration and interoperability challenges, and it is apparently unique in its employment of "operational views".
These views offer overview and details aimed to specific stakeholders within their domain and in interaction with other domains in which the system will operate.[3] Overview[edit] TOGAF® 9.1.