Intrinsic Definition in Software Architecture Evolution

Abstract

Incremental change is intrinsic to both the initial development and subsequent evolution of large complex software systems. The talk discusses both, the requirements for and the design of, an approach that captures this incremental change in the definition of software architecture. The predominate advantage in making the definition of evolution intrinsic to architecture description is in permitting a principled and manageable way of dealing with unplanned change and extension.

Intrinsic definition also facilitates decentralized evolution in which software is extended and evolved by multiple independent developers. The objective is an approach which permits unplanned extensions to be deployed to end users with the same facility that plugin extensions are currently added to systems with planned extension points. The talk advocates a model-driven approach in which architecture definition is used to directly construct both initial implementations and extensions / modification to these implementations.

An implementation of intrinsic evolution definition in Backbone is presented – an architectural description language (ADL), which has both a textual and a UML2, based graphical representation. The talk uses Backbone to illustrate basic concepts through simple examples and reports experience in applying it and its associated tool support to larger examples.