A Family of Design Patterns for Application-Level Gateways

Developers of communication software must confront recurring design challenges involving robustness, efficiency, and extensibility. Many of these challenges are independent of the application-specific requirements. Successful developers resolve these challenges by applying appropriate design patterns. However, these patterns have traditionallybeen locked in the minds of expert developers or buried within complex system source code. The primary contribution of this paper is to describe a family of design patterns that underly many object-oriented communication software systems. In addition to describing each pattern separately, the paper illustrates how knowledge of the relationships and trade-offs among patterns helps guide the construction of reusable communication software frameworks.