A Data Flow Pattern Language

Payloads is applicable to any instance where different entities communicate by exchanging messages. It facilitates decreased coupling between messages and the entities that operate with them. The Module data protocol offers several solutions for the inter-module message passing mechanism and could be employed by any modular application. Out-of-band and in-band partitions organizes an application such that different architectural, design and implementation solutions for contradictory requirements can be married. Finally, some of the issues discussed in Data flow architecture and covered in more depth here are: (1) processing with two priority levels at the filter level, (2) changing the behavior at runtime, (3) dynamically adapting to different requirements, (4) improving performance with static composition and (5) facilitating visual programming tools. The presentation follows the guidelines from [MD96]. Each pattern is illustrated with a fairly large number of examples from different areas, such as avionics systems, digital video, hardware, music composition and improvisation, multimedia, operating systems, parallel computers and scientific visualization. The domain diversity confirms the applicability of each pattern and helps readers with different backgrounds achieve a better understanding. I believe that the pattern language offers a broader perspective over the various issues related to these patterns. For each of them, I have also tried to synthesize insights and conclusions from other authors. This approach also improves the clarity of the presentation, allowing the reader to focus on one problem at a time.