A new interpretation of the blackboard architecture

This paper describes a new interpretation of Newell's blackboard metaphor of group problem-solving activity. The new interpretation considers the experts of the metaphor to be independent, concurrently active, agents that communicate by posting information on a shared memory (the blackboard). The blackboard in our new interpretation is expanded in functionality and is implemented as a concurrently executing process. The blackboard is able to perform tasks such as agent creation message direction and forwarding, and message censorship. We outline all of these functions and compare them with the conventional (HEARSAY-II derived) interpretation of the metaphor. We end by indicating some of the various ways in which the new interpretation can be used to construct systems that are distributed as well as parallel; as part of this, we show how the blackboard structures of the new interpretation can be recursively composed (embedded) to produce complex systems built from simple components