Architectural design of a multi-agent system for handling metadata streams
Don G. Cruickshank, Luc Moreau, David De Roure · 2001
We have designed a multi-agent architecture to deliver metadata streams synchronously with multimedia streams over a wide-area network. To this end, we have devised a simple protocol for synchronising agents to a media clock. This protocol defines the concept of deadline, after which servers can drop data because it can no longer reach clients in time. We also introduce a new concept of contract as a first-class entity representing a successful subscription; a contract is used by agents as a session identifier during the navigation of streams. Quality of service is a vital element of this architecture because of the need to deliver metadata on time. As a result, our architecture supports various communication protocols, including UDP, RMI, SSL, or multicast. This resulted in a return to a more declarative form of speech acts, totally orthogonal to a notion of virtual communication channel used to manage the quality of service of communication.