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KQML Facilitators

To deliver messages that are incompletely addressed, routers rely on facilitators. A facilitator is a network application which provides useful network services. It maintains a registry of service names; it will forward messages on request to named services. It may provide matchmaking services between information providers and consumers. Facilitators are actual network software agents which have their own KQML routers to handle their traffic and deal exclusively in KQML messages. There is typically one facilitator for each local group of agents. This can translate into one facilitator per local site or one per project; there may be multiple local facilitators to provide redundancy. When each application starts up, its router announces itself to the local facilitator so that it is registered in the local database. When the application exits, the router sends another KQML message to the facilitator, removing the application from the facilitator's database. In this way applications can find each other without there having to be a hand maintained list of local services.