DISTRIBUTED DATA PROCESSING SYSTEMS

摘要

A distributed data processing system comprises a plurality of data processing nodes interconnected by a data communications network. Each node runs a plurality of agents some of which are client agents and some of which are server agents which provide services for the client agents. Each node has a message handler for sending request messages from the client agents to the server agents and for returning responses from the server agents to the client agents. At least some of the server agents replicated so as to provide a plurality of instances of the same service. In the event that a server agent does not respond to a request message from a client agent, the message handler sends the request message to another server agent providing an alternative instance of the same service.This provides resilient against failure of a particular instance of a service.