Adding group communication and fault-tolerance to CORBA

Groupware and fault-tolerant distributed systems stimulate the need for structuring activities around objectgroups and reliable multicast communication. The objectgroup abstraction permits to treat a collection of networkobjects as if they were a single object; clients can invoke operations on object-groups without needing to know the exact membership of the group. Object-groups mainly serve to increase reliability through replication, performance through parallelism, or to distribute data from one sender to a large number of receivers efficiently. This paper describes how object-groups and reliable multicast communication can be added to a CORBA compliant Object Request Broker. It also presents ELECTRA --- a CORBA Object Request Broker whose architecture is pervaded by the group concept. Keywords: Object-Groups, Multicast, Replication, CORBA, Electra, Horus, Isis 1 Statement of Problem 1.1 One World: CORBA Object-oriented programming is believed to be one of today's best programmin...