Software system having replicated objects and using dynamic messaging, in particular for a monitoring/control installation of redundant architecture

Claim 1

In a monitoring/control installation comprising: a first processor (1) acting as a primary processor for running a first object-oriented program (2) having first objects (A,B,C,D,E,F,G) and a first dynamic object messaging mechanism (5), and a second processor (1') connected to said first processor via a communication network (10), said second processor acting as a backup processor for running a second object-oriented program (2') having second objects (A',B',C',D',E',F',G') and a second dynamic object messaging mechanism (5') with said second objects being replicas of at least certain ones (D,G) of said first objects which encapsulate non-volatile data, a method for maintaining consistency between said certain ones of said first objects in said first processor and said second objects in said second processor during runtime of said first program, said method comprising the steps of: providing a mark to each of said first objects, said mark being retrievable from processing of an operation invocation on said first objects via said first dynamic object messaging mechanism; setting the mark of said certain ones of said first objects with a specific value; in said first dynamic object messaging mechanism, detecting (51,C1), from each operation invocation on one of said a first objects, whether said one of said first objects has a mark set with said specific value, when said one of said first objects has a mark not set with said specific value, performing (53) the processing of said operation invocation on said one of said first objects, when said one of said first objects has a mark set with said specific value, broadcasting (52) an object call message corresponding to said operation invocation on said one of said first objects via said communication network for time delaying said object call message at an input of said first processor and said second processor by using an atomic and ordered broadcast protocol, and retrieving (54), from said communication network, object call messages and processing said object call messages to perform a succession of corresponding operation invocations on said first objects; and in the second dynamic object messaging mechanism, retrieving (54'), from said communication network, object call messages, and processing said object call messages to perform a succession of corresponding operation invocations on said second objects, so that the successive operations on said certain ones of said first objects in said first processor and the successive operations on the replicas of said certain ones of said first objects in said second processor are performed in the same order.