Preserving the consistency of distributed objects with real-time transactions

In this paper, we study the problem of maintaining the consistency of distributed objects in real-time. Sporadic transactions sent by a set of clients must be processed by a set servers with a bounded end-to-end response time. We propose in this article a solution, following the state machine approach, based on a particular non-preemptive scheduling denoted EDF* (Earliest Deadline First *). The scheduling on the servers is based on timestamps set by the clients and on an end-to-end deadline to respect. The clock of clients and servers are ε synchronized. We establish in this article the feasibility conditions of the distributed real-time system that permits to grant the consistency of distributed objects and the respect of end-to-end deadlines associated to transactions in charge of read/write access to the objects.

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