Departmental Papers (CIS)

Date of this Version

May 1991

Document Type

Journal Article


Copyright 1991 IEEE. Reprinted from IEEE Transactions on Computers, Volume 40, Issue 5, May 1991, pages 573-583.

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In a large class of hard-real-time control applications, components execute concurrently on distributed nodes and must coordinate, under timing constraints, to perform the control task. As such, they perform a type of atomic commitment. Traditional atomic commitment differs, however, because there are no timing constraints; agreement is eventual. We therefore define timed atomic commitment (TAC) which requires the processes to be functionally consistent, but allows the outcome to include an exceptional state, indicating that timing constraints have been violated. We then present centralized and decentralized protocols to implement TAC and a high-level language construct that facilitates its use in distributed real-time programming.


atomic commitment, distributed protocols, distributed real-time systems, fault tolerance, language constructs



Date Posted: 25 July 2008

This document has been peer reviewed.