Handling message semantics with Generic Broadcast protocols

Message ordering is a fundamental abstraction in distributed systems. However, ordering guarantees are usually purely “syntactic,” that is, message “semantics” is not taken into consideration despite the fact that in several cases semantic information about messages could be exploited to avoid ordering messages unnecessarily. In this paper we define the Generic Broadcast problem, which orders messages only if needed, based on the semantics of the messages. The semantic information about messages is introduced by conflict relations. We show that Reliable Broadcast and Atomic Broadcast are special instances of Generic Broadcast. The paper also presents two algorithms that solve Generic Broadcast.

Authors and Affiliations

1. Hewlett-Packard Laboratories, Software Technology Laboratory, Palo Alto, CA 94304, USA (e-mail: pedone@hpl.hp.com) , , , , , , US

   F. Pedone

2. Communication Systems Department, EPFL – Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland (e-mail: andre.schiper@epfl.ch) , , , , , , CH

   A. Schiper

Received: August 2000 / Accepted: August 2001

Reprints and permissions