Variants of Spreading Messages

In a distributed computing environment a faulty node could lead other nodes in the system to behave in a faulty manner. An initial set of faults could make all the nodes in the system become faulty. Such a set is called an irreversible dynamo. This is modelled as spreading a message among individuals V in a community G = (V,E) where E represents the acquaintance relation. A particular individual will believe a message if some of the individual’s acquaintances believe the same and forward the believed messages to its neighbours. We are interested in finding the minimum set of initial individuals to be considered as convinced, called the min-seed, such that every individual in the community is finally convinced. In this paper we give an upper bound on the cardinality of the min-seed for undirected graphs. We consider some interesting variants of the problem and analyse their complexities and give some approximate algorithms. Submitted: April 2010 Reviewed: November 2010 Revised: February 2011 Reviewed: June 2011 Revised: July 2011 Reviewed: August 2011 Revised: August 2011 Accepted: August 2011 Final: September 2011 Published: October 2011 Article type: Regular paper Communicated by: M. S. Rahman and S. Fujita E-mail addresses: [email protected] (T V Thirumala Reddy) [email protected] (C Pandu Rangan) 684 Thirumala and Pandu Rangan Variants of Spreading Messages