Rendezvous of Mobile Agents When Tokens Fail Anytime

Abstract. We consider the problem of Rendezvous or gathering of multiple autonomous entities (called mobile agents) moving in an unlabelled environment (modelled as a graph). The problem is usually solved using randomization or assuming distinct identities for the agents, such that they can execute dierent protocols. When the agents are all identical and deterministic, and the environment itself is symmetrical (e.g. a ring) it is dicult to break the symmetry between them unless, for example, the agents are provided with a token to mark the nodes. We consider fault-tolerant protocols for the problem where the tokens used by the agents may disappear unexpectedly. If all tokens fail, then it becomes impossible, in general, to solve the problem. However, we show that with any number of failures (less than a total collapse), we can always solve the problem if the original instance of the problem was solvable. Unlike previous solutions, we can tolerate failures occurring at arbitrary times d...

• Type: Conference
• Year: 2008
• Where: OPODIS
• Authors: Shantanu Das, Matús Mihalák, Rastislav Srámek, Elias Vicari, Peter Widmayer
• Keywords: Distributed And Parallel Computing, Mobile Agents, Multiple Autonomous Entities, OPODIS 2008, Unlabelled Environment