Mobile search for a black hole in an anonymous ring

Abstract

We address the problem of mobile agents searching a ring network for a highly harmful item, a black hole, a stationary process destroying visiting agents upon their arrival.No observable trace of such a destruction will be evident.The location of the black hole is not known; the task is to unambiguously determine and report the location of the black hole.W e answer some natural computational questions: How many agents are needed to locate the black hole in the ring ? How many suffice? What a-priori knowledge is required? as well as complexity questions, such as: With how many moves can the agents do it ? How long does it take ?.