On mobile agent verifiable problems

Abstract

We consider decision problems that are solved in a distributed fashion by synchronous mobile agents operating in an unknown, anonymous network. Each agent has a unique identifier and an input string and they have to decide collectively a property which may involve their input strings, the graph on which they are operating, and their particular starting positions. Building on recent work by Fraigniaud and Pelc [J. Parallel Distrib. Comput, vol. 109, pp. 117-128], we introduce several natural new computability classes allowing for a finer classification of problems below MAV or its complement class co-MAV, the former being the class of problems that are verifiable when the agents are provided with an appropriate certificate. We provide inclusion and separation results among all these classes. We also determine their closure properties with respect to settheoretic operations. Our main technical tool, which is of independent interest, is a new meta-protocol that enables the execution of a possibly infinite number of mobile agent protocols essentially in parallel, similarly to the well-known dovetailing technique from classical computability theory.

Redundancy in distributed proofs

“…Finally, verification mechanisms a la proof-labeling schemes were used in other contexts, including the congested clique [34], wait-free computing [26], failure detectors [27], anonymous networks [22], and mobile computing [9,25]. For more references to work related to distributed verification, or distributed decision in general, see the survey [18].…”

Redundancy in Distributed Proofs

“…Finally, verification mechanisms a la proof-labeling schemes were used in other contexts, including the congested clique [27], wait-free computing [20], failure detectors [21], anonymous networks [17], and mobile computing [7,19]. For more references to work related to distributed verification, or distributed decision in general, see the survey [14].…”

Survey of Distributed Decision

“…It is proved that MAV has a complete language for a basic notion of reduction. The complement classes of MAD and MAV have been recently investigated in [8] together with sister classes defined by other ways of interpreting the opinions of the mobile agents.…”