In this paper, we propose a token based algorithm to solve the group mutual exclusion (GME) problem for ad hoc mobile networks. The proposed algorithm is adapted from the RL algorithm in [WWV98] and utilizes the concept of weight throwing in [Tse95]. We prove that the proposed algorithm satisfies the mutual exclusion, the bounded delay, and the concurrent entering properties. The proposed algor...

We present a simple and effective approximated backward reachability algorithm for parameterized systems with existentially and universally quantified global conditions. The individual processes operate on unbounded local variables ranging over the natural numbers. In addition, processes may communicate via broadcast, rendez-vous and shared variables. We apply the algorithm to verify mutual exc...

The main objective of this lecture is to prove a lower bound on the number of registers (variables) required for any distributed algorithm that solves the Mutual Exclusion problem. We will work in an asynchronous shared memory model. Recall that Peterson’s Algorithm on n processors solves Mutual Exclusion by using two arrays, each of size n. So 2n is an upper bound on the number of registers ne...

Mutual Exclusion is one of the most studied topics in distributed systems where processes communicate by asynchronous message passing. It is often necessary for multiple processes at different sites to access a shared resource or data called a critical section (CS) in distributed systems. A number of algorithms have been proposed to solve the mutual exclusion problem in distributed systems. In ...

In this paper, we propose a self-stabilizing mutual exclusion algorithm using tokens for the mobile ad hoc network. Since the liveness condition of mutual exclusion can’t be guaranteed by any algorithm for a mobile ad hoc network with arbitary mobility, we consider a mobile ad hoc network with restricted mobility. Our algorithm is based on the dynamic virtual rings formed by the token circulati...

A mobile ad hoc network can be defined as a network that is spontaneously deployed and is independent of any static network. The network consists of mobiles nodes with wireless interfaces and has arbitrary dynamic topology. The network suffers from frequent link formation and disruption due to the mobility of the nodes. A clustering method is used for obtaining a hierarchical organization for t...

Deadlock-free algorithms that ensure mutual exclusion crucially depend on timing assumptions. In this paper, we describe our experience in automatically verifying mutual-exclusion and deadlock-freedom of the Fischer and Lynch-Shavit algorithms, using the model checker modulo theories mcmt. First, we explain how to specify timing-based algorithms in the mcmt input language as symbolic transition...

A Mobile Ad hoc NETwork (MANET) is a collection of wireless mobile nodes forming a temporary network without the use of any existing infrastructure or centralized administration. Due to the dynamic topology of the network and the resource constraints, implementing distributed algorithms in MANETs is a challenging task. This paper proposes a new architecture to solve the problem of mutual exclus...

Fathers and fatherhood are back on the policy agenda. Over the past two decades questions have been raised within New Zealand and comparative countries as to the status of men and the rights and responsibilities of fatherhood. Such questions arise at a time when fathers have become increasingly marginalised, especially within the context of the home. As the role of breadwinner and provider has ...

Peterson’s algorithm [G.L. Peterson, Myths about the mutual exclusion problem, Inform. Process. Lett. 12 (3) (1981) 115–116] for mutual exclusion has been widely studied for its elegance and simplicity. In Peterson’s algorithm, each process has to cross n− 1 stages to access the shared resource irrespective of the contention for the shared resource at that time, and allows unbounded bypasses. I...