Abstract. We propose a probabilistic, energy-aware, broadcast calculus for the analysis of mobile ad-hoc networks. The semantics of our model is expressed in terms of Segala's probabilistic automata driven by schedulers to resolve the nondeterministic choice among the probability distributions over target states. We develop a probabilistic observational congruence and a energy-aware preorder semantics. The observational congruence allows us to verify whether two networks exhibit the same observable probabilistic behaviour (connectivity), while the preorder is used to compare the energy consumption of different, but behaviourally equivalent, networks. As an application, we analyse and compare the energy consumption of two well-known automatic repeat request (ARQ)-based error control protocols: stop-and-wait (SW) and go-back-N (GBN).

Abstract-Connectivity and communication interference are two key aspects in mobile ad-hoc networks (MANETs). We propose a process algebraic model targeted at the analysis of both such aspects of MANETs. The framework includes a probabilistic process calculus and a suite of analytical techniques based on a probabilistic observational congruence and an interference-sensitive preorder. The observational congruence allows us to verify whether two networks exhibit the same behaviour. The preorder makes it possible to evaluate the interference level of different, behaviourally equivalent, networks. We show our framework at work on the analysis of the wellknown Alternating Bit Protocol, contrasting the behavior of the standard implementation of the protocol against an alternative implementation that exploits an ideal interference cancellation scheme for CDMA transmissions.

a b s t r a c tConnectivity and communication interference are two key aspects in mobile ad-hoc networks (MANETs). This paper proposes a process algebraic model targeted at the analysis of both such aspects. The framework includes a probabilistic process calculus and a suite of analytical techniques based on a probabilistic observational congruence and an interference-sensitive preorder. The former enables the verification of behavioural equivalences; the latter makes it possible to evaluate the interference level of behaviourally equivalent networks. The result is a comprehensive and effective framework for the behavioural analysis and a quantitative assessment of interference for wireless networks in the presence of node mobility. We show our techniques at work on two realistic case studies.

Abstract-Energy consumption in general and interference in particular are among the most critical issues in wireless networks. In this paper we present the E-BUM calculus, a Energy-aware calculus for Broadcast, Unicast and Multicast communications in wireless ad hoc networks. We formalize the notions of senderand receiver-centered interference and provide efficient proof techniques for verifying the absence of interference between a specific set of nodes.

Abstract-We present a framework to automatically evaluate the performance of Mobile Ad-hoc Networks (MANETs) in terms of different kinds of metrics, such as throughput and energy consumption. We use a probabilistic process calculus to model MANETs; we translate process terms into Markov Decision Processes (MDPs) and use the probabilistic model checker PRISM to automatically evaluate the network performance. We present a case study consisting of a network which uses flooding for communicating, and we analyse how time and energy costs vary when pursuing different power control strategies.Index Terms-process algebra; MANETS; model checking; network throughput; energy consumption I. INTRODUCTION Mobile ad-hoc networks (MANETs) are systems of mobile devices communicating with each other through wireless links without a pre-established networking infrastructure. The devices may rely on exhaustible power sources, such as batteries, and hence have strict requirements regarding their energy consumption. For these reasons, when dealing with networks of this type, communication protocols have to face the problem of providing full connectivity between network devices while maintaining good performance, both in terms of throughput and of energy conservation (see, e.g., [16], [17]).We present a framework to automatically evaluate the performance of MANETs in terms of different kinds of metrics. We use the Probabilistic Energy-aware Broadcast Unicast and Multicast (PEBUM) calculus, introduced in [6], to model MANETs. This is a probabilistic process calculus particularly aimed at providing performance analysis in terms of metrics such as energy conservation and throughput.PRISM [11] is a tool for modelling and analysing systems that exhibit a probabilistic behaviour. It supports, among others, the modelling of Markov Decision Processes (MDPs), where nondeterministic and probabilistic aspects coexist.In this paper we exploit the PRISM tool to perform automated, quantitative verification and analysis of wireless networks for a range of performance metrics. Specifically, we develop a parser to translate a PEBUM process term, representing a network, into an MDP model expressed in the PRISM language. Moreover, we formulate the metrics for computing the time and energy cost of a network transmission in terms of reward structures.We demonstrate the effectiveness of our framework on a case study consisting of a MANET which uses flooding to forward messages. We analyse the performance of the