Reliability for Cluster-based Ad-hoc Networks

The Mobile Ad-hoc Wireless Network (MAWN) is a new and emerging network scheme that is being employed in a variety of applications. The MAWN varies from traditional networks because it is a self-forming and dynamic network. The MAWN is free of infrastructure and as such only the mobile nodes comprise the network. Nodes communicate either directly or through other nodes. To do so each node acts as source, destination, and relay. The virtue of a MAWN is the flexibility this provides however the challenge for reliability analyses is also brought about by this unique feature. The variability and volatility of the MAWN's configuration makes typical reliability methods (e.g. reliability block diagram) inappropriate because no single structure or configuration represents all manifestations of a MAWN. For this reason, new methods are being developed to analyze the reliability of this new networking technology. New published methods adapt to this feature by treating the configuration probabilistically or by inclusion of mobility models. This paper expands upon these works by modifying the problem formulation to utilize a Monte Carlo simulation technique for the reliability analysis of a cluster-based MAWN. The cluster-based MAWN is deployed in applications with constraints or limits on the networking resources such as bandwidth and energy. This paper presents the problem's formulation, a discussion of applicable reliability metrics for the MAWN, and illustration of the method through the analysis of several example networks. Within this paper, a new and innovative use of the general MC simulation approach will be described that allows the practitioner to quickly approximate the reliability of a MAWN and understand the interactions of the characteristics that describe the MAWN; namely node reliability, node mobility, and transport (cluster) layer design. This paper is a follow on from one presented at RAMS 2007.