Reliable Fault Tolerance System for Service Composition in Mobile Ad Hoc Network

A Due to the rapid development of smart processing mobile devices, Mobile applications are exploring the use of web services in MANETs to satisfy the user needs. Complex user needs are satisfied by the service composition where a complex service is created by combining one or more atomic services. Service composition has a significant challenge in MANETs due to its limited bandwidth, constrained energy sources, dynamic node movement and often suffers from node failures. These constraints increase the failure rate of service composition. To overcome these, we propose Reliable Fault Tolerant System for Service Composition in MANETs (RFTSC) which makes use of the checkpointing technique for service composition in MANETs. We propose fault policies for each fault in service composition when the faults occur. Failure of services in the service composition process is recovered locally by making use of Checkpointing system and by using discovered services which satisfies the QoS constraints. A Multi-Service Tree (MST) is proposed to recover failed services with O(1) time complexity. Simulation result shows that the proposed approach is efficient when compared to existing approaches

Promoting Resiliency in Emergency Communication Networks: A Network Interdiction Modeling Approach

Emergency communication networks provide the basis for preparing for, and responding to, manmade and natural disasters. With the increasing importance of information security, emergency network operators such as non-governmental organizations (NGOs), local and national governmental agencies, and traditional network operators must deal with the possibility of sabotage and hacking of such networks. A network interdiction modeling approach is proposed that can be utilized for planning purposes in order to identify and protect critical parts of the network infrastructure. These critical nodes or links represent opportunities where investment or hardening of such infrastructure may reduce or prevent reductions in network traffic flows created by nefarious actors prior, during, or after an emergency or disaster

Design of a Simulator for finding K-best Energy Efficient Paths in Mobile Ad-hoc Networks

MANET stands for "Mobile Ad-hoc Networks". A MANET is a infrasructure less network where every node acts as a router as well as a normal node. The nodes in the network are self configuring, i.e. they configure themself to route the packets with the changing topology. The movement of the nodes in the network is frequent so that the topology changes. The change in topology leads to the disruption in the node connectivity and the end to end routing path. Simulator is a software that provides a complete visibiliy of the network and the contents of the network. In the current work a simulator is designed to show the dynamic movement of nodes by showing their changing neighbors with respect o the node mobility in the network. The path that is established between the source and target node is also visible by tracing path between them. The routing path between the source and destination also changes with changing topology and changing scenario of the network

An Outline of Security in Wireless Sensor Networks: Threats, Countermeasures and Implementations

With the expansion of wireless sensor networks (WSNs), the need for securing the data flow through these networks is increasing. These sensor networks allow for easy-to-apply and flexible installations which have enabled them to be used for numerous applications. Due to these properties, they face distinct information security threats. Security of the data flowing through across networks provides the researchers with an interesting and intriguing potential for research. Design of these networks to ensure the protection of data faces the constraints of limited power and processing resources. We provide the basics of wireless sensor network security to help the researchers and engineers in better understanding of this applications field. In this chapter, we will provide the basics of information security with special emphasis on WSNs. The chapter will also give an overview of the information security requirements in these networks. Threats to the security of data in WSNs and some of their counter measures are also presented

A Framework to Quantify Network Resilience and Survivability

The significance of resilient communication networks in the modern society is well established. Resilience and survivability mechanisms in current networks are limited and domain specific. Subsequently, the evaluation methods are either qualitative assessments or context-specific metrics. There is a need for rigorous quantitative evaluation of network resilience. We propose a service oriented framework to characterize resilience of networks to a number of faults and challenges at any abstraction level. This dissertation presents methods to quantify the operational state and the expected service of the network using functional metrics. We formalize resilience as transitions of the network state in a two-dimensional state space quantifying network characteristics, from which network service performance parameters can be derived. One dimension represents the network as normally operating, partially degraded, or severely degraded. The other dimension represents network service as acceptable, impaired, or unacceptable. Our goal is to initially understand how to characterize network resilience, and ultimately how to guide network design and engineering toward increased resilience. We apply the proposed framework to evaluate the resilience of the various topologies and routing protocols. Furthermore, we present several mechanisms to improve the resilience of the networks to various challenges