Biblio

A Network consists of many nodes among which there may be a presence of misbehavior nodes. Delay Tolerant Network (DTN) is a network where the disconnections occur frequently. Store, carry and forward method is followed in DTN. The serious threat against routing in DTN is the selfish behavior. The main intention of selfish node is to save its own energy. Detecting the selfish node in DTN is very difficult. In this paper, a probabilistic misbehavior detection scheme called MAXTRUST has been proposed. Trusted Authority (TA) has been introduced in order to detect the behavior of the nodes periodically based on the task, forwarding history and contact history evidence. After collecting all the evidences from the nodes, the TA would check the inspection node about its behavior. The actions such as punishment or compensation would be given to that particular node based on its behavior. The TA performs probabilistic checking, in order to ensure security at a reduced cost. To further improve the efficiency, dynamic probabilistic inspection has been demonstrated using game theory analysis. The simulation results show the effectiveness and efficiency of the MAXTRUST scheme.

Real world wireless networks usually have diverse connectivity characteristics. Although existing works have identified replication as the key to the successful design of routing protocols for these networks, the questions of when the replication should be used, by how much, and how to distribute packet copies are still not satisfactorily answered. In this paper, we investigate the above questions and present the design of the Hybrid Routing Protocol (HRP). We make a key observation that delay correlations can significantly impact performance improvements gained from packet replication. Thus, we propose a novel model to capture the correlations of inter-contact times among a group of nodes. HRP utilizes both direct delays feedback and the proposed model to estimate the replication gain, which is then fed into a novel regret-minimization algorithm to dynamically decide the amount of packet replication under unknown network conditions. We evaluate HRP through extensive simulations. We show that HRP achieves up to 3.5x delivery ratio improvement and up to 50% delay reduction, with comparable and even lower overhead than state-of-art routing protocols.