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Wireless sensor networks (WSNs) have a large number of existing applications and is continuously increasing. Thus it is envisioned that WSN will become an integral part of our life in the near future. Direct propagation, chain formation, cluster creation are various techniques by which data is communicated by sensor nodes to the sink. It has been proved that Clustering is an efficient and scalable method to utilize the energy of sensor nodes efficiently. Optimal election of cluster heads is an NP (non deterministic polynomial time)-Hard problem. In our proposed work, a multi-objective optimization algorithm, non dominated sorting genetic algorithm-II based clustering in wireless sensor networks has been proposed. Energy conservation, network lifetime, coverage and load balancing are the four conflicting objective functions used. Our proposed algorithm handles all of these multiple objectives simultaneously. To reduce the computational complexity of the algorithm, efficient non-dominated level update mechanism for sorting has been used, which eliminates the need of applying non dominated sorting from scratch every time. The algorithm returns a solution set consisting of multiple non dominated solutions, wherein every solution is a best solution according to some objective function, in a single run, from which any solution can be chosen based on user preferences. According to our simulation carried on MATLAB, the proposed approach outperforms the established clustering algorithms in terms of network characteristics such as network lifetime, energy consumption and number of packets received.

Vehicular ad-hoc networks (VANETs) have suffered from many risks in the past, such as security privilege and authentication because attackers/hackers always try to disturb the network and break the communication services. The series of attacks that have broken secured communication are network jammer, source sink, and MAC crack, and these attacks are on as denial of service (DoS) attacks. The proposed method is based on the master chock filter concept for the filtration of packets during busy traffic. The IP-CHOCK protocol is implemented along with routing protocol employed in the VANET. The performance of the proposed protocol was evaluated using network simulator NS-2.34. The protocol includes blocking the source IP originator by the DoS attacks and checking the prevention of TCP/UDP flooding and IP sniffing attacks. The evaluation of the protocol was based on the mobility node’s interaction and utilization of bandwidth. The simulation results were analyzed with two different scenarios; first scenario includes 20 mobile nodes and second scenarios with 50 mobile nodes. These two scenarios were performed on the highway transportation condition. The results showed that the throughput, packet delivery ratio, packet loss time, and packet receiving ratio have improved as compared to random IP-trackback protocol. Hence, indicates that the proposed protocol is efficient for intelligent transportation system in VANET.

Software Defined Network (SDN) is the most significant model for the administration of large-scale complex systems, which may require reconfigurations occasionally. It involves the separation of the network control plane and the forwarding plane, where a control plane controls many devices. In this way, the switches forwards packets by the rules defined in the flow table by the controller. Despite the fact, SDN is a new area, it has pulled in a lot of consideration from both the scholar world and industry. This paper investigates the multi-controller placement problem from the viewpoint of cost and load balance factors. The paper proposes an algorithm named Load Balancing with ECP-LL that places controllers by using clustering. The algorithm uses Shannon entropy which avoids poor local minima problems.

Wireless Sensor Networks (WSNs) consist of a large number of spatially distributed sensor nodes connected through the wireless medium to monitor and record the physical information from the environment. The nodes of WSN are battery powered, so after a certain period it loose entire energy. This energy constraint affects the lifetime of the network. The objective of this study is to minimize the overall energy consumption and to maximize the network lifetime. At present, clustering and routing algorithms are widely used in WSNs to enhance the network lifetime. In this study, the Butterfly Optimization Algorithm (BOA) is employed to choose an optimal cluster head from a group of nodes. The cluster head selection is optimized by the residual energy of the nodes, distance to the neighbors, distance to the base station, node degree and node centrality. The route between the cluster head and the base station is identified by using Ant Colony Optimization (ACO), it selects the optimal route based on the distance, residual energy and node degree. The performance measures of this proposed methodology are analyzed in terms of alive nodes, dead nodes, energy consumption and data packets received by the BS. The outputs of the proposed methodology are compared with traditional approaches LEACH, DEEC and compared with some existing methods FUCHAR, CRHS, BERA, CPSO, ALOC and FLION. For example, the alive nodes of the proposed methodology are 200 at 1500 iterations which is higher compared to the CRHS and BERA methods.

Under any routing protocol inconsistency of router create a problem. At the time of link or node failure there is some changes occur in topology which cause some postponement in redesigning of new topology. Router has inconsistent view of network for a few instances. During convergence period, packet may be trapped in forwarding loops. TTL is not adequate when loops are more. It has been watched that even in well oversee systems, failure of connections and router are normal. So as to fulfill the interest for high accessibility if there should arise an occurrence of a failure, quick rebuilding of loop free sending along the ideal ways is significant for a steering plan. The main strength of this paper is that it is not protocol dependent, we can embedded this scheme with any protocol and purpose of this paper is to provide a desirable feature of network, i.e., resilience.

Duplication transforms into a basic thought when spatiotemporal and secure communication required. In the wired network packet may be lost due to congestion but in wireless network packet may be loosed because of many things like- one is congestion and other is link failure, node failure, radio frequency interference, power failure etc. These are called random errors. The Flow of duplicacy increases the congestion in the communication directly which tends to extend the overhead of link. Due to congestion, there is the possibility of many attacks during communication which cannot easily discriminate by the node in the network. In this paper, we proposed dependable and continuous arrangement by inserted Bloom-filter in the packet header at the time of packet broadcasting. It increases the robustness and scalability of Bloom filter based multicast protocol. By the help of the Bloom-filter, functions we design an algorithm which helps to reduce the flow of duplicacy and provide secure communication.

Privacy and Security have become an indispensable matter of attention in the Vehicular Ad-Hoc Network, which is vulnerable to many security threats these days. One of them is the Denial of Service (DoS) attacks, where a malicious node forges a large number of fake identities, i.e., Internet Protocol (IP) addresses in order to disrupt the proper functioning of fair data transfer between two fast-moving vehicles. In this paper, a distributed and robust approach is presented to defend against DoS attacks. In this proposed scheme, the fake identities of malicious vehicles are analyzed with the help of consistent existing IP address information. Beacon packets are exchanged periodically by all the vehicles to announce their presence and to become aware of the next node. Each node periodically keeps a record of its database by exchanging the information in its environment. If some nodes observe that they have similar IP addresses in the database, these similar IP addresses are identified as DoS attacks. However, it can be expected that security attacks are likely to increase in the coming future due to more and more wireless applications being developed onto the well-known exposed nature of the wireless medium. In this respect, the network availability is exposed to many types of attacks. A DoS attack on the network availability is being elaborated in this paper. A model of a product interaction for DoS prevention has been developed called "IP-CHOCK" that will lead to the prevention of DoS attacks. The proposed approach will be able to locate malicious nodes without the requirement of any secret information exchange and special hardware support. Simulation results demonstrate that the detection rate increases when optimal numbers of nodes are forged by the attackers.

The fault-prone nodes in mobile ad-hoc networks (MANETs) degrade the performance of any routing protocol. Using greedy routing mechanisms that tend to choose a single path every time, may cause major data losses, if there is a breakdown of such a path in a fault-prone environment. On the other hand, using all the available paths causes an undesirable amount of overhead on the system. Designing an effective and efficient fault-tolerant routing protocol is inherently hard, since the problem is NP-complete, due to the unavailability of precise path information in adversarial environments [1]. To address the challenges of effective fault-tolerant routing, we present a fault-tolerant routing algorithm (FTAR), based on the ideas of how swarms of natural ants operate[2]. The algorithm is divided into various stages namely initialization, path selection, pheromone deposition, confidence calculation, evaporation and negative reinforcement. Simulation results show that FTAR achieves high packet delivery ratio and throughput as compared to some of the key protocols which do not do fault-tolerance at all. Most importantly, FTAR beats the best fault-tolerant MANET routing algorithm [1] known currently, with respect to the amount of routing overhead incurred, which is an important consideration.

Routing in ad-hoc networks can consume considerable amount of battery power. However, as the nodes in these networks have limited power, routing is very much energy-constrained. Continuous drainage of energy degrades battery performance as well. If a battery is allowed to intermittently remain in an idle state, it recovers some of its lost charge due to the charge recovery effect, which, in turn, results in prolonged battery life. In this paper, we use the ideas of naturally occurring ants' foraging behavior [1] and based on those ideas we design an energy-aware routing protocol, which not only incorporates the effect of power consumption in routing a packet, but also exploits the multi-path transmission properties of ant swarms and, hence, increases the battery life of a node. The efficiency of the protocol with respect to some of the existing ones has been established through simulations.