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Wireless sensor networks (WSNs) plays a significant role in the field of surveillance, monitoring the real time applications. Regardless its strong ability to handle such tasks, it is difficult to maintain a trade-off between the conflicting goals of network lifetime, transmission delay, high coverage and packet loss. Various solutions have been proposed by the researchers to address these issues comprising the solution in real-time network scenarios. This paper delivers a brief analysis of the solutions addressing recent research problems in WSN comprising conflicting goals, i.e. multi-objective optimization (MOO) technique. Firstly, an illustration of key optimization objective in WSNs is given which constitutes existing issues such as power control, rate control ant routing. Then, an elaboration of various objective functions used in MOO with its merits and demerits is also provided. Later, existing approaches for improving optimizing metric, applications performance of existing approaches and proposed architecture have been discussed.

A broad range of electronics applications involve the long-term exposure to combinations of thermal excursions and vibration with constantly varying amplitudes, and the ultimate life is very often limited by fatigue of the solder joints. The assessment of this is usually based on a combination of simplified accelerated tests and the assumption of simple acceleration factor expressions or models. Neither of the latter can, however, even account for observed effects of accelerated test parameters. To make matters worse common constitutive relations may be strongly misleading. Also, current damage accumulation rules cannot account for major interactions between thermal cycling and vibration or even just for ongoing variations in vibration amplitudes or thermal cycling parameters, respectively. Even if we are ‘just’ aiming to decide between alternative material, design, or process parameters, or to compare a new product to a previous (supposedly similar) one, we should be concerned with the relative performance in service and not just in accelerated tests. The main objective of the present work is to combine two recent mechanistic models into a more comprehensive one that includes interactions between effects of thermal cycling and vibration with varying amplitudes. Important parameters in the resulting model still remain to be determined but a detailed understanding of the underlying mechanisms and the consequences of their interactions for realistic Tin-Silver-Copper (SnAgCu) joints allows for the prevention of surprises, the definition of appropriate test protocols, and the proper interpretation of results. This includes the identification of ‘worst case’ real life scenarios to test for, as well as justification for the use of shear testing in thermal cycling when event detection is not an option. Extension of the model to new alloys is briefly discussed as well.

Sensors are most important components used in lots of electronic devices where human life is associated. A wireless sensor network has many applications where the most important information is to be transferred to the base station in energy efficient manner through multi-hop communication, Due to the tiny size of senor node there is a limited capacity of power and network do not work a long time, further it is very difficult to replace the battery in some hostile area, Therefore an energy consumption scheme or algorithm is needed to extend the network lifetime. The base station is located at the corner of network. In this paper an Improved-Distributed Energy Efficient Clustering (I-DEEC) scheme is proposed and evaluated. The scheme is simulated on MATLAB considering different size of network 100–500 nodes to check the efficiency on different parameters and compared with obtainable protocols DEEC and EESAA. These routing protocols are considered due to functionality of energy efficiency. The developed scheme extends the lifetime of network by selecting the finest shortest path to transmit the data packets. The optimal path can be selected according to the maximum remaining energy at the node for next hop with quality link and minimum number of hops. The Simulation results show that the I-DEEC scheme enhances the lifetime of network 8%-12%, reduces the power utilization 13%-19%, minimizes the delay for transmitting the packets and increases the packet delivery ratio.

A lot of routing protocols have been developed for Wireless sensor networks. Most of them considered the homogeneous network scenario where each node have same capability in terms of processing power, storage, energy etc. In the real scenario, nodes have different values of processing time, storage and energy. Therefore, it is essential to judge the performance of the well accepted routing protocols for heterogeneous wireless sensor networks (H-WSN). Nodes in WSN are dispersed in two ways viz advanced nodes (high energy) and normal nodes. A sensor network works until the nodes do not drain their batteries. Further, it is very difficult to replenish the batteries of the nodes, once they are being deployed to some hostile environment. In this paper, three well accepted WSN routing protocols namely LEACH, FAIR and SEP have been benchmarked for their energy pattern in heterogeneous scenario. Heterogeneity is introduced in terms of initial random energy values given to the sensor nodes. All simulations are done in MATLAB. Different parameters are used for checking the efficacy of the considered routing protocol for H-WSN. Simulation results shows that there is no clear winner for all situations but most of the time FAIR protocol provide better results than LEACH and SEP for considered parameters such as dead nodes decreases per round and packet transfer rate to base station and cluster heads increases.

Adhoc networking field has been interestingly accepted by the research society due to its surprising features. Almost every aspect of the network has been explored by the researchers at some level of detail. A lot of analyses/ surveys have been presented in the literature for showing the performance of well accepted adhoc routing protocols viz. AODV, DSR, AOMDV, CBRP etc. This paper presents some rationale behind these analyses and identifies certain open routing issues which are yet to be worked upon. This work has been done to show and believe that routing in Mobile Adhoc Networks (MANETs) may continue to be an active research effort for the years to come.

As per need of recent applications, new research aspects related to scalability, heterogeneity, and power consumption have been emerged. These issues are supposed to be fixed for better utilization of MANETs. MANET nodes interact through multi-hop routing. AODV is a commonly used on-demand protocol for routing in MANETs. In the existing literature, AODV has been analyzed a number of times but heterogeneity of the nodes has not been addressed. Heterogeneity may be defined as diversity among the nodes in resources or capability. The environment is usually heterogeneous in case of constraint fluid dynamic environment of MANET. In this paper we are analyzing the routing performance as well as energy efficient behavior of AODV routing protocol in both homogeneous and heterogeneous MANETs (H-MANETs), using performance parameters like ratio of delivered packets, throughput, average delay, average power consumption, energy of alive nodes, etc. Heterogeneity has been introduced in terms of different initial energy for all the nodes, unlike the homogeneous scenario. The simulation work has been done using network simulator (NS-2). This work will be helpful to get insight of effects of heterogeneity on energy efficiency and other performance metrics of AODV.

Finite battery power (energy) of the nodes in Mobile Adhoc Networks (MANETs) leads to frequent route failures if not handled properly by a routing protocol. Conditions become worst when a pre assumption is made that all the nodes of the network have equal battery power to communicate. Network scenarios are usually heterogeneous when they are used and realized in real life practical situations. Therefore, considering only homogeneous scenarios restrict the designer to benchmark the performance of a routing protocol to actual practical aspects. Existing protocols and network designs for MANETs not only consider homogeneous scenarios but they are also tested for small size of networks with few numbers of nodes. The throughput achieved by MANETs has been extended its applications to commercial acceptability also. Therefore, to render MANETs services in terms of internet or large number of users, existing protocols should be tested with both large size homogeneous and heterogeneous networks. Thus, scalability becomes another big issue of concern for the better acceptability of a routing protocol for large networks. These limitations make the task of routing very difficult in MANETs. Therefore, routing protocols especially in heterogeneous MANETs (H-MANETs) must be energy efficient and scalable. In this paper, the behavior of some well accepted communication protocols namely AODV, DSR and AOMDV is analyzed for H-MANETs. These protocols have been comprehensively analyzed considering different performance parameters (both traditional and energy related). This paper is aimed to judge the competence of considered protocols in an energy constrained environment with varying network size.

This paper presents the meta-heuristic method of ant colony optimization (ACO) to find optimal paths on terrain map images. The procedure simulates decision-making process of ant colonies as they forage for food. Modifications have been made to the ACO algorithm to solve the optimal path finding problem by optimizing multiple constraints. The number of constraints considered here is two. However, it can effectively be used for more than two constraints.

A directional antenna can provide a more stable path by increasing the coverage range and reducing the no of hops. It can also solves many problems like channel interference and spatial reuse. In Mobile Adhoc Networks (MANETs), the research about directional antennas has been restricted mostly to medium access control. To determine the efficacy of the MANET routing protocols with directional antennas, it is necessary to assess the impact of directional antennas on the performance of routing protocols. In this paper, an attempt has been made to cross couple the MAC and routing layer in order to enable the DSR protocol with directional antenna. To check the scope of this approach it has been compared with the traditional DSR with omni-directional antenna. Simulation results have been generated with NS-2 version 2.29. Simulation results of the paper shows that it can deliver more number of packets with less hop count and less end to end delay as compare to traditional approach of DSR. This approach also faces less energy loss as compare to DSR with omni-directional antenna support.

Efficient routing is a crucial issue in Mobile Adhoc Networks. This paper proposes an improved algorithm for routing in mobile adhoc networks based on the Ant Colony Optimization (ACO) technique. The proposed improved ACO (I-ACO) performs routing by making use of transition probability among nodes along with available pheromone update information in ACO principle. This approach reduces the cost of ant agents. I-ACO has two phases viz route discovery and route maintenance and also utilizes the concept of backtracking when the packets reaches destination node.

Secret sharing is an efficient method of transmitting the image securely. This paper discusses an efficient secret sharing scheme for multiple secret images. It has been shown through the experimental result that the proposed scheme transmits the images secretly and then efficiently recovers the same at the receiver end. This scheme is general in nature and can be applied on any image size. The scheme comprises of the important algorithms namely share generation algorithm and combination algorithm. The share generation algorithm generates the shares of secret multiple images and the combination algorithm combines the specified shares to get the secret images within a very short time and provide high level of security.

Secret sharing is an efficient method of transmitting the image securely. This paper discusses an efficient secret sharing scheme. It has been shown through the experimental result that the proposed scheme transmits the image secretly and then efficiently recovers the same at the receiver end. The scheme is general in nature and can be applied on any image size. The scheme comprises of the important algorithms namely share generation algorithm and combination algorithm. The share generation algorithm generates the share of secret image and the combination algorithm combines the secure parts to get the original image within a very short time with a high level of security.

In order to facilitate communication within a mobile ad hoc network, an efficient routing protocol is required to discover routes between mobile nodes. Power is one of the most important design criteria for adhoc networks as batteries provide limited working capacity to the mobile nodes. Power failure of a mobile node not only affects the node itself but also its ability to forward packets on behalf of others and hence affects the overall network lifetime. Much research efforts have been devoted to develop energy aware routing protocols. In this paper we propose an efficient algorithm, which maximizes the network lifetime by minimizing the power consumption during the source to destination route establishment. As a case study proposed algorithm has been incorporated along with the route discovery procedure of AODV and by simulation it is observed that proposed algorithmpsilas performance is better as compare to AODV in terms of packet delivery ratio and network lifetime for different network scenarios.

A routing strategy that finds a path to be followed by packets from a source node to a destination node used in traditional wired networks cannot be directly applied in ad hoc wireless networks due to their highly dynamic topology, absence of established infrastructure for centralised administration, bandwidth constrained wireless links, and energy constrained nodes. This paper first presents the issues involved in designing a routing protocol and then the different classifications of routing protocols for ad hoc wireless networks. It then discusses the working of several existing routing protocols with their merit and demerits. This survey helps to decide the weaknesses, strength and applicability of an existing routing protocol in different network scenarios and paves the path to develop an efficient routing protocol to cope up with most of the existing problems related to routing in MANETs.