Wireless Networks

VANET is a type of Mobile Ad-hoc network (MANET) that provides wireless communication between close by moving vehicles as well as between vehicles and road side fixed equipment. It requires the vehicles to be equipped with sensors and wireless devices and fixed roadside wireless infrastructure. There are number of research issues like Highly Dynamic Topology, Signal fading, Limited Bandwidth, Intermittent Connectivity, Mobility Modelling, Propagation Model, Routing which needs attention. The scope of this chapter is focused on various advances in Greedy Forwarding routing techniques. Various VANET routing protocols are reviewed and compared in this chapter.

A Review of Trust Management for Mobile Ad Hoc Networks

Establishing trust in Mobile Ad hoc Networks (MANETs) is a challenging task. Trust management consists of various activities like prediction of trust, computation of trust, propagation of trust, aggregation of trust etc. Trust prediction can be done based on past behavior of node, internal parameters of the node, or it can be induction-based or neural-network based. Trust computation can be centralized or distributed. Trust propagation can be social networks based, small world phenomenon based, web of trust based, distributed hash table based. Trust aggregation can be weighted average based, probability based, sequential, conditional-sequential, parallel or subjective logic based. This work presents the review of various activities pertaining to trust management to enable researchers, academicians and practitioners to identify and address trust related issues in a better way.

Direction-Aware Routing Protocol for Delay-Tolerant Network

The main applications of delay tolerant network lie in space research, military, tactical and other security sensitive operations. In these and other applications, secure and energy efficient routing is an important issue in homogeneous and heterogeneous network. This chapter contributes a research work that demonstrates the design, simulation, testing and evaluation of secure, energy efficient and environment independent routing protocol for delay tolerant network. The proposed protocol not only proposed secure approach but also energy efficient approach in homogeneous and heterogeneous environment. The proposed approach utilize sectorization technique to achieve its goals of security, energy efficiency and environment independence. Described in this chapter is a detailed architecture, design, simulation, testing and evaluation of the proposed protocol. Having evaluated these protocols in various simulators, it is concluded that the proposed routing protocol utilized minimum energy and bandwidth and also provided secure transmission.

Mobile Networks and Indian Agricultural Sector

Information dissemination in agricultural sector for its growth using information and communication technology (ICT) as a tool is need of the hour. This can be achieved using information systems. ICT benefits are helpful in exchange and dissemination of information among farming stakeholders. By using the latest tool of mobile technology, farmers can get the current information related to their farming jobs around the clock and at any location, as the mobile network have touched every part/location of the India. Using the features of the mobile-phones like GPS etc. one can get the localized information. Only need is to structure the abundant information available across the various organizations. So, a mobile based agricultural information system framework ‘mAgIDS' has been proposed employing the hybrid mobile application architecture approach. Client-server architecture using the location Application Programming Interface (API) has been proposed. Inference mechanism of the system has implemented on the basis of improved fuzzy rule promotion technique.

Mobile Security

Mobile communication has various important issues such as congestion control, scarcity of radio spectrum, bandwidth utilization, and security. With increased number of threats in mobile devices, security has become the most important issue now-a-days. Security can be considered primarily at two levels; wireless transmission medium and mobile data level, where malicious applications execute their behavior by exploiting vulnerabilities present in mobile OS. The chapter also focuses on the latter one as these attacks can be easily performed by targeting vulnerabilities present in OS. The content is specifically on Android Operating System security as Android has become the largest installed base of mobile platform. This chapter specifies these vulnerabilities and focuses on malicious intentions of latest and sophisticated malware in detail. The chapter covers static and dynamic analysis tools as well as focuses on limitations of these methods for analyses. The results for malware samples with emulator detection capabilities show that these malware behaves more as benign samples.

Dual Scrambled Image Watermarking Algorithm in DWT-SVD Composite Domain

There is an increased risk of copyright violation of multimedia data due to the enormous growth of computer networks that provides fast and error free transmission of any multimedia information. A copyright identifier that may contain some information about the lawful owner is inserted in the contents of the image, without sacrificing its quality. The security levels are increased by using a key value and scaling factor for the embedding and extraction process. The dual scrambled watermark using Arnold and Scrambling sequence is embedded by modifying the singular values of the scrambled cover image's DWT middle frequency sub-band. The simulation was performed on MATLAB 7.7.0 with standard database gray scale images of size 512x512 and watermark of size 64x64 using hybrid dual scrambled watermark schemes. The performance analysis is done on the basis of the degree of scrambling and JPEG compression attack using various parameters. The proposed method achieves better imperceptibility and security for the copyright protection methods.

Self-Organizing Network Solutions

Quality of service (QoS) and network capacity are being insisted as the two dominant factors for the utmost network satisfaction within any mobile network contracts. On the other hand, the heterogeneous network (HetNets), which are constructed based on sub-network layers' cooperation between macrocell and shorter-range applications like micro, femto and relay nodes, are also introduced as an open door to the recent researches towards the desired network satisfaction for the recently upgraded networks like LTE-Advanced (LTE-A). Nevertheless, since any network cooperation is expected to include a number of challenges; this cooperation is not excluded of dealing with degrading effects, such as interference, among the sub-network elements. This chapter presents a detailed discussion in self-organizing network (SON) methodology, as a novel solution to deal with network challenges, e.g. inter-cell interference coordination (ICIC), mobility, power control, etc. to improve the network quality and capacity.

Wireless Sensor Networks Localization

Localization is a fundamental problem in wireless sensor networks. Localization means the determination of geographical locations of sensor nodes, consequently detecting the event location and to initiate a prompt action whenever necessary. The localization process passes with three phases distance and/or angle estimation phase, position phase and algorithm phase. There are many techniques can be used in each phase, some of these techniques may add additional devices, cost, power consumption, or delay to the network. This chapter includes a classification and overview of the most popular localization techniques in each phase, also high lighting the problems of these techniques and their solutions in such a way that helps in understanding localization concepts especially with respect to WSN localization.

Sensing and Performance Issues with Reconfigurable Wireless Transceiver

With the wide applications of wireless communication, it becomes an important factor to keep the pace of the spectrum usage for all the new applications. To improve efficiently the spectrum usage in variety of applications, where the primary users are not active all the time, we can introduce the secondary users to exploit the radio frequency spectrum by not creating any interference to the Primary Users (PU). Unlike the pre-assigned spectrum allocation policy that has been adopted by various wireless technologies, in Cognitive Radio (CR), the whole spectrum is divided into many bands and corresponding channels where spectrum holes exist. The main challenge is thus to sense these holes and accommodate the secondary unlicensed users. In this chapter, proposing the Quantized data fusion sensing which is one of the type of cooperative sensing scheme used for unused spectrum sensing and acknowledgement to secondary signals. Simulation results with error rates are improved by the activity of PU and have been presented.

A logistic-Map-Based PN Sequence for Stochastic Wireless Channels

The work in this chapter mainly focusses on a pseudo-noise (PN) sequence generator which is constructed exploiting the features of one-dimensional chaotic systems such as a logistic map. The use of logistic map to generate strong cryptographic sequences is novel in approach in terms of its use with a range of transmission techniques for wireless communication because it is easy to conceive and requires simple devices to generate the sequence. The generated sequence is used as a spreading sequence in a DS-SS modulation multipath environment with AWGN and Rayleigh fading channel, under various channel fading conditions. The BER curves and channel impulse responses are obtained and compared with the existing linear feedback shift register (LFSR) based PN sequence and Kasami sequence. Results from this comparative analysis indicate that the proposed method generally yields a greater number of reliable, unpredictable and random bits than existing techniques under the same conditions and can be practically implemented for DS-SS scheme as a spreading sequence.