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AbstractWireless communication technology has changed and expanded at an incredible rate particularly within the last few years. Moreover, the demand for wireless communication services has increased due to the fast growth of wireless technology and new revolutionary applications. Nowadays, Wi-Fi is the technology used by most and is widely deployed in homes, offices, coffee shops and airports, etc. It is also widely used with smart phones, tablets and smart TVs, etc. An emerging technology known as Li-Fi is used to off-load data from existing Wi-Fi networks to provide more capacity or where Wi-Fi is not allowed such as, in hospitals, petrochemical plants and aircrafts. After a comprehensive literature survey, there is no extensive comparison of this revolutionary new wireless technology (Li-Fi) with Wi-Fi. This proposed research compares between Light-Fidelity and Wireless-Fidelity in terms of: Radio channel, data rate, range, network size, multiple access, security and applications. In conclusion, Li-Fi technology provides a large license free bandwidth, higher data rate, more safety and availability with a high level of security and privacy compared to Wi-Fi.

Third generation mobile systems are seen as the technology to bring new broadband services to the mobile user. This paper discusses UMTS/GPRS technologies applying to tactical communication networks. A detailed description of the 3G technologies is provided, and their application in Military Environments is studied in depth. The paper discusses the introduction of new services into Military- networks, which is improving tactical effectiveness, while also dealing with major improvements in spectrum efficiency, capability and functionality compared with today's non-voice mobile services. The schemes and mechanisms for controlling the traffic in order to achieve the per-hop behavior is still an open problem in the Military wireless environment. GPRS and UMTS can provide military with access to many different demanding tactical services. Nevertheless, in order to preserve the unique characteristics of military systems, a number of vital issues have to be carefully addressed, including security mechanisms and fraud detection. Thus, the UMTS/GPRS tactical network is a challenge for the military telecommunication. It will provide a massive boost to mobile data usage and usefulness. Although, many problems are still not solved, for instance effective radio access schemes and traffic management, the information that can be transfer in this tactical network environment are very useful except for the communications and for the command and control systems. © 2004 IEEE.

Wireless Sensor Network (WSN) is an emerging technology that shows great promise for various futuristic applications both for mass public and military. The sensing technology combined with processing power and wireless communication makes it lucrative for being exploited in abundance in future. The inclusion of wireless communication technology also incurs various types of security threats. The intent of this paper is to investigate the security related issues and challenges in wireless sensor networks. We identify the security threats, review proposed security mechanisms for wireless sensor networks. We also discuss the holistic view of security for ensuring layered and robust security in wireless sensor networks.

Wireless Sensor Network (WSN) is an emerging technology that shows great promise for various futuristic applications both for mass public and military. The sensing technology combined with processing power and wireless communication makes it lucrative for being exploited in abundance in future. The inclusion of wireless communication technology also incurs various types of security threats. The intent of this paper is to investigate the security related issues and challenges in wireless sensor networks. We identify the security threats, review proposed security mechanisms for wireless sensor networks. We also discuss the holistic view of security for ensuring layered and robust security in wireless sensor networks.

This review is divided into three sections: technologies for monitoring physiological parameters; biosensors for chemical assays and wireless communications technologies including image transmissions. Applications range from monitoring high risk patients for heart, respiratory activity and falls to sensing levels of physical activity in military, rescue, and sports personnel. The range of measurements include, heart rate, pulse wave form, respiratory rate, blood oxygen, tissue pCO2, exhaled carbon dioxide and physical activity. Other feasible measurements will employ miniature chemical laboratories on silicon or plastic chips. The measurements can be extended to clinical chemical assays ranging from common blood assays to protein or specialized protein measurements (e.g., troponin, creatine, and cytokines such as TNF and IL6). Though the feasibility of using wireless technology to communicate vital signs has been demonstrated 32 years ago (1) it has been only recently that practical and portable devices and communications net works have become generally available for inexpensive deployment of comfortable and affordable devices and systems.

Wireless communication systems, since their inception in the form of cellular communications, have spread rapidly throughout the western world and the trend is catching on in the developing countries as well. These sys­ tems have caused revolutionary changes in the way we live. Cellular Commu­ nications have become important both as means of communication and as a new domain ofcommercial enterprise. Hand held telephones are now rapidly replacing the fixed telephone and in less than twenty years, the number of subscribers has reached nearly three quarters of a billion. In a short span of twenty years, the cellular communications progressed from the first genera­ tion to the third generation systems, which started operations in Japan on October 1,2001. The first generation wireless technology, which was thought to be obsolete is now being used for fixed wired telephony in several coun­ tries of Asia, Africa and Latin America. As some commentator said in 1983, the cellular system is the best thing that has happened in telecommunications since the introduction ofcomputers to the masses. This book is written to provide readers with the fundamental concepts ofwireless communications. It is intended for a graduate course on wireless communications but it could be easily adopted at the senior level by skipping material involving difficult mathematical manipulations. The text does not go through the rigorous material on mathematical treatment of electromagnetic waves and propagation, rather it emphasizes more on the practical aspects of this

NPS Cebrowski Institute ; The research is driven by the lack of communication capabilities observed by front-line troops, while providing disaster relief, humanitarian assistance, or conducting full-scale combat operations. Traditionally, the U.S. and Allied ground troops are briefed a mission order, allocated specific communication assets, and deployed to diverse austere environments. Since communication failures and compromises have increasing potential with mission importance, the level of sophistication is significantly geared toward security and reliability. Therefore, communication capabilities are limited to prevent expediential cost increases. Our research goal is to increase the communication capabilities, maintain security and reliability, and reduce the overall cost.