This report provides a comprehensive overview of wireless networks, encompassing various aspects such as data encryption standards, security challenges, energy harvesting techniques, and the application of cellular handsets. The report begins by examining three data encryption standards, including RSA, AES, and Triple DES, highlighting their functionalities and security strengths. It then delves into the security challenges associated with WPAN technologies, specifically Bluetooth and ZigBee, discussing vulnerabilities like Bluesnarfing, Bluejacking, and sniffing attacks. The report further explores energy harvesting, explaining its importance in wireless networks and outlining methods for deriving energy from natural and external sources. Finally, it analyzes the use of cellular handsets, presenting their benefits in terms of storage, communication, customer satisfaction, and internet access. This report is a valuable resource for understanding the complexities and advancements in wireless network technologies.