  Wireless Sensor Networks (WSNs) have gained worldwide attention in recent
years, particularly with the proliferation in Micro-Electro-Mechanical Systems
(MEMS) technology which has facilitated the development of smart sensors. The
paper discusses about classification of WSN and challenges of the Next
Generation WSN. One of the major challenges of Next Generation WSN is reduction
of power consumption. The two approaches are discussed: Ultra-Low-Power
Networks and Energy Harvesting. The paper also discusses about some major
applications as designing low cost secured Intelligent Buildings, In-Home
Health care and Agriculture.
