MAC Protocols Used by Wireless Sensor Networks and a General Method of Performance Evaluation

Many researchers employ IEEE802.15.4 as communication technology for wireless sensor networks (WSNs). However, medium access control (MAC) layer requirements for communications in wireless sensor networks (WSNs) vary because the network is usually optimized for specific applications. Thus, one particular standard will hardly be suitable for every possible application. Two general categories of MAC techniques exist: contention based and schedule based. This paper explains these two main approaches and includes examples of each one. The paper concludes with a unique performance analysis and comparison of benefits and limitations of each protocol with respect to WSNs

Wireless Information Systems in Support of Green iSchools

Becoming a green iSchool requires information infrastructure development. Wireless information systems are important for information infrastructure development. This paper assesses how wireless information systems can support creating green iSchools. Wireless information systems can be built from wireless networks such as Wireless Local Area Networks (WLANs), Wireless Wide Area Networks (WWANs), and Wireless Sensor Networks (WSNs). Wireless networks can reduce the fossil fuel combustion from transportation while using fewer infrastructures than wired networks. A WSN can otherwise help increase energy efficiency for school buildings. With low cost energy efficient sensor nodes placing at multiple locations, data gathering can be more effective. And this in turn helps energy use in a school building be more efficient