Level the control layer, which determines the flow of

Level 3 utilizes highly distributed low cost wireless sensors with embedded computation at or near the node. This level will continue to become available to a wider range of applications and organizations as the costs continue to decrease. Additionally, the capability of embedded computation at or near the node will continue to increase as low power, high performing chipsets become more the norm.A wireless sensor network is normally constructed of a collection of nodes, usually containing a power source, computing hardware, radio transceiver, and one or more sensors. Software within the nodes communicates to aggregate sensor data for retrieval by users.WSN ChallengesOperating a network of highly available wireless sensors presents challenges in maintenance, configuration, and sensor node operation; operating management levels including network connectivity, clustering, and data aggregation; managing functional aspects including security, fault monitoring, and performance. As the size of a network of nodes grows to large numbers managing the network’s topology, network configuration, QoS, security, maintenance, and energy use becomes difficult. The application of software defined networking (SDN) is one proposed approach to remedy these challenges.A software defined network is a network where the control layer, which determines the flow of traffic in a network, is decoupled from the underlying networking hardware. The abstraction this creates enables networks with greater agility to be more easily created or modified. By adding this additional layer of abstraction, management of the commonly large and complex networks of DSNs can be simplified.Challenges currently seen in applying software defined networking to wireless sensor networks are collecting data and disseminating network control decisions as the number of nodes increases beyond the capability of a single control node, overhead in the control plane across the network, ensuring network security during attack of a control node, balancing network QoS with power consumption and ensuring effective QoS.Sensor PricingSensor prices continue to drop rapidly year after year, enabling wider adoption.