To tolerate software faults in sensor applications, Capsule, an efficient log-structured file system for flash memory provides the necessary checkpointing http://www.selleckchem.com/products/CAL-101.html and rollback of object states. These schemes improve the reliability of the network, but the scalability issue must be considered when these schemes are used.2.3. MacroprogrammingMacroprogramming means that a programmer describes a sensor network application as a centralized program and a compiler then generates the node level program. Gummadi et al. designed a simple checkpoint application programming interface (API) for macroprograms and implemented Kairos, a framework that consists of a program language based on Python, a code generator, and a compiler [9]. If we macroprogramming is applied to a sensor application, then the synchronization problem is automatically solved via the Kairos runtime system.

Although macroprogramming has many pros, it is inflexible and too complex for some sensor Inhibitors,Modulators,Libraries applications, such as those related to forest fire detection and enemy tracing.3.?Checkpointing Scheme for Clustering Routing ProtocolsIn this section, we present the design of a checkpointing scheme for clustering routing protocols in detail. First, the essential concept of the clustering routing protocols and its features is described. Then, the design of our scheme and the model for finding the optimal checkpointing interval are presented.3.1. Clustering Routing ProtocolThe main aim of clustering routing protocols (hierarchical protocols) is to efficiently maintain the energy Inhibitors,Modulators,Libraries consumption of sensor nodes by involving them in multi-hop communication within a particular cluster and by performing data Inhibitors,Modulators,Libraries aggregation in order to decrease the number of messages transmitted to the BS [4].

Since the Low-Energy Adaptive Clustering Hierarchy (LEACH) [10] protocol was proposed, there have been many studies on clustering routing protocols such as PEGASIS [11], TEEN [12], ATEEN [13] and OEDSR [14]. These protocols form clusters of sensor nodes based on received signal strength, and they use cluster heads as routers to send the collected information to the Inhibitors,Modulators,Libraries BS.Figure 1 shows the concept of the clustering routing protocol. The depicted network is divided into four clusters, and it elects cluster hea
Many recent studies have focused on various aspects of wireless sensor networks (WSNs) [1].

These networks are composed of the following: A significant number of sensor nodes, which consist of a processing unit with limited computational capability Batimastat and memory; selleck chemical Ganetespib sensors, a wireless communication device; and a limited power source. Although sensor nodes have strong constraints on their energy resources and computational capacity, they can be used for continuous sensing, event detection, event identification, location sensing, and local control of actuators [2].