The mechanisms to decide on caching a packet on its way of transmission to a faulty node in wireless sensor networks based on the analytical models and mathematical evaluations

The behavior of sensor networks is highly unpredictable because of randomness in individual node state and network structure. When a node fails, the packets transmitted to this faulty node is dropped if it is not cached by an operational node. In this paper some analytical models based on fault tolerance mechanisms have been proposed to be used in different aspects of caching a packet regarding this situation. The ratio of the time to be allocated to cache the packet by an operational node and the expected repair time of the faulty node represents a threshold that decides whether this operational node should cache the packet or it will pass the packet to a selected neighbor node. Analytical models developed in this paper have made detail and clear inspections in these respects. Distributed caching mechanism has been described in this paper, which makes a way to use the energy of the nodes in a distributed fashion to cache a packet. The models and mechanisms, described in this paper are distributed and highly scalable, which ensure energy efficient caching of a packet and thus highly applicable to the sensor networks.