1.1.1 Types of Sensor Networks
Terrestrial WSNs: - In Terrestrial WSNs, nodes are distributed in a given area either in a pre-planned manner (sensor nodes are placed according to optimal placement, grid placement, 2-d and 3-d placement models) or in an ad hoc manner (sensor nodes are randomly placed in the target area by dropping it from plane). After all battery power is limited and it cannot be reenergized, terrestrial sensor nodes must be provided with a maximum power source such as solar cells.
Underground WSNs: - In this network, sensor nodes are hidden in a cave or underground or mine that monitors the underground conditions. Sink nodes are deployed above the ground to forward the collected information to the base station from the sensor nodes. These …show more content…
Only one single key is saved in the nodes ' memory and once enforced in the network, there is no requirement for a node to perform key exchange or key discovery, however, all the nodes in communication coverage area can transfer messages employing the key which they already share. On the other side, this strategy suffers a serious disadvantage that adjustment of a single node would lead compromise of the whole network by the shared key. Hence it fails in offering the basic secure need of a sensor network by building it easy for an antagonist attempting to attack.
An alternative key distribution strategy is fully pair-wise keys strategy, such as each node in the sensor network shares a different key with each other node in the network. The major problem with this pair-wise key strategy is its poor scalability. The no. of keys that must be saved in every node is proportional to the total no. of network nodes. However sensor nodes are resource-restrained, this brings important overhead which restricts the mechanism’s availability except for it can only be efficiently utilized in smaller
Terrestrial WSNs: - In Terrestrial WSNs, nodes are distributed in a given area either in a pre-planned manner (sensor nodes are placed according to optimal placement, grid placement, 2-d and 3-d placement models) or in an ad hoc manner (sensor nodes are randomly placed in the target area by dropping it from plane). After all battery power is limited and it cannot be reenergized, terrestrial sensor nodes must be provided with a maximum power source such as solar cells.
Underground WSNs: - In this network, sensor nodes are hidden in a cave or underground or mine that monitors the underground conditions. Sink nodes are deployed above the ground to forward the collected information to the base station from the sensor nodes. These …show more content…
Only one single key is saved in the nodes ' memory and once enforced in the network, there is no requirement for a node to perform key exchange or key discovery, however, all the nodes in communication coverage area can transfer messages employing the key which they already share. On the other side, this strategy suffers a serious disadvantage that adjustment of a single node would lead compromise of the whole network by the shared key. Hence it fails in offering the basic secure need of a sensor network by building it easy for an antagonist attempting to attack.
An alternative key distribution strategy is fully pair-wise keys strategy, such as each node in the sensor network shares a different key with each other node in the network. The major problem with this pair-wise key strategy is its poor scalability. The no. of keys that must be saved in every node is proportional to the total no. of network nodes. However sensor nodes are resource-restrained, this brings important overhead which restricts the mechanism’s availability except for it can only be efficiently utilized in smaller