The performance of wireless sensor networks can be improvinged by a holistic approach with respect to security, longevity and connectivity. wWhen the conditions ofin an environment changes., Tthe holistic approach provides an ensuring security for all the layers. In a network, a single security solution for a single layer might not be an efficient solution rather. eEmploying a holistic approach could be the best option.

Some basic principles infor the holistic approach like, in given in a network are given in the figure (2-3). sSecurity it must be ensured for all networks layers of the protocol stack. The cost should be not override the value of the risk at a limited time. The security measures must be able to display deteriorating security if some of the sensors in the network are compromised, out of order or captured by the attacks, and the security measures should be developed to work in a decentralized fashion.

There are some efficient security mechanisms working in each layers. By building security layers, as in the holistic approach, protection could be established for the overall network [3]., and Aas shown in the figure (2.3) is a holistic view of security in wireless sensor networks.