Abstract

One of the major important aspects of wireless sensor networks WSNs is their capability to collect and process huge amounts of information in parallel with the help of small power limited devices enabling their use in observation target detection and various other monitoring applications Recently new ideas have been proposed to develop cognitive WSNs CWSNs to enhance awareness about the network and environment and make adaptive decisions based on the application goals A CWSN is a special network which has many constraints compared to traditional wireless network But the major problem is security In this paper discovering various security threats in these networks and various defense mechanisms to counter these vulnerabilities Various types of attacks on CWSNs are categorized under different classes based on their natures and targets and corresponding to each attack class appropriate security mechanisms are discussed