Types of Attacks and Security Scheme in CRN: A Survey

In The cognitive radio networks includes the primary user (PU) system with authorized spectrum and the secondly user (SU) system without authorized spectrum. When the SUs want to use the spectrum, they have to find the idle channels that are not occupied by the PUs. The devices are consider in this research are stationary and delivering information in between sender to receiver. In this paper we discuss the various security techniques like IDS (Intrusion Detection System), cryptography and other scheme against different attacks in multihop CRN network. The devices are nodes and these nodes are connected with each other through wireless link and exchange data packets and control information. The packet dropping attack is very harmful and also drops the whole data packets in network. The nodes are not known about the attacker because attacker is forward the fake reply of route in between sender to destination. The attacker is detected through not forwarded the data packets to next node or destination node in network. The proposed security scheme is based the calculate hop count and also maintain the record of hop count till the destination is not found. In this paper we highlight the different routing techniques, attacks effect and security proposed by different authors in field of CRN. The whole focus of this paper is on only security and major on packet dropping attack.