Survey on Security Issues in Cognitive Radio Network <s> I. INTRODUCTION <s> The cellular wireless market has begun the transition to data centric services including high speed internet access, video, high quality audio, and gaming. Communications technology can meet the need for very high data link speeds, and can also improve network throughput, but dramatically more spectrum will be needed to provide ubiquitous wireless data service. Cognitive radio is a new technology that allows spectrum to be dynamically shared between users. It offers the potential to dramatically change the way spectrum is used in systems and to substantially increase the amount of spectrum available for wireless communications. This paper introduces cognitive radio and explains the promise, possible operating modes, and benefits it may offer. <s> BIB001 </s> Survey on Security Issues in Cognitive Radio Network <s> I. INTRODUCTION <s> In November/2004, we witnessed the formation of the first worldwide effort to define a novel wireless air interface (i.e., MAC and PHY) standard based on Cognitive Radios (CRs): the IEEE 802.22 Working Group (WG). The IEEE 802.22 WG is chartered with the development of a CR-based Wireless Regional Area Network (WRAN) Physical (PHY) and Medium Access Control (MAC) layers for use by license-exempt devices in the spectrum that is currently allocated to the Television (TV) service. Since 802.22 is required to reuse the fallow TV spectrum without causing any harmful interference to incumbents (i.e., the TV receivers), cognitive radio techniques are of primary importance in order to sense and measure the spectrum and detect the presence/absence of incumbent signals. On top of that, other advanced techniques that facilitate coexistence such as dynamic spectrum management and radio environment characterization could be designed. In this paper, we provide a detailed overview of the 802.22 draft specification, its architecture, requirements, applications, and coexistence considerations. These not only form the basis for the definition of this groundbreaking wireless air interface standard, but will also serve as foundation for future research in the promising area of CRs. <s> BIB002
In the wireless world communication is on the rise changing and increasing subscriber base. Applications continue to increase the occurrence of high data throughput. The fast emergent request for broadband wireless service, these have led to the increase of several wireless technologies. These technologies always grow with ever-increasing competencies. IEEE has offered multiple standards under licensed frequency band. By using IEEE 802.22 frequency band of unlicensed frequency is being utilized. After the Federal Communication Commission (FCC), working group (WG) is working to finalize the standard of 802.22 which passed the resolution. 802.22 is also called wireless radio area network (WRAN) or cognitive radio network (CRN) by IEEE BIB001 .While 802.16a/d/e and 802.20 have focused on providing the necessary infrastructure to create wireless metropolitan area networks (MAN) which has the radius of approximately 1km to 5 kms, 802.22 is pursuing to define a standard Capable of serving vast regions up to 100km in size  . As a software base most of the radio function that run on programmable electronic devices and microprocessor. Figure. 1: Categorization of the various Wireless Networking Standards BIB002  These technology is called software define radio (SDR). Cognitive Radio (CR) is further enhance as compared to SDR by employing software for measurement of the vacant portion of the wireless spectrum which is already there and operate that spectrum in a way that bound the interfering with other devices  . Licensed user is stated to be as a primary or key user in dynamic spectrum Access (DSA). The user who didn't have any licensed that got the permission for spectrum opportunistically is referred to as secondary user  . Cognitive Radio (CR) is more flexible and exposed to wireless network, if we compared with the typical radio networks. When the result of spectrum sensing in altered maliciously network activities which are normal will be disabled, even whole traffic may be broken down   . CR is the main technique which realizes DSA policy. CR first senses and identify the spectrum which is scanning a certain range of the spectrum to unoccupied spectrum. This methodology is used for the secondary user can determine that which spectrum can be used either radio or not.