Spectrum sharing security and attacks in CRNs: a review

Cognitive Radio plays a major part in communication technology by resolving the shortage of the spectrum through usage of dynamic spectrum access and artificial intelligence characteristics. The element of spectrum sharing in cognitive radio is a fundament al approach in utilising free channels. Cooperatively communicating cognitive radio devices use the common control channel of the cognitive radio medium access control to achieve spectrum sharing. Thus, the common control channel and consequently spectrum sharing security are vital to ensuring security in the subsequent data communication among cognitive radio nodes. In addition to well known security problems in wireless networks, cognitive radio networks introduce new classes of security threats and challenges, such as licensed user emulation attacks in spectrum sensing and misbehaviours in the common control channel transactions, which degrade the overall network operation and performance. This review paper briefly presents the known threats and attacks in wireless networks before it looks into the concept of cognitive radio and its main functionality. The paper then mainly focuses on spectrum sharing security and its related challenges. Since spectrum sharing is enabled through usage of the common control channel, more attention is paid to the security of the common control channel by looking into its security threats as well as protection and detection mechanisms. Finally, the pros and cons as well as the comparisons of different CR - specific security mechanisms are presented with some open research issues and challenges

A Careful Design for a Tool to Detect Child Pornography in P2P Networks

This paper addresses the social problem of child pornography on peer-to-peer (P2P) networks on the Internet and presents an automated system with effective computer and telematic tools for seeking out and identifying data exchanges with pedophilic content on the Internet. The paper analyzes the social and legal context in which the system must operate and describes the processes by which the system respects the rights of the persons investigated and prevents these tools from being used to establish processes of surveillance and attacks on the privacy of Internet users

What Next? The Quest to Protect Journalists and Human Rights Defenders in a Digital World

Around the world, governments and non-state actors are using sophisticated techniques to monitor, threaten, and harass human rights defenders (HRDs) and journalists. The growing use of digital technology has empowered activists to rally citizens around common causes and hold governments accountable, but it has also opened new doors for surveillance and harassment of activists and citizens' activities online. On November 14 -- 15, 2013, Freedom House, funded by the United States Agency for International Development (USAID), held a global conference in Mexico City entitled "What Next? The Quest to Protect Journalists and Human Rights Defenders in a Digital World," which brought together over 60 policymakers, donors, and activists to explore the full range of emerging threats and best strategies to overcome them; take an honest look at what is and is not working; and chart a path forward for more proactive and realistic solutions to build the resilience, sustainability, and relevance of HRDs and their movements. The conference sought to answer "what's next?" by identifying opportunities that can be exploited to build up frontline defenders and their ability to uphold human rights principles fearlessly and strategically at home and abroad