A Survey on Wireless Security: Technical Challenges, Recent Advances and Future Trends

This paper examines the security vulnerabilities and threats imposed by the inherent open nature of wireless communications and to devise efficient defense mechanisms for improving the wireless network security. We first summarize the security requirements of wireless networks, including their authenticity, confidentiality, integrity and availability issues. Next, a comprehensive overview of security attacks encountered in wireless networks is presented in view of the network protocol architecture, where the potential security threats are discussed at each protocol layer. We also provide a survey of the existing security protocols and algorithms that are adopted in the existing wireless network standards, such as the Bluetooth, Wi-Fi, WiMAX, and the long-term evolution (LTE) systems. Then, we discuss the state-of-the-art in physical-layer security, which is an emerging technique of securing the open communications environment against eavesdropping attacks at the physical layer. We also introduce the family of various jamming attacks and their counter-measures, including the constant jammer, intermittent jammer, reactive jammer, adaptive jammer and intelligent jammer. Additionally, we discuss the integration of physical-layer security into existing authentication and cryptography mechanisms for further securing wireless networks. Finally, some technical challenges which remain unresolved at the time of writing are summarized and the future trends in wireless security are discussed.Comment: 36 pages. Accepted to Appear in Proceedings of the IEEE, 201

Ein analytisches Framework zur Bewertung der Zuverlässigkeit und Security von fortschrittlichen Netzwerk Systemen

Today, anonymous networks such as The Onion Routing (Tor) have been designed to ensure anonymity, privacy and censorship prevention, which have become major concerns in modern society. Although the Tor network provides layered encryption and traffic tunneling against eavesdropping attacks, the jamming attacks and their impact on the network and network services can not be efficiently handled today. Moreover, to defy modern censorship, it is not enough just to use the Tor network to hide the client's identity and the message content as the censorship has become a type of jamming attack, which prevents users from connecting to the censored network nodes by blocking or jamming (Tor) traffic. In network security, the main tools to protect privacy and anonymity as well as integrity and service reliability against eavesdropping and jamming, respectively, are diversity, randomness, coding or encryption and over-provisioning, all less exploit in traditional networks. This thesis provides radical new network concepts to address the needs of traditional networks for privacy, anonymity, integrity, and reliability; and designs \emph{advanced network systems} based on parallel transmission, random routing, erasure coding and redundant configurations as tools to offer diversity, randomness, coding and over-provisioning. Since the network systems designed in this thesis can not be evaluated with existing analytical models due to their rather complex configurations, the main focus of this work is a development of novel analytical approaches for evaluation of network performance, reliability and security of these systems and to show their practicality. The provided analysis is based on combinatorics, probability and information theory. In contrast to current reliability models, the analysis in this thesis takes into account the sharing of network components, heterogeneity of software and hardware, and interdependence between failed components. The significant property of the new security analysis proposed is the ability to assess the level of privacy, anonymity, integrity and censorship success when multiple jamming and eavesdropping adversaries reside in the network.Derzeit werden anonyme Internet Kommunikationssysteme, wie The Onion Routing (Tor), verwendet, um die Anonymität, die Privatsphäre und die Zensurfreiheit der Internetnutzer zu schützen. Obwohl das Tor-Netzwerk einen Schutz vor Lauschangriffe (Eavesdropping) bietet, kann ein beabsichtigtes Stören (Jamming) der Übertragung und den daraus resultierenden Auswirkungen auf die Netzwerkfunktionen derzeit nicht effektiv abgewehrt werden. Auch das moderne Zensurverfahren im Internet stellt eine Art des Jammings dar. Deswegen kann das Tor Netzwerk zwar die Identität der Tor-Nutzer und die Inhalte ihrer Nachrichten geheim halten, die Internetzensur kann dadurch nicht verhindert werden. Um die Netzwerksicherheit und insbesondere Anonymität, Privatsphäre und Integrität zusammen mit der Verfügbar.- und Zuverlässigkeit von Netzwerkservices zu gewährleisten, sind Diversität, Zufallsprinzip, Codierung (auch Verschlüsselung) und eine Überversorgung, die in den konventionellen Netzwerksystemen eher sparsam angewendet werden, die wichtigsten Mittel gegen Security-Angriffe. Diese Arbeit befasst sich mit grundlegend neuen Konzepten für Kommunikationsnetze, die einen Schutz der Anonymität und der Privatsphäre im Internet bei gleichzeitiger Sicherstellung von Integrität, Verfügbarkeit und Zuverlässigkeit ermöglichen. Die dabei verwendeten Konzepte sind die parallele Datenübertragung, das Random Routing, das Erasure Coding und redundante Systemkonfigurationen. Damit sollen Diversität, Zufallsprinzip, Codierung und eine Überversorgung gewährleistet werden. Da die entwickelten Übertragungssysteme komplexe Strukturen und Konfigurationen aufweisen, können existierende analytische Modelle nicht für eine fundierte Bewertung angewendet werden. Daher ist der Schwerpunkt dieser Arbeit neue analytische Verfahren für eine Bewertung von unterschiedlichen Netzwerkleistungsparametern, Zuverlässigkeit und Security zu entwickeln und die Praxistauglichkeit der in der Arbeit aufgeführten neuen Übertragungskonzepte zu beurteilen. Im Gegensatz zu existierenden Zuverlässigkeitsmodellen berücksichtigt der analytische Ansatz dieser Arbeit die Vielfalt von beteiligten Netzwerkkomponenten, deren komplexe Zusammenhänge und Abhängigkeiten im Fall eines Ausfalls

NEMESYS: Enhanced Network Security for Seamless Service Provisioning in the Smart Mobile Ecosystem

As a consequence of the growing popularity of smart mobile devices, mobile malware is clearly on the rise, with attackers targeting valuable user information and exploiting vulnerabilities of the mobile ecosystems. With the emergence of large-scale mobile botnets, smartphones can also be used to launch attacks on mobile networks. The NEMESYS project will develop novel security technologies for seamless service provisioning in the smart mobile ecosystem, and improve mobile network security through better understanding of the threat landscape. NEMESYS will gather and analyze information about the nature of cyber-attacks targeting mobile users and the mobile network so that appropriate counter-measures can be taken. We will develop a data collection infrastructure that incorporates virtualized mobile honeypots and a honeyclient, to gather, detect and provide early warning of mobile attacks and better understand the modus operandi of cyber-criminals that target mobile devices. By correlating the extracted information with the known patterns of attacks from wireline networks, we will reveal and identify trends in the way that cyber-criminals launch attacks against mobile devices.Comment: Accepted for publication in Proceedings of the 28th International Symposium on Computer and Information Sciences (ISCIS'13); 9 pages; 1 figur

Lawful Hacking: Using Existing Vulnerabilities for Wiretapping on the Internet

For years, legal wiretapping was straightforward: the officer doing the intercept connected a tape recorder or the like to a single pair of wires. By the 1990s, however, the changing structure of telecommunications—there was no longer just “Ma Bell” to talk to—and new technologies such as ISDN and cellular telephony made executing a wiretap more complicated for law enforcement. Simple technologies would no longer suffice. In response, Congress passed the Communications Assistance for Law Enforcement Act (CALEA) which mandated a standardized lawful intercept interface on all local phone switches. Since its passage, technology has continued to progress, and in the face of new forms of communication—Skype, voice chat during multiplayer online games, instant messaging, etc.—law enforcement is again experiencing problems. The FBI has called this “Going Dark”: their loss of access to suspects’ communication. According to news reports, law enforcement wants changes to the wiretap laws to require a CALEA-like interface in Internet software. CALEA, though, has its own issues: it is complex software specifically intended to create a security hole—eavesdropping capability—in the already-complex environment of a phone switch. It has unfortunately made wiretapping easier for everyone, not just law enforcement. Congress failed to heed experts’ warnings of the danger posed by this mandated vulnerability, and time has proven the experts right. The so-called “Athens Affair,” where someone used the built-in lawful intercept mechanism to listen to the cell phone calls of high Greek officials, including the Prime Minister, is but one example. In an earlier work, we showed why extending CALEA to the Internet would create very serious problems, including the security problems it has visited on the phone system. In this paper, we explore the viability and implications of an alternative method for addressing law enforcements need to access communications: legalized hacking of target devices through existing vulnerabilities in end-user software and platforms. The FBI already uses this approach on a small scale; we expect that its use will increase, especially as centralized wiretapping capabilities become less viable. Relying on vulnerabilities and hacking poses a large set of legal and policy questions, some practical and some normative. Among these are: (1) Will it create disincentives to patching? (2) Will there be a negative effect on innovation? (Lessons from the so-called “Crypto Wars” of the 1990s, and in particular the debate over export controls on cryptography, are instructive here.) (3) Will law enforcement’s participation in vulnerabilities purchasing skew the market? (4) Do local and even state law enforcement agencies have the technical sophistication to develop and use exploits? If not, how should this be handled? A larger FBI role? (5) Should law enforcement even be participating in a market where many of the sellers and other buyers are themselves criminals? (6) What happens if these tools are captured and repurposed by miscreants? (7) Should we sanction otherwise illegal network activity to aid law enforcement? (8) Is the probability of success from such an approach too low for it to be useful? As we will show, these issues are indeed challenging. We regard the issues raised by using vulnerabilities as, on balance, preferable to adding more complexity and insecurity to online systems

Security performance and protocol consideration in optical communication system with optical layer security enabled by optical coding techniques

With the fast development of communication systems, network security issues have more and more impact on daily life. It is essential to construct a high degree of optical layer security to resolve the security problem once and for all. Three different techniques which can provide optical layer security are introduced and compared. Optical chaos can be used for fast random number generation. Quantum cryptography is the most promising technique for key distribution. And the optical coding techniques can be deployed to encrypt the modulated signal in the optical layer. A mathematical equation has been derived from information theory to evaluate the information-theoretic security level of the wiretap channel in optical coding schemes. And the merits and limitation of two coherent optical coding schemes, temporal phase coding and spectral phase coding, have been analysed. The security scheme based on a reconfigurable optical coding device has been introduced, and the corresponding security protocol has been developed. By moving the encryption operation from the electronic layer to the optical layer, the modulated signals become opaque to the unauthorised users. Optical code distribution and authentication is the one of the major challenges for our proposed scheme. In our proposed protocol, both of the operations are covered and defined in detail. As a preliminary draft of the optical code security protocol, it could be a useful guidance for further research

The Eavesdropper\u27s Dilemma

This paper examines the problem of surreptitious Internet interception from the eavesdropper\u27s point of view. We introduce the notion of fidelity in digital eavesdropping. In particular, we formalize several kinds of network noise that might degrade fidelity, most notably confusion, and show that reliable network interception may not be as simple as previously thought or even always possible. Finally, we suggest requirements for high fidelity network interception, and show how systems that do not meet these requirements can be vulnerable to countermeasures, which in some cases can be performed entirely by a third party without the cooperation or even knowledge of the communicating parties

Privacy and Security in the Cloud: Some Realism About Technical Solutions to Transnational Surveillance in the Post-Snowden Era

Since June 2013, the leak of thousands of classified documents regarding highly sensitive U.S. surveillance activities by former National Security Agency (NSA) contractor Edward Snowden has greatly intensified discussions of privacy, trust, and freedom in relation to the use of global computing and communication services. This is happening during a period of ongoing transition to cloud computing services by organizations, businesses, and individuals. There has always been a question of inherent in this transition: are cloud services sufficiently able to guarantee the security of their customers’ data as well s the proper restrictions on access by third parties, including governments? While worries over government access to data in the cloud is a predominate part of the ongoing debate over the use of cloud serives, the Snowden revelations highlight that intelligence agency operations pose a unique threat to the ability of services to keep their customers’ data out of the hands of domestic as well as foreign governments. The search for a proper response is ongoing, from the perspective of market players, governments, and civil society. At the technical and organizational level, industry players are responding with the wider and more sophisticated deployment of encryption as well as a new emphasis on the use of privacy enhancing technologies and innovative architectures for securing their services. These responses are the focus of this Article, which contributes to the discussion of transnational surveillance by looking at the interaction between the relevant legal frameworks on the one hand, and the possible technical and organizational responses of cloud service providers to such surveillance on the other. While the Article’s aim is to contribute to the debate about government surveillance with respect to cloud services in particular, much of the discussion is relevant for Internet services more broadly

Practical Traffic Analysis Attacks on Secure Messaging Applications

Instant Messaging (IM) applications like Telegram, Signal, and WhatsApp have become extremely popular in recent years. Unfortunately, such IM services have been targets of continuous governmental surveillance and censorship, as these services are home to public and private communication channels on socially and politically sensitive topics. To protect their clients, popular IM services deploy state-of-the-art encryption mechanisms. In this paper, we show that despite the use of advanced encryption, popular IM applications leak sensitive information about their clients to adversaries who merely monitor their encrypted IM traffic, with no need for leveraging any software vulnerabilities of IM applications. Specifically, we devise traffic analysis attacks that enable an adversary to identify administrators as well as members of target IM channels (e.g., forums) with high accuracies. We believe that our study demonstrates a significant, real-world threat to the users of such services given the increasing attempts by oppressive governments at cracking down controversial IM channels. We demonstrate the practicality of our traffic analysis attacks through extensive experiments on real-world IM communications. We show that standard countermeasure techniques such as adding cover traffic can degrade the effectiveness of the attacks we introduce in this paper. We hope that our study will encourage IM providers to integrate effective traffic obfuscation countermeasures into their software. In the meantime, we have designed and deployed an open-source, publicly available countermeasure system, called IMProxy, that can be used by IM clients with no need for any support from IM providers. We have demonstrated the effectiveness of IMProxy through experiments

Will Wi-Fi Make Your Private Network Public? Wardriving, Criminal and Civil Liability, and the Security Risks of Wireless Networks

Wireless networking is growing in popularity because it is often cheaper and more convenient than other computer networking systems. Wireless networks, however, are also very hard to secure. Locating insecure wireless networks and advertising their locations is an activity known as “wardriving.” Exploiting the vulnerability of a wireless network to hack into the computer system or to monitor the wireless transmissions can give rise to liability under federal felony and misdemeanor statutes, as well as federal civil liability and liability under state law private causes of action. When introducing wireless networking into business information systems, system administrators should use all possible care to secure the network, and IT policies and practices should be updated to make sure that wireless networking risks that cannot be eliminated through technology are managed prudently

Security for correlated sources across wiretap network

A thesis submitted in ful llment of the requirements for the degree of Doctor of Philosophy in the School of Electrical and Information Engineering Faculty of Engineering University of the Witwatersrand July 2015This thesis presents research conducted for the security aspects of correlated sources across a wiretap network. Correlated sources are present in communication systems where protocols ensure that there is some predetermined information for sources to transmit. Systems that contain correlated sources are for example broadcast channels, smart grid systems, wireless sensor networks and social media networks. In these systems there exist common information between the nodes in a network, which gives rise to security risks as common information can be determined about more than one source. In this work the security aspects of correlated sources are investigated. Correlated source coding in terms of the Slepian-Wolf theorem is investigated to determine the amount of information leakage for various correlated source models. The perfect secrecy approach developed by Shannon has also been incorporated as a security approach. In order to explore these security aspects the techniques employed range from typical sequences used to prove Slepian-Wolf's theorem to coding methods incorporating matrix partitions for correlated sources. A generalized correlated source model is presented and the procedure to determine the information leakage is initially illustrated using this model. A novel scenario for two correlated sources across a channel with eavesdroppers is also investigated. It is a basic model catering for the correlated source applications that have been detailed. The information leakage quanti cation is provided, where bounds specify the quantity of information leaked for various cases of eavesdropped channel information. The required transmission rates for perfect secrecy when some channel information has been wiretapped is further determined, followed by a method to reduce the key length required for perfect secrecy. The implementation thereafter provided shows how the information leakage is determined practically. In the same way using the information leakage quanti cation, Shannon's cipher system approach and practical implementation a novel two correlated source model where channel information and some source data symbols (predetermined information) are wiretapped is investigated. The adversary in this situation has access to more information than if a link is wiretapped only and can thus determine more about a particular source. This scenario caters for an application where the eavesdropper has access to some predetermined information. The security aspects and coding implementation have further been developed for a novel correlated source model with a heterogeneous encoding method. The model caters for situations where a wiretapper is able to easily access a particular source. iii The interesting link between information theory and coding theory is explored for the novel models presented in this research. A matrix partition method is utilized and the information leakage for various cases of wiretapped syndromes are presented. The research explores the security for correlated sources in the presence of wiretappers. Both the information leakage and Shannon's cipher system approach are used to achieve these security aspects. The implementation shows the practicality of using these security aspects in communications systems. The research contained herein is signi cant as evident from the various applications it may be used for and to the author's knowledge is novel