3 research outputs found

    The Design and Implementation of Scrambling Wavelength Hopping with AWG Router and Optical Switch over Secure WDM Network

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    In current experimental design, by exchanging the optical switch configured in front of arrayed waveguide grating (AWG) router, the wavelength hopping configuration was implemented over wavelength division multiplexing (WDM) network. In addition, in order to enhance the variable wavelength hopping pattern of proposed scheme, the transceiver oscillators were used to trigger the optical switch by a series of random and un-predictable electrical signal. The experiment results proved possible solution of secure WDM network that the wavelength hopping effect was monitored by optical spectrum analyzer (OSA) in optical domain. By using the oscilloscope for monitoring, the results showed the transmitted analogy signal of 10MHzwas extracted correctly by photo-detector while the wavelength hopping is happene

    Flexible Macroblock Ordering Scramble Encryption Techniques for H.264/AVC Videos

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    In this paper, a new video encryption method through scrambling the compressed videos is presented, which is targeted for H.264/AVC video encryptionin order to provide the greatest content protection in the compressed domain.The proposed algorithm uses a macroblock switching mechanism to scramble the video contentfor the compressed video sequences. Only the instantaneous decoded reference (IDR) pictures are scrambled to take the advantage of drift error propagation from all the inter-prediction frames. The proposed encryption technique is designed to perform after the encoding process on the compressed bitstream such that bitstream is modified by the parser directly. Finally,the scrambled video is still format-compliant to a general H.264/AVC decoder and can only be recovered by the authorized user that owns private key. Based on experimental results, the scene in the scrambled video can be effectively protected by the proposed scheme with low computational complexity and negligiblebitrate overhead

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

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    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 AnonymitĂ€t, die PrivatsphĂ€re und die Zensurfreiheit der Internetnutzer zu schĂŒtzen. 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 IdentitĂ€t der Tor-Nutzer und die Inhalte ihrer Nachrichten geheim halten, die Internetzensur kann dadurch nicht verhindert werden. Um die Netzwerksicherheit und insbesondere AnonymitĂ€t, PrivatsphĂ€re und IntegritĂ€t zusammen mit der VerfĂŒgbar.- und ZuverlĂ€ssigkeit von Netzwerkservices zu gewĂ€hrleisten, sind DiversitĂ€t, Zufallsprinzip, Codierung (auch VerschlĂŒsselung) 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 fĂŒr Kommunikationsnetze, die einen Schutz der AnonymitĂ€t und der PrivatsphĂ€re im Internet bei gleichzeitiger Sicherstellung von IntegritĂ€t, VerfĂŒgbarkeit und ZuverlĂ€ssigkeit ermöglichen. Die dabei verwendeten Konzepte sind die parallele DatenĂŒbertragung, das Random Routing, das Erasure Coding und redundante Systemkonfigurationen. Damit sollen DiversitĂ€t, Zufallsprinzip, Codierung und eine Überversorgung gewĂ€hrleistet werden. Da die entwickelten Übertragungssysteme komplexe Strukturen und Konfigurationen aufweisen, können existierende analytische Modelle nicht fĂŒr eine fundierte Bewertung angewendet werden. Daher ist der Schwerpunkt dieser Arbeit neue analytische Verfahren fĂŒr eine Bewertung von unterschiedlichen Netzwerkleistungsparametern, ZuverlĂ€ssigkeit und Security zu entwickeln und die Praxistauglichkeit der in der Arbeit aufgefĂŒhrten neuen Übertragungskonzepte zu beurteilen. Im Gegensatz zu existierenden ZuverlĂ€ssigkeitsmodellen berĂŒcksichtigt der analytische Ansatz dieser Arbeit die Vielfalt von beteiligten Netzwerkkomponenten, deren komplexe ZusammenhĂ€nge und AbhĂ€ngigkeiten im Fall eines Ausfalls
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