487 research outputs found
Semantically Secure Anonymity: Foundations of Re-encryption
The notion of universal re-encryption is an established primitive
used in the design of many anonymity protocols. It allows anyone
to randomize a ciphertext without changing its size, without first
decrypting it, and without knowing who the receiver is (i.e., not
knowing the public key used to create it).
By design it prevents the randomized ciphertext from being
correlated with the original ciphertext.
We revisit and analyze the security
foundation of universal re-encryption and show a subtlety in it,
namely, that it does not require that the encryption function
achieve key anonymity. Recall that the encryption function is
different from the re-encryption function.
We demonstrate this subtlety by constructing a cryptosystem that satisfies the
established definition of a universal cryptosystem but that has an encryption
function that does not achieve key anonymity, thereby instantiating the gap in
the definition of security of universal re-encryption. We note that the
gap in the definition carries over to a set of applications
that rely on universal re-encryption, applications in the original
paper on universal re-encryption and also follow-on work.
This shows that the original definition needs to be corrected
and it shows that it had a knock-on
effect that negatively impacted security in later work.
We then introduce a new definition that includes
the properties that are needed for a re-encryption cryptosystem to achieve
key anonymity in both the encryption function and the re-encryption
function, building on Goldwasser and Micali\u27s semantic security and
the original key anonymity notion of Bellare, Boldyreva, Desai, and Pointcheval.
Omitting any of the properties in our definition leads to a problem.
We also introduce a new generalization of the Decision
Diffie-Hellman (DDH) random self-reduction and use it, in turn, to prove
that the original ElGamal-based universal cryptosystem of Golle et al
is secure under our revised security definition.
We apply our new DDH reduction
technique to give the first proof in the standard model that ElGamal-based
incomparable public keys achieve key anonymity under DDH.
We present a novel secure Forward-Anonymous Batch Mix
as a new application
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A Clean-Slate Design for the Next-Generation Secure Internet
This is the report on a workshop held at CMU on July 12-14, 2005. The workshop is part of the planning process initiated by NSF to explore potential architectures for a next generation secure network designed to meet the needs of the 21st century. In considering future architectures, we ignore issues of backward compatibility with the current Internet but seek to benefit from the experience gained by analyzing both the strengths and weaknesses of the current design. Specifically, this workshop looks at the fundamental interplay between security and underlying network architecture and seeks to chart a preliminary course for future work in this crucial research area. This workshop focused on initiating a productive dialog between experts from the network security and network architecture communities. The agenda was arranged to stimulate initial consideration of the security goals for a new Internet, the design space of possible solutions, how research in security and network architecture could be integrated so that security is included as a first-tier objective in future architectures, and to explore methods for identifying and considering the social consequences of these architecture and security design choices
Advances in Information Security and Privacy
With the recent pandemic emergency, many people are spending their days in smart working and have increased their use of digital resources for both work and entertainment. The result is that the amount of digital information handled online is dramatically increased, and we can observe a significant increase in the number of attacks, breaches, and hacks. This Special Issue aims to establish the state of the art in protecting information by mitigating information risks. This objective is reached by presenting both surveys on specific topics and original approaches and solutions to specific problems. In total, 16 papers have been published in this Special Issue
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ENABLING IOT AUTHENTICATION, PRIVACY AND SECURITY VIA BLOCKCHAIN
Although low-power and Internet-connected gadgets and sensors are increasingly integrated into our lives, the optimal design of these systems remains an issue. In particular, authentication, privacy, security, and performance are critical success factors. Furthermore, with emerging research areas such as autonomous cars, advanced manufacturing, smart cities, and building, usage of the Internet of Things (IoT) devices is expected to skyrocket. A single compromised node can be turned into a malicious one that brings down whole systems or causes disasters in safety-critical applications. This dissertation addresses the critical problems of (i) device management, (ii) data management, and (iii) service management in IoT systems. In particular, we propose an integrated platform solution for IoT device authentication, data privacy, and service security via blockchain-based smart contracts. We ensure IoT device authentication by blockchain-based IC traceability system, from its fabrication to its end-of-life, allowing both the supplier and a potential customer to verify an ICâs provenance. Results show that our proposed consortium blockchain framework implementation in Hyperledger Fabric for IC traceability achieves a throughput of 35 transactions per second (tps). To corroborate the blockchain information, we authenticate the IC securely and uniquely with an embedded Physically Unclonable Function (PUF). For reliable Weak PUF-based authentication, our proposed accelerated aging technique reduces the cumulative burn-in cost by ⌠56%. We also propose a blockchain-based solution to integrate the privacy of data generated from the IoT devices by giving users control of their privacy. The smart contract controlled trust-base ensures that the users have private access to their IoT devices and data. We then propose a remote configuration of IC features via smart contracts, where an IC can be programmed repeatedly and securely. This programmability will enable users to upgrade IC features or rent upgraded IC features for a fixed period after users have purchased the IC. We tailor the hardware to meet the blockchain performance. Our on-die hardware module design enforces the hardware configurationâs secure execution and uses only 2,844 slices in the Xilinx Zedboard Zynq Evaluation board. The blockchain framework facilitates decentralized IoT, where interacting devices are empowered to execute digital contracts autonomously
The Cryptographic Imagination
Originally published in 1996. In The Cryptographic Imagination, Shawn Rosenheim uses the writings of Edgar Allan Poe to pose a set of questions pertaining to literary genre, cultural modernity, and technology. Rosenheim argues that Poe's cryptographic writingâhis essays on cryptography and the short stories that grew out of themârequires that we rethink the relation of poststructural criticism to Poe's texts and, more generally, reconsider the relation of literature to communication. Cryptography serves not only as a template for the language, character, and themes of much of Poe's late fiction (including his creation, the detective story) but also as a "secret history" of literary modernity itself. "Both postwar fiction and literary criticism," the author writes, "are deeply indebted to the rise of cryptography in World War II." Still more surprising, in Rosenheim's view, Poe is not merely a source for such literary instances of cryptography as the codes in Conan Doyle's "The Dancing-Men" or in Jules Verne, but, through his effect on real cryptographers, Poe's writing influenced the outcome of World War II and the development of the Cold War. However unlikely such ideas sound, The Cryptographic Imagination offers compelling evidence that Poe's cryptographic writing clarifies one important avenue by which the twentieth century called itself into being. "The strength of Rosenheim's work extends to a revisionistic understanding of the entirety of literary history (as a repression of cryptography) and then, in a breathtaking shift of register, interlinks Poe's exercises in cryptography with the hyperreality of the CIA, the Cold War, and the Internet. What enables this extensive range of applications is the stipulated tension Rosenheim discerns in the relationship between the forms of the literary imagination and the condition of its mode of production. Cryptography, in this account, names the technology of literary productionâthe diacritical relationship between decoding and encodingâthat the literary imagination dissimulates as hieroglyphicsâthe hermeneutic relationship between a sign and its content."âDonald E. Pease, Dartmouth Colleg
Fingerprinting Encrypted Tunnel Endpoints
Operating System fingerprinting is a reconnaissance method used by Whitehats and Blackhats alike. Current techniques for fingerprinting do not take into account tunneling protocols, such as IPSec, SSL/TLS, and SSH, which effectively `wrap` network traffic in a ciphertext mantle, thus potentially rendering passive monitoring ineffectual. Whether encryption makes VPN tunnel endpoints immune to fingerprinting, or yields the encrypted contents of the VPN tunnel entirely indistinguishable, is a topic that has received modest coverage in academic literature. This study addresses these question by targeting two tunnelling protocols: IPSec and SSL/TLS. A new fingerprinting methodology is presented, several fingerprinting discriminants are identified, and test results are set forth, showing that endpoint identities can be uncovered, and that some of the contents of encrypted VPN tunnels can in fact be discerned.Dissertation (MSc (Computer Science))--University of Pretoria, 2005.Computer Scienceunrestricte
An Aesthetics of Hauntology
The text sets out to consider the aspects of the spectral, as proposed by Derrida in Spectres of Marx. As an alteric revenant refuting the historical/chronological determination of ratio and universality, it haunts the
architectonics of the metaphysical edifice. This spectral 'operation' is also an activity of encryption which
involves a discussion speculating on the virtual by proposing the transgressive rift as an introjective
interruption that is realised through the abysmal (dis)order of fenestration. It uncovers a thematic of topological (dis)location via a series of 'meridial threads' which the dissertation seeks to explore through a scrutiny of aesthetics and specific creative activities.
The first chapter explores this 'relation' with specific attention given to the alteric rift as an operation of differance as indicated by Derrida and seeks to critique this juxtaposition with particular reference and attention to Kant's aesthetics. Chapter two identifies Paul Celan's poem 'Todtnauberg' as a topos for a discussion on anticipation and silence in the complex historical relationship between the poet and the philosopher Martin Heidegger, as 'reported' in the poem. It identifies the topology of 'meridial haunting' at Heidegger's Black Forest mountain retreat. 'The Unheimlich Manoeuvre' (chapter three) deals with two key works by the architectural interventionist Gordon Matta-Clark, through a discussion on the uncanny (Unheimlich) and its relation to the homely (Heimlich), taking into account the encystic operation of mourning. The Final chapter continues this theme of the architecturally 'interruptive' by considering orientation with specific attention to the labyrinthine and the temporality of the crystal-image as cited by Deleuze
in his writings on cinema and the spectral. It looks specifically at two films by Tarkovsky; Solaris and Stalker
and Mark Z. Danelewski's novel House of Leaves (a complex fictitious account of a nonexistent documentary film which recounts the exploration of a labyrinth which appears in an ordinary suburban house)
A Console GRID Leveraged Authentication and Key Agreement Mechanism for LTE/SAE
Growing popularity of multimedia applications, pervasive connectivity, higher bandwidth, and euphoric technology penetration among bulk of the human race that happens to be cellular technology users, has fueled the adaptation to long-term evolution (LTE)/system architecture evolution. The LTE fulfills the resource demands of the next generation applications for now. We identify security issues in authentication mechanism used in LTE that without countermeasures might give super user rights to unauthorized users. The LTE uses static LTE key to derive the entire key hierarchy, i.e., LTE follows Evolved Packet SystemâAuthentication and Key Agreement based authentication, which discloses user identity, location, and other personally identifiable information. To counter this, we propose a public key cryptosystem named âInternational mobile subscriber identity Protected Console Grid based Authentication and Key Agreement (IPG-AKA) protocolâ to address the vulnerabilities related to weak key management. From the data obtained from threat modeling and simulation results, we claim that the IPG-AKA scheme not only improves security of authentication procedures, but also shows improvements in authentication loads and reduction in key generation time. The empirical results and qualitative analysis presented in this paper prove that IPG-AKA improves security in authentication procedure and performance in the LTE
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