Network forensic frameworks: Survey and research challenges

We construct two efficient Identity-Based Encryption (IBE) systems that admit selective-identity security reductions without random oracles in groups equipped with a bilinear map. Selective-identity secure IBE is a slightly weaker security model than the standard security model for IBE. In this model the adversary must commit ahead of time to the identity that it intends to attack, whereas in an adaptive-identity attack the adversary is allowed to choose this identity adaptively. Our first system—BB1—is based on the well studied decisional bilinear Diffie–Hellman assumption, and extends naturally to systems with hierarchical identities, or HIBE. Our second system—BB2—is based on a stronger assumption which we call the Bilinear Diffie–Hellman Inversion assumption and provides another approach to building IBE systems.

Our first system, BB1, is very versatile and well suited for practical applications: the basic hierarchical construction can be efficiently secured against chosen-ciphertext attacks, and further extended to support efficient non-interactive threshold decryption, among others, all without using random oracles. Both systems, BB1 and BB2, can be modified generically to provide “full” IBE security (i.e., against adaptive-identity attacks), either using random oracles, or in the standard model at the expense of a non-polynomial but easy-to-compensate security reduction.

Efficient selective identity-based encryption without random oracles

Security in mobile ad-hoc networks (MANETs) continues to attract attention after years of research. Recent advances in identity-based cryptography (IBC) sheds light on this problem and has become popular as a solution base. We present a comprehensive picture and capture the state of the art of IBC security applications in MANETs based on a survey of publications on this topic since the emergence of IBC in 2001. In this paper, we also share insights into open research problems and point out interesting future directions in this area.

A Survey of Applications of Identity-Based Cryptography in Mobile Ad-Hoc Networks

In this paper, we propose a new threshold attribute-based signcryption scheme secure in the standard model. The scheme provides message confidentiality, and authenticity of a message in addition to attesting the attributes of the sender. Such a property is useful in applications such as electronic card, digital prescription carrier devices, secure and authentic email service, etc. Our scheme relies on the intractability of the hashed modified decisional Diffie-Hellman and modified computational Diffie-Hellman assumptions, and is proven secure under adaptive chosen ciphertext attack and chosen message attack security notions of signcryption. Further, we achieve a tight reduction for both the security notions in the standard model.

Threshold attribute-based signcryption

Many recent key exchange (KE) protocols have been proven secure in the CK, CK-HMQV, or eCK security models. The exact relation between these security models, and hence the relation between the security guarantees provided by the protocols, is unclear. We show first that the CK, CK-HMQV, and eCK security models are formally incomparable. Second, we show that these models are also practically incomparable, by providing for each model attacks on protocols from the literature that are not considered by the other models. Third, our analysis enables us to find previously unreported flaws in protocol security proofs from the literature. We identify the causes of these flaws and show how they can be avoided.

Examining indistinguishability-based security models for key exchange protocols: the case of CK, CK-HMQV, and eCK

1College of Computer Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, China 2Centre for Computer and Information Security Research (CCISR), School of Computing and Information Technology, University of Wollongong, Wollongong, Australia 3School of Computer and Software, Nanjing University of Information Science, Nanjing, China ∗Corresponding author: wsusilo@uow.edu.au

A Key-Policy Attribute-Based Proxy Re-Encryption Without Random Oracles

Secure key issuing is an important issue in identity- based cryptography. At present there are some key issuing protocols in ID-based cryptography, but existent protocols are not applied due to centerless, self-organization, free move and other distinct characteristics of ad hoc network. In this paper, we propose an identity-based key issuing protocol for ad hoc networks, in which it makes use of the blind signature to ensure the secure issuing of the private key of the nodes in public channel. None of the nodes can impersonate the users to obtain the private keys. And the protocol, which suits ad hoc networks, is secure against replay, man-in-the-middle and insider attacks.

Identity-Based Key Issuing Protocol for Ad Hoc Networks

https://www.techscience.com/cmc/v66n3/41035/pdf

Long-term Preservation of Electronic Record Based on Digital Continuity in Smart Cities

Conditional proxy re-encryption allows a semi-trusted third-party proxy to convert Alice's ciphertext that meets a certain condition into another set of ciphertext. Meanwhile, the proxy cannot obtain any valuable information in the process. Nevertheless, a single re-encryption condition is difficult to meet the needs of practical applications, and the existing conditional proxy re-encryption scheme cannot flexibly control the conversion conditions. To solve this problem, this paper proposes a multi-conditional proxy broadcast re-encryption (MC-PBRE) scheme for file sharing systems. In our scheme, a single user can delegate the decryption rights of the encrypted file to a group of users. At the same time, users can set any number of conditions to control the user group decryption permissions. This paper demonstrates the security of the scheme for chosen-ciphertext attacks in the standard model. Furthermore, the program can resist collusion attacks, which means that the agent cannot collude with the user group to get the private key of the principal.

A CCA-secure multi-conditional proxy broadcast re-encryption scheme for cloud storage system

Weng et al. introduced the notion of conditional proxy re-encryption (C-PRE), whereby only the ciphertext satisfying one condition set by Alice can be re-encrypted by the proxy. To achieve more fine-grained delegation on the condition set, we introduce a new cryptographic primitive called fuzzy conditional proxy re-encryption (FC-PRE) in which we view conditions in C-PRE as a set of descriptive keywords. A FC-PRE scheme allows for a proxy with the re-encryption key for a conditional keyword set, W, to re-encrypt a ciphertext encrypted with a conditional keyword set, W′, if and only if W and W′ are close to each other as measured by the “set overlap” distance metric. Therefore, our system allows a certain amount of error-tolerance in the conditions. We formalize the FC-PRE security model by incorporating the advantages in previous C-PRE. Finally, we present an efficient construction of FC-PRE scheme, and prove its CCA-security under the well-studied decisional bilinear Diffie-Hellman (DBDH) assumption in the random oracle model.

Yongjun Ren

Papers

A Key-Policy Attribute-Based Proxy Re-Encryption Without Random Oracles

Identity-Based Key Issuing Protocol for Ad Hoc Networks

Long-term Preservation of Electronic Record Based on Digital Continuity in Smart Cities

A CCA-secure multi-conditional proxy broadcast re-encryption scheme for cloud storage system

Fuzzy conditional proxy re-encryption