EÆcient hashing is a centerpiece of modern Cryptography. The progress in computing technology enables us to use 64-bit machines with the promise of 128bit machines in the near future. To exploit fully the technology for fast hashing, we need to be able to design cryptographically strong Boolean functions in many variables which can be evaluated faster using partial evaluations from the previous...

In today’s age of information technology secure transmission of information is a big challenge. Traditional symmetric and asymmetric methods are not suitable when the needed level of security is high. Hash function based systems are although better than traditional methods but are still inadequate in many cases due to their algorithmic complexity as they need the invertible functions to generat...

Security issues are the most challenging problems in cloud computing environments as an emerging technology. Regarding to this importance, an efficient and reliable user authentication and data protection model has been presented in this paper to increase the rate of reliability cloud-based environments. Accordingly, two encryption procedures have been established in an independent middleware (...

Recent measurements for Public Key Cryptography (PKC) protocols on 8-bit wireless sensor nodes showed optimistic results. It has been shown that Elliptic Curve Cryptography (ECC) is quite applicable to WSN. Still, PKC is much expensive in terms of computation and memory compared by the Symmetric Key Cryptography (SKC). In addition, in PKC, each public key needs to be authenticated before it’s u...

Chaos theory has been widely studied and adapted in cryptography for achieving some security mechanisms, such as encryption/decryption, key agreement and hash function. The privacy of using chaos cryptography mostly relies on one of or the combination of three mechanisms: (1) Universal construction symmetric cryptography; (2) Efficient type multiplication in finite field; (3) Prudent operation ...

In this paper, we study challenges and possible solutions to cryptographic key management in mission-critical networks. Existing symmetric key cryptography mechanisms do not scale well when supporting end-to-end secure and private communication. Existing public key cryptography mechanisms in self-organized ad hoc networks cannot resist a Sybil attack, where a single malicious node presents mult...

With continuous improvements in the efficiency of microelectronics, it is now possible to power a general-purpose microcontroller wirelessly at a reasonable range. Our implementation of RC5-32/12/16 on the WISP UHF RFID tag shows that conventional cryptography is no longer beyond the reach of a general-purpose UHF tag. In this paper, (1) we provide preliminary experimental data on how much comp...

We study the problems of testing isomorphism polynomials, algebras, and multilinear forms. Our first main results are average-case algorithms for these problems. For example, we develop an algorithm that takes two cubic forms $f, g\in \mathbb{F}_q[x_1,\dots, x_n]$, decides whether $f$ $g$ isomorphic in time $q^{O(n)}$ most $f$. This setting has direct practical implications, having been studied...