We present a quantum position verification scheme in the random oracle model. In contrast to prior work, our scheme does not require bounded storage/retrieval/entanglement assumptions. We also give an efficient position-based authentication protocol. This enables secret and authenticated communication with an entity that is only identified by its position in space.

Granboulan [4] proposed the signature scheme in the ideal cipher model named OPSSR that achieves the lower bound for message expansion. In this paper, we propose a scheme which can give the security equivalent to that of OPSSR in the random permutation model that is weaker than the ideal cipher model. We also show exact security proof. We extend our scheme to the multi key setting. By the resul...

A reasonably efficient password based key exchange (KE) protocol with provable security without random oracle was recently proposed by Katz, et al. [18] and later by Gennaro and Lindell [13]. However, these protocols do not support mutual authentication (MA). The authors explained that this could be achieved by adding an additional flow. But then this protocol turns out to be 4-round. As it is ...

A double length hash function is a 2n-bit hash function based on an n-bit compression function. To increase the security level, designs of good double length hash functions are important. In this paper we construct a class of maximally secure double length hash functions in random oracle model based on some good permutations. This class contains recently proposed double length hash functions [1...

Several generic constructions for transforming one-way functions to asymmetric encryption schemes have been proposed. One-way functions only guarantee the weak secrecy of their arguments. That is, given the image by a one-way function of a random value, an adversary has only negligible probability to compute this random value. Encryption schemes must guarantee a stronger secrecy notion. They mu...

We formalise the notion of adaptive proofs of knowledge in the random oracle model, where the extractor has to recover witnesses for multiple, possibly adaptively chosen statements and proofs. We also discuss extensions to simulation soundness, as typically required for the “encrypt-then-prove” construction of strongly secure encryption from IND-CPA schemes. Utilizing our model we show three re...

One of the main lines of research in functional encryption (FE) has consisted in studying the security notions for FE and their achievability. This study was initiated by [Boneh et al. – TCC’11, O’Neill – ePrint’10] where it was first shown that for FE the indistinguishabilitybased (IND) security notion is not sufficient in the sense that there are FE schemes that are provably IND-Secure but co...

Bennett and Gill (1981) showed that P 6= NP 6= coNP for a random oracle A, with probability 1. We investigate whether this result extends to individual polynomial-time random oracles. We consider two notions of random oracles: p-random oracles in the sense of martingales and resource-bounded measure (Lutz, 1992; Ambos-Spies et al., 1997), and p-betting-game random oracles using the betting game...

The Fiat-Shamir paradigm for transforming identification schemes into signature schemes has been popular since its introduction because it yields efficient signature schemes, and has been receiving renewed interest of late as the main tool in deriving forward-secure signature schemes. In this paper, minimal (meaning necessary and sufficient) conditions on the identification scheme to ensure sec...

The oracle problem is addressed for random testing and testing of randomized software. The presented Statistical Oracle is a Heuristic Oracle using statistical methods, especially statistical tests. The Statistical Oracle is applicable in case there are explicit formulae for the mean, the distribution, and so on, of characteristics computable from the test result. However, the present paper onl...