In this paper, we propose a new provably secure cryptosystem for two party communication that provides security in the face of new technological breakthroughs. Most of the practical cryptosystems in use today can be breached in the future with new sophisticated methods. This jeopardizes the security of older but highly confidential messages. Our protocol is based on the bounded storage model first introduced in [1]. The protocol is secure as long as there is bound on the storage, however large it may be. We also suggest methods to extend the protocol to unbounded storage models where access to adversary is limited. Our protocol is a substantial improvement over previously known protocols and uses short key and optimal number of public random bits size of which is independent of message length. The smaller and constant length of key and public random string makes the scheme more practical. The protocol generates key using elements of the additive group $\mathbb{Z}_{\mathrm{n}}$ . Our protocol is very generalized and the protocol in [1] is a special case of our protocol. Our protocol is a step forward in making provably secure cryptosystems practical. An important open problem raised in [2] was designing an algorithm with short key and size of public random string $O(\mathcal{B})$ where $\mathcal{B}$ bounds the storage of adversary. Our protocol satisfies the conditions and is easy to implement.In this paper, we propose a new provably secure cryptosystem for two party communication that provides security in the face of new technological breakthroughs. Most of the practical cryptosystems in use today can be breached in the future with new sophisticated methods. This jeopardizes the security of older but highly confidential messages. Our protocol is based on the bounded storage model first introduced in [1]. The protocol is secure as long as there is bound on the storage, however large it may be. We also suggest methods to extend the protocol to unbounded storage models where access to adversary is limited. Our protocol is a substantial improvement over previously known protocols and uses short key and optimal number of public random bits size of which is independent of message length. The smaller and constant length of key and public random string makes the scheme more practical. The protocol generates key using elements of the additive group$\mathbb{Z}_{\mathrm{n}}$. Our protocol is very generalized and the protocol in [1] is a special case of our protocol. Our protocol is a step forward in making provably secure cryptosystems practical. An important open problem raised in [2] was designing an algorithm with short key and size of public random string$O(\mathcal{B})$where$\mathcal{B}$bounds the storage of adversary. Our protocol satisfies the conditions and is easy to implement.

GlobecomDec 1, 20210 citations

Secure Multiparty Computation in the Bounded Storage Model

Jiahui Liu, Satyanarayana Vusirikala

Lecture notes in computer scienceJan 1, 20212 citations

Information theoretically secure communication in the limited storage space model

Yonatan Aumann, Michael O. Rabin

Abstract. We provide a simple secret-key two-party secure communication scheme, which is provably information-theoretically secure in the limited-storage-space model. The limited-storage-space model postulates an eavesdropper who can execute arbitrarily complex computations, and is only limited in the total amount of storage space (not computation space) available to him. The bound on the storage space can be arbitrarily large (e.g. terabytes), as long as it is fixed. Given this bound, the protocol guarantees that the probability of the eavesdropper of gaining any information on the message is exponentially small. The proof of our main results utilizes a novel combination of linear algebra and Kolmogorov complexity considerations. 1Abstract. We provide a simple secret-key two-party secure communication scheme, which is provably information-theoretically secure in the limited-storage-space model. The limited-storage-space model postulates an eavesdropper who can execute arbitrarily complex computations, and is only limited in the total amount of storage space (not computation space) available to him. The bound on the storage space can be arbitrarily large (e.g. terabytes), as long as it is fixed. Given this bound, the protocol guarantees that the probability of the eavesdropper of gaining any information on the message is exponentially small. The proof of our main results utilizes a novel combination of linear algebra and Kolmogorov complexity considerations. 1

Jan 1, 19990 citations

Efficient Oblivious Transfer in the Bounded-Storage Model

Dowon Hong, Ku-Young Chang, Heuisu Ryu

Lecture notes in computer scienceJan 1, 200211 citations

Information Theoretically Secure Communication in the Limited Storage Space Model

Yonatan Aumann, Michael O. Rabin

Lecture notes in computer scienceJan 1, 199972 citations

Everlasting security in the bounded storage model

Yonatan Aumann, Yan Zong Ding, Michael O. Rabin

We address the problem of the-security of cryptographic protocols in face of future advances in computing technology and algorithmic research. The problem stems from the fact may be deemed that computations which at a given point in time may be deemed infeasible, can, in the course of years or decades, be made possible with improved hardware and/or breakthroughs in code-breaking algorithms. In such cases, the security of historical , but nonetheless highly confidential data may be in jeopardy. We present a scheme for efficient secure two-party communication with provable everlasting security. The security is guaranteed in face of any future technological advances, given the current state of of the art. Furthermore, the security of the messages is also guaranteed even if the secret encryption/decryption key is revealed in the future, The scheme is based on the bounded storage model and provides information-theoretic security in this model. The bounded storage model postulates an adversary who is computationally unbounded, and is only bounded in the amount of storage (not computation space) available to store the output of his computation. The bound on the storage can be arbitrarily large (e.g., 100 Tbytes), as long as it is fixed. Given this storage bound, our protocols guarantee that even a computationally all powerful adversary gains no information about a message (except with a probability that is exponentially small in the security parameter k). The bound on storage space need only hold at the time of the message transmission. Thereafter, no additional storage space or, computational power can help the adversary in deciphering the message. We present two protocols. The first protocol, which elaborates on the autoregressive (AR) protocol of Aumann and Rabin (see Advances in Cryptology-Crypto '99, p. 65-79, 1999), employs a short secret key whose size is independent of the length of the message, but uses many public random bits. The second protocol uses an optimal number of public random bits, but employs a longer secret key. Our proof of security utilizes a novel linear algebraic technique.We address the problem of the-security of cryptographic protocols in face of future advances in computing technology and algorithmic research. The problem stems from the fact may be deemed that computations which at a given point in time may be deemed infeasible, can, in the course of years or decades, be made possible with improved hardware and/or breakthroughs in code-breaking algorithms. In such cases, the security of historical , but nonetheless highly confidential data may be in jeopardy. We present a scheme for efficient secure two-party communication with provable everlasting security. The security is guaranteed in face of any future technological advances, given the current state of of the art. Furthermore, the security of the messages is also guaranteed even if the secret encryption/decryption key is revealed in the future, The scheme is based on the bounded storage model and provides information-theoretic security in this model. The bounded storage model postulates an adversary who is computationally unbounded, and is only bounded in the amount of storage (not computation space) available to store the output of his computation. The bound on the storage can be arbitrarily large (e.g., 100 Tbytes), as long as it is fixed. Given this storage bound, our protocols guarantee that even a computationally all powerful adversary gains no information about a message (except with a probability that is exponentially small in the security parameter k). The bound on storage space need only hold at the time of the message transmission. Thereafter, no additional storage space or, computational power can help the adversary in deciphering the message. We present two protocols. The first protocol, which elaborates on the autoregressive (AR) protocol of Aumann and Rabin (see Advances in Cryptology-Crypto '99, p. 65-79, 1999), employs a short secret key whose size is independent of the length of the message, but uses many public random bits. The second protocol uses an optimal number of public random bits, but employs a longer secret key. Our proof of security utilizes a novel linear algebraic technique.

IEEE Transactions on Information TheoryJun 1, 2002139 citations

\mathbb{Z}_{\mathrm{n}}

. Our protocol is very generalized and the protocol in [1] is a special case of our protocol. Our protocol is a step forward in making provably secure cryptosystems practical. An important open problem raised in [2] was designing an algorithm with short key and size of public random string

O(\mathcal{B})

where

\mathcal{B}

bounds the storage of adversary. Our protocol satisfies the conditions and is easy to implement.