Mohammed Ashraful Alam Tuhin

Optimal secure message transmission by public discussion

In a secure message transmission (SMT) scenario, a sender wants to send a message in a private and reliable way to a receiver. Sender and receiver are connected by n wires, t of which can be controlled by an adaptive adversary with unlimited computational resources. In Eurocrypt 2008, Garay and Ostrovsky considered an SMT scenario where sender and receiver have access to a public discussion channel and showed that secure and reliable communication is possible when n ≥ t + 1. In this paper, we will show that a secure protocol requires at least three rounds of communication and two rounds invocation of the public channel and hence give a complete answer to the open question raised by Garay and Ostrovsky. We also describe a round optimal protocol that has constant transmission rate over the public channel.

A general construction for 1-round δ-RMT and (0, δ)-SMT

In Secure Message Transmission (SMT) problem, a sender

Optimal one round almost perfectly secure message transmission (short paper)

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Optimal message transmission protocols with flexible parameters

is connected to a receiver

Bounds and constructions for 1-round (0, δ)-secure message transmission against generalized adversary

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Efficient 1-Round Almost-Perfect Secure Message Transmission Protocols with Flexible Connectivity

through N node disjoint bidirectional paths in the network, t of which are controlled by an adversary with unlimited computational power.

(ε, 0)-Secure Message Transmission

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On Optimal Secure Message Transmission by Public Discussion

wants to send a message m to

Sanitization of Call Detail Records via Differentially-private Summaries

\cal{R}

New results on secure message transmission

in a reliable and private way. It is proved that SMT is possible if and only if N≥2t+1. In Reliable Message Transmission (RMT) problem, the network setting is the same and the goal is to provide reliability for communication, only. In this paper we focus on 1-round δ-RMT and (0,δ)-SMT where the chance of protocol failure (receiver cannot decode the sent message) is at most δ, and in the case of SMT, privacy is perfect. We propose a new approach to the construction of 1-round δ-RMT and (0, δ)-SMT for all connectivities N≥2t+1, using list decodable codes and message authentication codes. Our concrete constructions use folded Reed-Solomon codes and multireceiver message authentication codes. The protocols have optimal transmission rates and provide the highest reliability among all known comparable protocols. Important advantages of these constructions are, (i) they can be adapted to all connectivities, and (ii) have simple and direct security (privacy and reliability) proofs using properties of the underlying codes, and δ can be calculated from parameters of the underlying codes. We discuss our results in relation to previous work in this area and propose directions for future research.