Non-Interactive Secure Multiparty Key Establishment

Abstract

Cryptographic schemes that provide establishment of secret keys among a number of participants are generally known as conference key establishment schemes and key broadcasting schemes. In any case, such protocols provide secure establishment of group-oriented cryptographic keys, but with the costs of multiple transmissions of key establishment messages and in some cases multiple secret user keys. In this paper, we present a simple and straightforward efficient non-interactive group-oriented key establishment scheme that provides off-line computation of secret group keys, without computations and transmissions of key establishment messages

Full-Resilient Memory-Optimum Multi-Party Non-Interactive Key Exchange

“…In 2014, Eskeland introduced a fully resilient and efficient MP-NIKE scheme based on modular exponentiation in RSA modulus [31]. Nevertheless, in this paper, we propose a Euclidean algorithm-based attack against this scheme, that invalidates Eskeland's claim.…”

“…C. ATTACK ON THE ESKELAND SCHEME Eskeland claimed that his scheme is fully resilient against any number of colluding adversaries [31]. The colluding adversaries have access to each other's private keys and also the shared key of the groups to which they belong.…”

“…Nevertheless, they do not have access to the master secret key of the KGC, nor to the private key of honest users (i.e. secrecy of private keys -Security Requirement-1 in [31]). However, we perform an attack by removing the effect of multipliers of ϕ(N ) and show how the secrecy of groups keys (Security Requirement-2 in [31]) is not guaranteed.…”

“…secrecy of private keys -Security Requirement-1 in [31]). However, we perform an attack by removing the effect of multipliers of ϕ(N ) and show how the secrecy of groups keys (Security Requirement-2 in [31]) is not guaranteed. Mathematically, we show this below: Let e i and e j be two public keys in the Eskeland scheme and gcd(e i , e j ) = 1.…”