Self-healing Key Distribution Schemes with Sponsorization

Abstract

Abstract. In a self-healing key distribution scheme a group manager enables a large and dynamic group of users to establish a group key over an unreliable network. The group manager broadcasts in every session some packet of information in order to provide a common key to members of the session group. The goal of self-healing key distribution schemes is that, even if the broadcast is lost in a certain session, the group member can recover the key from the broadcast packets received before and after the session. This approach to key distribution is quite suitable for wireless networks, mobile wireless ad-hoc networks and in several Internet-related settings, where high security requirements need to be satisfied.In this work we provide a generalization of previous definitions in two aspects. The first one is to consider general structures instead of threshold ones to provide more flexible performance to the scheme. The second one is to consider the possibility that a coalition of users sponsor a user outside the group for one session: we give the formal definition of selfhealing key distribution schemes with sponsorization, some bounds on the required amount of information. We also give a general construction of a family of self-healing key distribution schemes with sponsorization by means of a linear secret sharing scheme. Our construction differs from previous self-healing key distribution schemes in the fact that the length of the broadcast is almost constant. Finally we analyze the particular case of this general construction when Shamir's secret sharing scheme is used.

An Authenticated Self-Healing Key Distribution Scheme Based on Bilinear Pairings

“…The three problems were inconsistent robustness, high overhead and expensive maintenance costs. Sáez in [4] considered the possibility that a coalition of users sponsor a user outside the group for one session. Muhammad et al in [5] considered the possibility of idea of mutual-healing.…”

“…Generally speaking, bilinear pairing computation is more time-consuming than scalar multiplication, let alone addition, hash and XOR operation. Therefore, the main computation overhead comes form (4).…”

Trade-off between collusion resistance and user life cycle in self-healing key distributions with t-revocation

“…However, these hash chain based constructions have the fatal defect of not being collusion resistant in the sense that the collusion between new joined users and the revoked users are able to recover all the session keys which they are not entitled to. Among the collusion resistance self-healing key distribution schemes [2], [3], [12], [13], [16], [17], only [17] is hash chain based and uses the same self-healing mechanism as introduced in [5]. We address the problem of achieving collusion resistance for [5] following the approach of [17], with better efficiency gains in computation and storage.…”

“…Further improvements in efficiency are obtained by relaxing the security slightly -from unconditional to computational [8], [5], [10]. The schemes [12], [13], [17] are based on vector space access structure instead of Shamir's [14] secret sharing. The hash chain based schemes [8], [5], [10] are computationally secure and are highly efficient compared to the existing unconditionally secure schemes.…”

“…Following the pioneering works by Staddon et al [15], a number of self-healing key distribution approaches are proposed [15], [9], [2], [3], [7], [11], [12], [13] to achieve unconditional security in formal generalized model with improved efficiency. Further improvements in efficiency are obtained by relaxing the security slightly -from unconditional to computational [8], [5], [10].…”