Secure Message Transmission Using Centralized Group Key Distribution Protocol

Abstract

Abstract: In the secure message transmission, transmitted information can only receive by the authorized group members. To achieve a secure communication, symmetric key (group key) is used to both encrypt and decrypt the information, that shared among the group members. This paper, proposes an efficient centralized group key management scheme (GKDP) for achieving a secure multicast communication between the group members that reduces the cost of computation of SERVER(S) and rekeying cost of group members. The group key (GK) generated in the multicast network is securely distributed with the help of the RSA cryptosystem. Whenever the new member joins the group, computation cost of S reduced by performing single addition, multiplication and encryption, for updating the group key (GK). Whenever the member leaves the group, S performs single subtraction, division and encryption, for updating the group key (GK). By comparing with existing group key management protocol, the proposed protocol has significantly reduced computation complexity and rekeying cost. The proposed protocol is tested on star topology, the test results compared with existing group key management protocol. The comparison results show that the proposed protocol is efficient in terms of reducing the computational complexity of S and rekeying cost of group members. Index Terms: Secure multicast, rekeying cost, computational complexity, centralized group key management.