A Practical and Flexible Key Management Mechanism For Trusted Collaborative Computing

Trusted collaborative computing (TCC) is a new research and application paradigm. Two important challenges in such a context are represented by secure information transmission among the collaborating parties and selective differentiated access to data among members of collaborating groups. Addressing such challenges requires, among other things, developing techniques for secure group communication (SGQ), secure dynamic conferencing (SDC), differential access control (DIF-AC), and hierarchical access control (HAC). Cryptography and key management have been intensively investigated and widely applied in order to secure information. However, there is a lack of key management mechanisms which are general and flexible enough to address all requirements arising from information transmission and data access. This paper proposes the first holistic group key management scheme which can directly support all these functions yet retain efficiency. The proposed scheme is based on the innovative concept of access control polynomial (ACP) that can efficiently and effectively support full dynamics, flexible access control with fine-tuned granularity, and anonymity. The new scheme is immune from various attacks from both external and internal malicious parties.

I. Introduction

Information and communication technologies along with society's drive for collaboration in the modern world make “collaborative computing” (CC) and its applications possible and necessary. Typical CC applications include, but not limited to, multi-party military actions, tele-conferencing, tele-medicine, interactive and collaborative decision making, grid-computing, information distribution, and pay per view services. Trust in such environment can eventually determine its success and popularity due to people's desire for confidentiality, privacy and integrity of their personal and/or corporate information. The current Internet by design does not provide high assurance security for data transmission [1], [2]. Compared to the two-party interaction model (such as the client-server service model), CC environments are group-oriented, involve a large number of entities and shared resources, are complex, dynamic, distributed, and heterogeneous and may possibly include hostile elements. Systems experience failures due to intrusions and attacks from hostile entities [3], [4]. In addition, there is the problem of insider threats, by which attacks are from malicious parties inside the organizations or members of CC groups. Consequently, building a trusted collaborative computing (TCC) environment is very difficult and requires a long term persevering endeavor.