Secure group communication in mobile ad hoc networks is often dynamic and impromptu, and thus requires efficient and automated secure group management and seamless combination of secure groups with distributed applications running upon them. Existing approaches to secure group communication cannot satisfy these requirements. In this paper, an automated secure group management approach is presen...

We translate the problem of designing a secure communications protocol for several users communicating through a relay in a wireless network into understanding certain subvarieties of products of Grassmannians. We calculate the dimension of these subvarieties and provide various results concerning their defining equations. When the relay and all of the users have the same number of antennas, th...

Many linear and nonlinear control methods have been employed to control chaos. In practical applications the investigators would like to use simple and efficient controllers. The design of the simplest controller is an open problem yet. In this paper we applied MasterSlave Synchronization to the chaotic Sprott’s circuits. These circuits may have practical application in secure communications be...

A new chaotic communication scheme using sliding-mode adaptive observer is presented. Using synchronization in conjunction with digital communication schemes, we have enhanced the security of the transmitted signal and achieved a satisfactory, typical, secure communication scheme. The proposed system requires only one observer, which is an advantage over some of related work in this area. The s...

Two major issues are considered in this paper: security of communication and reliability of connection. The paper demonstrates how to interlink both the security requirement and communication assurance into one algorithmic procedure. Several reliability protocols are described and their characteristics (probabilities of failure, bandwidth requirement per block of transmitted ciphertext and comp...

The MIMOME channel is a Gaussian wiretap channel in which the sender, receiver, and eavesdropper all have multiple antennas. We characterize the secrecy capacity as the saddle-value of a minimax problem. Among other implications, our result establishes that a Gaussian distribution maximizes the secrecy capacity characterization of Csiszár and Körner when applied to the MIMOME channel. We also d...