Key management plays a very important role in the data communications environment. Problem The lack of security services, communication overhead, computation overhead, etc enables us to concentrate on creating new innovative ideas. A key distribution algorithm in the reviewed protocols doesn’t provide much security in group communication networks. Proposed SEGKMS proposes variable length user i...

In an olden research on sensor network security mainly considers homogeneous sensor networks, where all sensor nodes have the same capabilities. Research has shown that homogeneous ad hoc networks have poor performance and scalability. The many-to-one traffic pattern dominates in sensor networks, and hence a sensor may only communicate with a small portion of its neighbors. Most existing key ma...

W e present a new class of distributed key generation and recovery algorithms suitable f o r group communication syst ems where the group membership is either static or slowly time-varying, and m u s t be tightly controlled. The proposed key generation approach allows entities which m a y have only partial trust in each other t o jointly generate a shared key without the aid of a n external thi...

Medical management, is a team work and the nature of clinical toxicology is multidisciplinary. Internal organs problems following intoxications are included in field of internal medicine; similar problems in poisoned children brings pediatric medicine into the arena. The emergency nature of many acute intoxications, the legal problems of poisoned patients, respiratory assist in unconscious case...

We consider systems comprised of two interlacing M/M/ • /• type queues, where customers of each queue are the servers of the other queue. Such systems can be found for example in file sharing programs, SETI@home project, and other applications (see e.g. Arazi, Ben-Jacob and Yechiali (2005)). Denoting by Li the number of customers in queue i (Qi), i = 1, 2, we assume that Q1 is a multi-server fi...

We propose a protocol to transfer a one-time-pad (in a probabilistic manner) from Alice to Bob, over a public channel. The proposed protocol is unique because Bob merely acts as the receiver of the pad (secret key), i.e. Bob does not need to send any message back to Alice unless he detects eavesdropping. Such a secure transfer of one-time-pad, over public channel, is not possible in classical c...

Quantum secret-sharing protocols involving N partners (NQSS) are key distribution protocols in which Alice encodes her key into N − 1 qubits, in such a way that all the other partners must cooperate in order to retrieve the key. On these protocols, several eavesdropping scenarios are possible: some partners may want to reconstruct the key without the help of the other ones, and consequently col...

When one looks at commitment and encryption schemes, it is rather easy to spot the similarities between the two cryptographic notions. Although their functionalities are different and they are used for different purposes, they share a similar structure. Both encryptions and commitment make use of public keys, encryption schemes have an additional secret key. In both cases the secret hiding and ...

In this paper, information theoretic cryptography is discussed based on conditional Rényi entropies. Our discussion focuses not only on cryptography but also on the definitions of conditional Rényi entropies and the related information theoretic inequalities. First, we revisit conditional Rényi entropies, and clarify what kind of properties are required and actually satisfied. Then, we propose ...