Optimistic fair exchange (OFE) is a protocol for solving the problem of exchanging items or services in a fair manner between two parties, a signer and a verifier, with the help of an arbitrator which is called in only when a dispute happens between the two parties. In almost all the previous work on OFE, after obtaining a partial signature from the signer, the verifier can present it to others...

We introduce the first secure Certificateless Public Key Encryption (CL-PKE) scheme against a malicious Key Generation Center (KGC) in the standard model. Recently, Au et al. [3] pointed out that the previous security models for CL-PKE schemes cannot guarantee the security against a malicious KGC. They also showed that although some schemes are secure against malicious KGC, they require the ran...

Wireless Sensor Networks (WSN) usually consists of a large number of tiny sensors with limited computation capability, memory space and power resource. WSN’s are extremely vulnerable against any kind of internal or external attacks, due to several factors such as resource constrained nodes and lack of tamperresistant packages. To achieve security in Wireless Sensor Networks, it is important to ...

We propose a probabilistic key predistribution scheme for wireless sensor networks, where keying materials are distributed to sensor nodes for secure communication. We use a two-tier approach in which there are two types of nodes: regular nodes and agent nodes. Agent nodes are more capable than regular nodes. Our node deployment model is zone-based such that the nodes that may end up with close...

In the last decade, we witness a proliferation of potential application domains of wireless sensor networks (WSN). Therefore, a host of research works have been conducted by both academic and industrial communities. Nevertheless, given the sensitivity of the potential applications that are generally tightly related to the physical world and may be human beings, a large scale deployment of WSN d...

In near future, the Wireless Sensor Networks (WSN) is widely used in many applications like military and civil domains. The wireless sensor networks are always deployed in hostile and pervasive environment. Security is major concern in the wireless sensor network. The traditional network security methods are not suitable for wireless sensor networks because of limited resource. Several Key mana...

This study introduces a method for generating a particular permutation P of a given size N out of N! permutations from a given key. This method computes a unique permutation for a specific size since it takes the same key; therefore, the same permutation can be computed each time the same key and size are applied. The name of random permutation comes from the fact that the probability of gettin...