The Skynet 5 system will provide military satellite communications to all three UK armed services, and is to be procured as a ‘private finance initiative’ (PFI). Though there are many PFI projects across all parts of the public sector, this is the first time that such an approach has been taken for providing military satellite communications. On 26 February 2002, the Ministry of Defence announc...

Many applications of wireless sensor networks (WSNs) require deploying sensors in hostile environments, where an adversary may eavesdrop communications. To secure communications WSNs, the q-composite key predistribution scheme has been proposed literature. In this paper, we investigate k-connectivity WSNs operating under scheme, consideration unreliability links. Secure ensures that any two can...

In this paper we propose a comprehensive framework exploiting the polarization sensitive array (PLA) to improve the physical layer security of wireless communications. More specifically, the polarization difference among signals are utilized to improve the secrecy rate of wireless communications, especially when these signals are spatially indistinguishable. We firstly investigate the PLA based...

The market for Personal Digital Assistants (PDAs) is growing at a rapid pace. An increasing number of products, such as the PalmPilot, are adding wireless communications capabilities. PDA users are now able to send and receive email just as they would from their networked desktop machines. Because of the inherent insecurity of wireless environments, a system is needed for secure email communica...

Instant Messaging (IM) is a useful communication and work collaboration tool between individuals, groups, or enterprises. Unfortunately, most IM systems lack the needed security mechanism capable of ensuring the secure communications of IM client-client and IM client-server. In order to find a solution to secure IM communications, we designed and implemented a Secure Instant Messaging and Prese...