A Block Compressive Sensing Based Scalable Encryption Framework for Protecting Significant Image Regions

The existing Block Compressive Sensing (BCS) based image ciphers adopted the same sampling rate for all the blocks, which may lead to the desirable result that after subsampling, significant blocks lose some more-useful information while insignificant blocks still retain some less-useful information. Motivated by this observation, we propose a scalable encryption framework (SEF) based on BCS together with a Sobel Edge Detector and Cascade Chaotic Maps. Our work is firstly dedicated to the design of two new fusion techniques, chaos-based structurally random matrices and chaos-based random convolution and subsampling. The basic idea is to divide an image into some blocks with an equal size and then diagnose their respective significance with the help of the Sobel Edge Detector. For significant block encryption, chaos-based structurally random matrix is applied to significant blocks whereas chaos-based random convolution and subsampling are responsible for the remaining insignificant ones. In comparison with the BCS based image ciphers, the SEF takes lightweight subsampling and severe sensitivity encryption for the significant blocks and severe subsampling and lightweight robustness encryption for the insignificant ones in parallel, thus better protecting significant image regions.

A Lightweight Authentication Protocol for Secure Communications between Resource-Limited Devices and Wireless Sensor Networks

The number of Resource-Limited Wireless Devices utilized in many areas of IT is growing rapidly. Some of the applications of these devices pose real security threats that can be addressed using authentication and cryptography. Many of the available authentication and encryption software solutions are predicated on the availability of ample processing power and memory. These demands cannot be met by the majority of ubiquitous computing devices, thus there is a need to apply lightweight cryptography primitives and lightweight authentication protocols that meet these demands in any application of security to devices with limited resources. A security framework is presented here that combines aspects of the Gossamer protocol and the Scalable Encryption Algorithm (SEA) to provide an implementation of inter-device security. The Gossamer Protocol is additionally used as a means of exchanging session keys for use with the SEA encryption protocol. Our system performed well with the code space requirements smaller than 600 bytes (excluding shared libraries) and a performance of 27 milliseconds per one 96-bit block of data.