Ubiquitous computing must incorporate a certain level of security. For the severely resource constrained applications, the energy-efficient and small size cryptography algorithm implementation is a critical problem. H...Ubiquitous computing must incorporate a certain level of security. For the severely resource constrained applications, the energy-efficient and small size cryptography algorithm implementation is a critical problem. Hardware implementations of the advanced encryption standard （AES） for authentication and encryption are presented. An energy consumption variable is derived to evaluate low-power design strategies for battery-powered devices. It proves that compact AES architectures fail to optimize the AES hardware energy, whereas reducing invalid switching activities and implementing power-optimized sub-modules are the reasonable methods. Implementations of different substitution box （S-Boxes） structures are presented with 0.25μm 1.8 V CMOS （complementary metal oxide semiconductor） standard cell library. The comparisons and trade-offs among area, security, and power are explored. The experimental results show that Galois field composite S-Boxes have smaller size and highest security but consume considerably more power, whereas decoder-switch-encoder S-Boxes have the best power characteristics with disadvantages in terms of size and security. The combination of these two type S-Boxes instead of homogeneous S-Boxes in AES circuit will lead to optimal schemes. The technique of latch-dividing data path is analyzed, and the quantitative simulation results demonstrate that this approach diminishes the glitches effectively at a very low hardware cost.展开更多
Pervasive computing has being now considered and noticed universally, which is the 21st century compute mode. This article first analyzes the origins of generating Mark Weiser's pervasive computing idea and the th...Pervasive computing has being now considered and noticed universally, which is the 21st century compute mode. This article first analyzes the origins of generating Mark Weiser's pervasive computing idea and the thrusts of researching it in the process of computing development. It then simply describes the pervasive computing projects of scientific research organizations of main developed countries, such as enterprise and universities, to realize Mark Weiser's idea. Next, it sketches a Layered Pervasive Computing (LPG) model and its related terms. Finally, the article closes with a discussion of great influence of pervasive computing technologies, and makes prospects of human being living environments such as economic, daily life, work, etc., according to the current development of computer hardware and software technologies and the evolvement of researching pervasive computing.展开更多
基金the "863" High Technology Research and Development Program of China (2006AA01Z226)the Scientific Research Foundation of Huazhong University of Science and Technology (2006Z011B)the Program for New Century Excellent Talents in University (NCET-07-0328).
文摘Ubiquitous computing must incorporate a certain level of security. For the severely resource constrained applications, the energy-efficient and small size cryptography algorithm implementation is a critical problem. Hardware implementations of the advanced encryption standard （AES） for authentication and encryption are presented. An energy consumption variable is derived to evaluate low-power design strategies for battery-powered devices. It proves that compact AES architectures fail to optimize the AES hardware energy, whereas reducing invalid switching activities and implementing power-optimized sub-modules are the reasonable methods. Implementations of different substitution box （S-Boxes） structures are presented with 0.25μm 1.8 V CMOS （complementary metal oxide semiconductor） standard cell library. The comparisons and trade-offs among area, security, and power are explored. The experimental results show that Galois field composite S-Boxes have smaller size and highest security but consume considerably more power, whereas decoder-switch-encoder S-Boxes have the best power characteristics with disadvantages in terms of size and security. The combination of these two type S-Boxes instead of homogeneous S-Boxes in AES circuit will lead to optimal schemes. The technique of latch-dividing data path is analyzed, and the quantitative simulation results demonstrate that this approach diminishes the glitches effectively at a very low hardware cost.
文摘Pervasive computing has being now considered and noticed universally, which is the 21st century compute mode. This article first analyzes the origins of generating Mark Weiser's pervasive computing idea and the thrusts of researching it in the process of computing development. It then simply describes the pervasive computing projects of scientific research organizations of main developed countries, such as enterprise and universities, to realize Mark Weiser's idea. Next, it sketches a Layered Pervasive Computing (LPG) model and its related terms. Finally, the article closes with a discussion of great influence of pervasive computing technologies, and makes prospects of human being living environments such as economic, daily life, work, etc., according to the current development of computer hardware and software technologies and the evolvement of researching pervasive computing.
基金the National High-Tech Research and Development Plan of China under Grant No.2006AA01Z198(国家高技术研究发展计划(863))the National Grand Fundamental Research 973 Program of China under Grant No.2005CB321800(国家重点基础研究发展规划(973))the National Science Fund of China for Distinguished Youth Scholar under Grant No.60625203(国家杰出青年科学基金).
