HIDING CRIMES IN CYBERSPACE

Criminals have at their disposal a variety of technologies for hiding communications and evidence stored on computers from law enforcement. These include encryption, passwords, digital compression, steganography, remote storage, and audit disabling. They can also hide crimes through anonymity tools and techniques such as anonymous remailers, anonymous digital cash, looping, cloned cellular phones, and cellular phone cards. This paper discusses use of these technologies by criminals and terrorists, and how that use has affected investigations and prosecutions. Options available to law enforcement for dealing with the technologies, especially encryption, are also discussed. Numerous case studies are presented for illustration.     

一种新的基于FPGA的加密技术

介绍和讨论基于FPGA的硬件技术实现分组加密算法时所采用的4种结构及其性能.同时对5种AES侯选算法的软件实现和FPGA实现的结果和性能进行比较分析.     

史前城市的考古新发现与中国文明的起源

近十多年来考古新发现的五十多座史前城址不是中国五六千年文明史的证据，而是中国文明漫长起源期的历史反映。仰韶时代的初现的城市代表了中国文明的萌芽与奠基，龙山时代繁盛的城市是文明即将诞生的标志。夏以前的中国不是文明社会