Accounting Office (GAO) disclosed that approximately 250,000 break-ins into Federal computer systems were attempted over the previous year. At least 10 major agencies, comprising 98% of the total Federal budget, had been attacked. The GAO went on to say that an estimated 64% of these attacks (about 160,000) were successful. It gets worse: the number of… (More)
—We describe RapidUpdate, a peer-assisted system tailored to the specific needs of distributing security content. Its unique features include being able to distribute small files while still offloading a vast majority of the distribution bandwidth, using central planning in order to maximize efficiency and meet distribution deadlines, and allowing peers to… (More)
Spam and phishing emails are not only annoying to users, but are a real threat to inter-net communication and web economy. The fight against unwanted emails has become a cat-and-mouse game between criminals and people trying to develop techniques for detecting such unwanted emails. Criminals are constantly developing new tricks and adopt the ones that make… (More)
Official policies for controlling access to classified information in the U.S. are quite complex and often difficult to enforce. We present an encoding of a common core of these policies in an authorization logic, and describe their rigorous enforcement in PCFS, a file system implemented for such purposes.
We propose an architecture of four complimentary technologies increasingly relevant to a growing number of home users and organizations: cryptography, separation kernels, formal verification, and rapidly improving techniques relevant to software defect density estimation. Cryptographic separation protects information in transmission and storage. Formally… (More)