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Polaris: virus-safe computing for Windows XP

It limits the damage a virus can do by using the operating systems own security mechanisms to enforce the Principle of Least Authority on individual applications.

Not one click for security

Conventional wisdom holds that security must negatively affect usability. We have developed SCoopFS (Simple Cooperative File Sharing) as a demonstration that need not be so. SCoopFS ad- dresses the problem of sharing files, both with others and with ourselves across machines. Although SCoopFS provides server authentication, client authorization, and end-to-end encryption, the user never sees any of that. The user interface and underlying infrastructure are designed so that normal user acts of designation provide all the information needed to make the desired security decisions. While SCoopFS is a useful tool, it may be more impor- tant as a demonstration of the usability that comes from designing the infrastructure and user interaction together.

Scalable Access Control ForWeb Services

Controlling access to a large distributed service is a potentially error prone process that may negatively impact request throughput and usability. Our Authorization-Based Access Control (or ABAC) URL rewriter solves this problem by providing locally verifiable authorizations and delegation tracking compatible with common web tools. Our access control mechanism is reusable, distributed and meets the scaling requirements of large distributed services. We demonstrate the successful operation of our proposed mechanism on HPs real-time network monitoring and measurement web service, S3.

Evaluating a Personal Communication Tool: Sidebar

By more closely integrating email with the web we aim to bring organization to email and more collaboration to the web. To this end we developed the Sidebar, a web-browser plug which displays email messages which link to the currently displayed URL. We conducted longitudinal studies on two versions of Sidebar to observe the usage of Sidebar and determine if it improves communications productivity. We found that providing an email summary in Sidebar resulted in raised awareness of the email collaborations, increased serendipitous discovery of information, and resulted in higher reported communication productivity. This paper summarizes Sidebars operation, describes the user studies, and presents conclusions.

Credit transfer for market-based infrastructure

The lingua franca of a market-based resource allocation infrastructure is the credit transfer protocol. The protocol design determines the expressible access-control policies and the supported trading patterns. This paper presents a protocol supporting fine grained manipulation of ownership authorities for enhanced expressiveness.