Bennet Yee

A sanctuary for mobile agents

The Sanctuary project at UCSD is building a secure infrastructure for mobile agents, and examining the fundamental security limits of such an infrastructure.

Forward-security in private-key cryptography

This paper provides a comprehensive treatment of forwardsecurity in the context of shared-key based cryptographic primitives, as a practical means to mitigate the damage caused by key-exposure. We provide definitions of security, practical proven-secure constructions, and applications for the main primitives in this area. We identify forwardsecure pseudorandom bit generators as the central primitive, providing several constructions and then showing how forward-secure message authentication schemes and symmetric encryption schemes can be built based on standard schemes for these problems coupled with forwardsecure pseudorandom bit generators. We then apply forward-secure message authentication schemes to the problem of maintaining secure access logs in the presence of break-ins.

Cryptographic Postage Indicia

Metered mail provides substantial opportunities for fraud. (Indeed, losses due to meter fraud in the United States are said to exceed

Mobile Agents and Intellectual Property Protection

100 million annually.) We apply cryptographic techniques to prevent several types of improper use of metering indicia.

Mobile agents and intellectual property protection

Technical enforcement of intellectual property (IP) rights often conflicts with the ability to use the IP. This is especially true when the IP is data, which may easily be copied while it is being accessed. As electronic commerce of data becomes more widespread, traditional approaches will prove increasingly problematic. In this paper, we show that the mobile agent architecture is an ideal solution to this dilemma: by providing full access to the data but charging for the transmission of results back to the user — results-based billing — we resolve the access versus protection conflict. We define new requirements for agent frameworks to implement results-based billing: “data-aware accounting” and “data-tight sandboxing”, which, along with the common requirements such as authentication, authorization, agent self-monitoring, and efficiency, provide the mechanisms by which database owners can effectively grant users access to their intellectual property.

Using Secure Coprocessors

Technical enforcemment of intellectual property (IP) rights often conflicts with the ability to use the IP. This is especially true when the IP is data, which may eaisly be copied while it is being accessed. As electronic commerce of data becomes more widespread, traditional approaches will prove increasingly problematic. In this paper, we show that the mobile agent architecture is an ideal solution to this dilemma: by providing full access to the data but charging for the transmission of results back to the user-reslts-based billing-we resulve the access versus protection conflict. We define new requirements for agent frameworks to implement results-based billing: “data-aware accounting” and “data-tight sandboxing”, which, along with the common requirements such as authentication, authorisation, agen self-monitoring, and efficiency, provide the mechanisms by which database owners can effectively grant users access to their intellectual property.