5. References

See some of the papers on the Knowbot Programming Environment on CNRI's publications page: ``Knowbot programming: System support for mobile agents'', at http://www.cnri.reston.va.us/home/koe/iwooos.html, and ``Using the Knowbot Operating Environment in a Wide-Area Network'', at http://www.cnri.reston.va.us/home/koe/mos.html. For information on Java's security model, consult the Java Security FAQ at http://java.sun.com/sfaq/index.html.

Perl supports similar features, via a software package called Penguin. Humberto Ortiz Zuazaga wrote a paper called "The Penguin Model for Secure Distributed Internet Scripting", at http://momo.uthscsa.edu/~humberto/project.html. Thanks to Fred Drake for bringing it to my attention.

Work has also been done on Safe-Tcl; see ``The Safe-Tcl Security Model'', by Jacob Y. Levy, Laurent Demailly, John K. Ousterhout, and Brent B. Welch, in the Proceedings of the 1998 USENIX Annual Technical Conference. Usenix members can access the paper online at http://www.usenix.org/publications/library/proceedings/usenix98/levy.html.

The Janus project provides a secure environment for untrusted helper applications by trapping unsafe system calls. The project page is http://www.cs.berkeley.edu/~daw/janus/. Thanks to Paul Prescod for suggesting it.

Can you suggest other links, or some academic references, for this section?