The authors gratefully acknowledge the support of the National Science Foundation (grant IRI-9711199), the Office of Naval Research (grant N00014-99-1-0417), and the Intel Corporation.
Steven Hofmeyr wrote the original program for analyzing system call traces, Julie Rehmeyr rewrote the code so that it was suitable to run in the kernel, and Geoff Hunsicker developed the original login trojan, which we ported for these experiments. Margo Seltzer suggested some of the benchmarks used in the paper. Erin O'Neill pointed out to us that the immune system is better thought of as a system for maintaining homeostasis than as a defense mechanism. We are grateful to the above people and all the members of the Adaptive Computation group at UNM, especially David Ackley, for their many helpful suggestions and interesting conversations about this work.