An integrated model of traffic, geography and economy in the Internet (2008)
Holme, Petter, Karlin, Josh, Forrest, Stephanie
Modeling Internet growth is important both for understanding the current network and to predict and improve its future. To date, Internet models have typically attempted to explain a subset of the...
A dual assortative measure of community structure (2008)
Kaplan, Todd D., Forrest, Stephanie
Current community detection algorithms operate by optimizing a statistic called modularity, which analyzes the distribution of positively weighted edges in a network. Modularity does not account for...
Radial Structure of the Internet (2006)
Holme, Petter, Karlin, Josh, Forrest, Stephanie
The structure of the Internet at the Autonomous System (AS) level has been studied by both the Physics and Computer Science communities. We extend this work to include features of the core and the...
Modeling Somatic Evolution in Tumorigenesis (2006)
Sabrina L. Spencer, Ryan A. Gerety, Kenneth J. Pienta, Stephanie Forrest
Tumorigenesis in humans is thought to be a multistep process where certain mutations confer a selective advantage, allowing lineages derived from the mutated cell to outcompete other cells. Although...
Technological networks and the spread of computer viruses (2004)
Balthrop, Justin, Forrest, Stephanie, Newman, M. E. J., Williamson, Matthew M.
Computer infections such as viruses and worms spread over networks of contacts between computers, with different types of networks being exploited by different types of infections. Here we analyze...
Adaptive Radio: Achieving Consensus Using Negative (2004)
Dennis L. Chao, Justin Balthrop, Stephanie Forrest
We introduce the use of negative preferences to produce solutions that are acceptable to a group of users. Using negative preference profiling, a system determines which solutions are unsatisfactory...
Adaptive Radio: Achieving Consensus Using Negative Preferences (2004)
Dennis L. Chao, Justin Balthrop, Stephanie Forrest
We introduce the use of negative preferences to produce solutions that are acceptable to a group of users. Using negative preference profiling, a system determines which solutions are unsatisfactory...
Randomized Instruction Set Emulation (2003)
Gabriela Barrantes, David H. Ackley, Trek S. Palmer, Dino Dai Zovi, Stephanie Forrest, Darko Stefanovic
Many remote attacks against computer systems inject binary code into the execution path of a running program, gaining control of the program's behavior. If each defended system or program could use a...
Randomized Instruction Set Emulation to Disrupt Binary Code Injection Attacks (2003)
Elena Gabriela Barrantes, David H. Ackley, Stephanie Forrest, Trek S. Palmer, Darko Stefanovi C, Dino Dai Zovi
Binary code injection into an executing program is a common form of attack. Most current defenses against this form of attack use a `guard all doors' strategy, trying to block the avenues by which...
Object Lifetime Prediction in Java (2003)
Hajime Inoue, Darko Stefanovic, Stephanie Forrest
Accurately predicting the lifetimes of objects in object-oriented and functional languages is important because such predictions can be used to improve memory management performance at run-time. A...
Coverage and Generalization in an Artificial Immune System (2003)
Justin Balthrop, Fernando Esponda, Stephanie Forrest, Matthew Glickman
LISYS is an artificial immune system framework which is specialized for the problem of network intrusion detection. LISYS learns to detect abnormal packets by observing normal network tra#c. Because...
Stochastic Stage-structured Modeling of the Adaptive Immune System (2003)
Dennis L. Chao, Miles P. Davenport, Stephanie Forrest, Alan S. Perelson
We have constructed a computer model of the cytotoxic T lymphocyte (CTL) response to antigen and the maintenance of immunological memory. Because immune responses often begin with small numbers of...
Information Immune Systems (2003)
Dennis L. Chao, Stephanie Forrest
The concept of an information immune system (IIS) is introduced, in which undesirable information is eliminated before it can reach the user. The IIS is inspired by the natural immune systems that...
Stochastic Stage-structured Modeling of the Adaptive Immune System (2003)
Dennis L. Chao, Miles P. Davenport, Stephanie Forrest, Alan S. Perelson
We have constructed a computer model of the cytotoxic T lymphocyte (CTL) response to antigen and the maintenance of immunological memory. Because immune responses often begin with small numbers of...
Generating Biomorphs with an Aesthetic Immune System (2003)
Dennis L. Chao, Stephanie Forrest
We describe an interactive search algorithm inspired by the immune system. The algorithm learns what parts of the search space are not useful to help a user explore large parameter spaces e#ciently....
Effective Feedback in the Immune System (2003)
Christina Warrender, Stephanie Forrest, Lee Segel
this paper, we explore methods for automatically discovering and optimally quantitating such adaptive response mechanisms. The general approach is to make the system exible enough to respond to many...
Generating Biomorphs with an Aesthetic Immune System (2003)
Dennis L. Chao, Stephanie Forrest
We describe an interactive search algorithm inspired by the immune system. The algorithm learns what parts of the search space are not useful to help a user explore large parameter spaces eciently....
Information Immune Systems (2003)
Dennis L. Chao, Stephanie Forrest
Many people are exposed to more information than they can process eectively. We describe an approach to building an information immune system that eliminates undesirable information before it reaches...
Coverage and Generalization in an Arti (2002)
Justin Balthrop, Fernando Esponda, Stephanie Forrest, Matthew Glickman
LISYS is an arti cial immune system framework which is specialized for the problem of network intrusion detection. LISYS learns to detect abnormal packets by observing normal network trac. Because...
Revisiting LISYS: Parameters and Normal Behavior (2002)
Justin Balthrop, Stephanie Forrest, Matthew R. Glickman
This paper studies a simplified form of LISYS, an artificial immune system for network intrusion detection. The paper describes results based on a new, more controlled data set than that used for...
Computation in the Wild (2002)
Stephanie Forrest, Justin Balthrop, Matthew Glickman, David Ackley
this paper we outline the biological principles we believe to be most relevant to understanding and designing the computational networks of the future. Among the principles of living systems we see...
Generating Biomorphs with an Aesthetic Immune System (2002)
Dennis L. Chao, Stephanie Forrest
We describe an interactive search algorithm inspired by the immune system. The algorithm learns what parts of the search space are not useful to help a user explore large parameter spaces...
Information Immune Systems (2002)
Dennis L. Chao, Stephanie Forrest
Many people are exposed to more information than they can process effectively. We describe an approach to building an information immune system that eliminates undesirable information before it...
Information Immune Systems (2002)
Dennis L. Chao, Stephanie Forrest
Many people are exposed to more information than they can process eectively. We describe an approach to building an information immune system that eliminates undesirable information before it reaches...
Revisiting LISYS: Parameters and Normal Behavior (2002)
Justin Balthrop, Stephanie Forrest, Matthew R. Glickman
This paper studies a simpli ed form of LISYS, an arti cial immune system for network intrusion detection. The paper describes results based on a new, more controlled data set than that used for...
Anil Somayaji, Stephanie Forrest
Automated intrusion response is an important unsolved problem in computer security. A system called pH (for process homeostasis) is described which can successfully detect and stop intrusions before...
Genetic Algorithms for Finding Polynomial (2001)
Jurgen Giesl, Fernando Esponda, Stephanie Forrest
Polynomial orderings are a well-known method to prove termination of term rewriting systems. However, for an automation of this method, the crucial point is to find suitable coe#cients by machine. We...
Eective Feedback in the Immune System (2001)
Christina Warrender, Stephanie Forrest, Lee Segel
this paper, we explore methods for automatically discovering and optimally quantitating such adaptive response mechanisms. The general approach is to make the system exible enough to respond to many...
Immunity by Design: An Artificial Immune System (2001)
Steven A. Hofmeyr, Stephanie Forrest
We describe an artificial immune system (AIS) that is distributed, robust, dynamic, diverse and adaptive. It captures many features of the vertebrate immune system and places them in the context of...
Immunology as Information Processing (2000)
Stephanie Forrest, Steven A. Hofmeyr
This chapter describes the behavior of the immune system from an informationprocessing perspective. It reviews a series of projects conducted at the University of New Mexico and the Santa Fe...
Automated Response Using System-Call Delays (2000)
Anil Somayaji, Stephanie Forrest
Automated intrusion response is an important unsolved problem in computer security. A system called pH (for process homeostasis) is described which can successfully detect and stop intrusions before...
Principles of a Computer Immune System (2000)
Anil Somayaji, Steven Hofmeyr, Stephanie Forrest
Natural immune systems provide a rich source of inspiration for computer security in the age of the Internet. Immune systems have many features that are desirable for the imperfect, uncontrolled, and...
A Sense of Self for Unix Processes (2000)
Stephanie Forrest, Steven A. Hofmeyr, Anil Somayaji, Thomas A. Longstaff
A method for anomaly detection is introduced in which "normal" is defined by short-range correlations in a process ' system calls. Initial experiments suggest that the definition is stable during...
Immunity by Design: An Artificial Immune System (1999)
Steven A. Hofmeyr, Stephanie Forrest
We describe an artificial immune system (AIS) that is distributed, robust, dynamic, diverse and adaptive. It captures many features of the vertebrate immune system and places them in the context of...
Immunity by Design: An Artificial Immune System (1999)
Steven A. Hofmeyr, Stephanie Forrest
We describe an artificial immune system (AIS) that is distributed, robust, dynamic, diverse and adaptive. It captures many features of the vertebrate immune system and places them in the context of...
John Holland's Invisible Hand: An Artificial Immune System (1999)
Stephanie Forrest, Steven A. Hofmeyr
We describe an artificial immune system (AIS) that is distributed, robust, dynamic, diverse and adaptive. It captures many features of the vertebrate immune system and places them in the context of...
Intrusion Detection using Sequences of System Calls (1999)
Steven A. Hofmeyr, Stephanie Forrest, Anil Somayaji
A method is introducted for detecting intrusions at the level of privileged processes. Evidence is given that short sequences of system calls executed by running processes are a good discriminator...
Steven A. Hofmeyr, Stephanie Forrest, Anil Somayaji
this paper we are primarily concerned with determining empirically if the discriminator is stable. Efficiency is a secondary consideration, and is addressed in this paper to the extent that we...
Detecting Intrusions Using System Calls: Alternative Data Models (1999)
Christina Warrender, Stephanie Forrest, Barak Pearlmutter
Intrusion detection systems rely on a wide variety of observable data to distinguish between legitimate and illegitimate activities. In this paper we study one such observable--- sequences of system...
Detecting Intrusions Using System Calls: Alternative Data Models (1999)
Christina Warrender, Stephanie Forrest, Barak Pearlmutter
Intrusion detection systems rely on a wide variety of observable data to distinguish between legitimate and illegitimate activities. In this paper we study one such observable--- sequences of system...
John Holland's Invisible Hand: An Artificial Immune System (1999)
Stephanie Forrest, Steven A. Hofmeyr
We describe an artificial immune system (AIS) that is distributed, robust, dynamic, diverse and adaptive. It captures many features of the vertebrate immune system and places them in the context of...
Principles of a Computer Immune System (1999)
Anil Somayaji, Steven Hofmeyr, Stephanie Forrest
Natural immune systems provide a rich source of inspiration for computer security in the age of the Internet. Immune systems have many features that are desirable for the imperfect, uncontrolled, and...
Mihaela Oprea, Stephanie Forrest
The immune system uses many strategies to generate its enormous repertoire of diverse antibodies, but their relative importance is not understood. Here we address the contribution of antibody gene...
John Holland's Invisible Hand: An Artificial Immune System (1999)
Stephanie Forrest, Steven A. Hofmeyr
We describe an artificial immune system (AIS) that is distributed, robust, dynamic, diverse and adaptive. It captures many features of the vertebrate immune system and places them in the context of...
Detecting Intrusions Using System Calls: Alternative Data Models (1999)
Christina Warrender, Stephanie Forrest, Barak Pearlmutter
Intrusion detection systems rely on a wide variety of observable data to distinguish between legitimate and illegitimate activities. In this paper we study one such observable--- sequences of system...
Mihaela Oprea, Stephanie Forrest
The immune system uses many strategies to generate its enormous repertoire of diverse antibodies, but their relative importance is not understood. As part of a larger project to quantify their...
A Sense of Self for Unix Processes (1999)
Stephanie Forrest, Steven A. Hofmeyr, Anil Somayaji, Thomas A. Longstaff
A method for anomaly detection is introduced in which "normal" is defined by short-range correlations in a process ' system calls. Initial experiments suggest that the definition is stable during...
Peter T. Hraber, Terry Jones, Stephanie Forrest
This paper describes one such model, called Echo, whose emphasis is on the essential components and interactions of ecosystems. Many CAS can be viewed as ecologies (e.g., [24, 46]), but our focus in...
Peter T. Hraber, Terry Jones, Stephanie Forrest
This paper describes one such model, called Echo, whose emphasis is on the essential components and interactions of ecosystems. Many CAS can be viewed as ecologies (e.g., [24, 46]), but our focus in...
The Evolution of Emergent Organization in Immune System Gene Libraries (1999)
Ron R. Hightower, Stephanie Forrest, Alan S. Perelson
A binary model of the immune system is used to study the effects of evolution on the genetic encoding for antibody molecules. One feature of this encoding is that, unlike typical genetic algorithm...
The Baldwin Effect in the Immune System: Learning by Somatic Hypermutation (1999)
Ron Hightower, Stephanie Forrest, Alan S. Perelson
This paper discusses the Baldwin effect with respect to the immune system---a learning mechanism that rivals the complexity and computational power of the nervous system. In previous work we used a...
Genetic Algorithms, Operators, and DNA Fragment Assembly (1999)
Rebecca J. Parsons, Stephanie Forrest, Christian Burks
. We study different genetic algorithm operators for one permutationproblem associated with the Human Genome Project---the assembly of DNA sequence fragments from a parent clone whose sequence is...
Steven A. Hofmeyr, Stephanie Forrest
This paper introduces a method of distributed network intrusion detection which scales with the number of computers on a network and is tunable (the probability of detection can be traded off against...
Detecting Intrusions Using System Calls: Alternative Data Models (1998)
Christina Warrender, Stephanie Forrest, Barak Pearlmutter
Intrusion detection systems rely on a wide variety of observable data to distinguish between legitimate and illegitimate activities. In this paper we study one such observable---sequences of system...
Principles of a Computer Immune System (1998)
Anil Somayaji, Steven Hofmeyr, Stephanie Forrest
Natural immune systems provide a rich source of inspiration for computer security in the age of the Internet. Immune systems have many features that are desirable for the imperfect, uncontrolled, and...
Stephanie Forrest, Steven A. Hofmeyr, Anil Somayaji
Natural immune systems protect animals from dangerous foreign pathogens, including bacteria, viruses, parasites, and toxins. Their role in the body is analogous to that of computer security systems...
Intrusion Detection using Sequences of System Calls (1998)
Steven A. Hofmeyr, Stephanie Forrest, Anil Somayaji
this paper we are primarily concerned with determining empirically if the discriminator is stable. Efficiency is a secondary consideration, and is addressed in this paper to the extent that we...
Building Diverse Computer Systems (1998)
Stephanie Forrest, Anil Somayaji, David H. Ackley
Diversity is an important source of robustness in biological systems. Computers, by contrast, are notable for their lack of diversity. Although homogeneous systems have many advantages, the...
A Sense of Self for Unix Processes (1998)
Stephanie Forrest, Steven A. Hofmeyr, Anil Somayaji, Thomas A. Longstaff
A method for anomaly detection is introduced in which "normal" is defined by short-range correlations in a process ' system calls. Initial experiments suggest that the definition is stable during...
Self-Nonself Discrimination in a Computer (1998)
Stephanie Forrest, Alan S. Perelson, Lawrence Allen, Rajesh Cherukuri
The problem of protecting computer systems can be viewed generally as the problem of learning to distinguish self from other. We describe a method for change detection which is based on the...
Self-Nonself Discrimination in a Computer (1998)
Stephanie Forrest, Alan S. Perelson, Lawrence Allen, Rajesh Cherukuri
The problem of protecting computer systems can be viewed generally as the problem of learning to distinguish self from other. We describe a method for change detection which is based on the...
Computational Immunology for the Defense of Large Scale Systems (1998)
Marceau, Carla, Stillerman, Matthew, Stiliman, Maureen, Forrest, Stephanie
This report describes the application of the computational immunology approach to a distributed object systems. The hypothesis tested was that one could characterize normal behavior of the...
Automated Diversity in Computer Systems (1998)
Attackers penetrate a large number of computers by exploiting common vulnerabilities. The objective of this effort is to address this internet-wide weakness by introducing diversity into computers so...
Genetic Algorithms and Artificial Life (1998)
Melanie Mitchell, Stephanie Forrest
Genetic algorithms are computational models of evolution that play a central role in many artificial-life models. We review the history and current scope of research on genetic algorithms in...
Terry Jones, Stephanie Forrest
Echo is a generic ecosystem model in which evolving agents are situated in a resource-limited environment. The Echo model is described, and the behavior of Echo is evaluated on two well-studied...
Intrusion Detection using Sequences of System Calls (1998)
Steven A. Hofmeyr, Stephanie Forrest, Anil Somayaji
this paper we are primarily concerned with determining empirically if the discriminator is stable. Efficiency is a secondary consideration, and is addressed in this paper to the extent that we...
Genetic Algorithms and Artificial Life (1998)
Melanie Mitchell, Stephanie Forrest
Genetic algorithms are computational models of evolution that play a central role in many artificial-life models. We review the history and current scope of research on genetic algorithms in...
When Will a Genetic Algorithm Outperform Hill Climbing? (1998)
Melanie Mitchell, John H. Holland, Stephanie Forrest
We analyze a simple hill-climbing algorithm (RMHC) that was previously shown to outperform a genetic algorithm (GA) on a simple "Royal Road" function. We then analyze an "idealized" genetic algorithm...
Stephanie Forrest, Melanie Mitchell
What makes a problem easy or hard for a genetic algorithm (GA)? This question has become increasingly important as people have tried to apply the GA to ever more diverse types of problems. Much...
A Sense of Self for Unix Processes (1998)
Stephanie Forrest, Steven A. Hofmeyr, Anil Somayaji, Thomas A. Longstaff
A method for anomaly detection is introduced in which "normal" is defined by short-range correlations in a process ' system calls. Initial experiments suggest that the definition is stable during...
Stephanie Forrest, Steven A. Hofmeyr, Anil Somayaji
this article argues that the similarities are compelling and could point the way to improved computer security. Improvements can be achieved by designing computer immune systems that have some of the...
Principles of a Computer Immune System (1998)
Anil Somayaji, Steven Hofmeyr, Stephanie Forrest
Vertebrate immune systems provide a rich source of inspiration for computer security in the age of the Internet. Immune systems have many features that are desirable for the imperfect, uncontrolled,...
Using Lazy Evaluation to Simulate Realistic-Size Repertoires in Models of the Immune System (1997)
Derek J. Smith, Stephanie Forrest, David H. Ackley, Alan S. Perelson
We describe a method of implementing efficient computer simulations of immune systems that have a large number of unique B and/or T cell clones. The method uses an implementation technique called...
Modeling the Effects of Prior Infection on Vaccine Efficacy (1997)
Derek J. Smith, Stephanie Forrest, David H. Ackley, Alan S. Perelson
We performed computer simulations to study the effects of prior infection on vaccine efficacy. We injected three antigens sequentially. The first antigen, designated the prior, represented a prior...
Deriving Shape Space Parameters from Immunological Data (1997)
Derek J. Smith, Stephanie Forrest, Ron R. Hightower, Alan S. Perelson
We present a method for deriving shape space parameters that are consistent with immunological data, and illustrate the method by deriving shape space parameters for a model of cross-reactive memory....
Immunological Memory is Associative (1997)
Derek J. Smith, Stephanie Forrest, Alan S. Perelson
This paper argues that immunological memory is in the same class of associative memories as Kanerva's Sparse Distributed Memory, Albus's Cerebellar Model Arithmetic Computer, and Marr's Theory of the...
Deriving Shape Space Parameters from Immunological Data (1997)
Derek J. Smith, Stephanie Forrest, Ron R. Hightower, Alan S. Perelson
We present a method for deriving shape space parameters that are consistent with immunological data, and illustrate the method by deriving shape space parameters for a model of cross-reactive memory....
Peter T. Hraber, Terry Jones, Stephanie Forrest
This paper describes one such model, called Echo, whose emphasis is on the essential components and interactions of ecosystems. Many CAS can be viewed as ecologies (e.g., [24, 46]), but our focus in...
Stephanie Forrest, Steven A. Hofmeyr, Anil Somayaji
this article argues that the similarities are compelling and could point the way to improved computer security. Improvements can be achieved by designing computer immune systems that have some of the...
Building Diverse Computer Systems (1997)
Stephanie Forrest, Anil Somayaji, David H. Ackley
Diversity is an important source of robustness in biological systems. Computers, by contrast, are notable for their lack of diversity. Although homogeneous systems have many advantages, the...
Fitness Distance Correlation as a Measure of Problem Difficulty for Genetic Algorithms (1997)
Terry Jones, Stephanie Forrest
A measure of search difficulty, fitness distance correlation (FDC), is introduced and examined in relation to genetic algorithm (GA) performance. In many cases, this correlation can be used to...