This ebook is the first authorized digital version of Kernighan and Ritchie's 1988 classic, The C Programming Language (2nd Ed.). One of the best-selling programming books published in the last fifty years, "K&R" has been called everything from the "bible" to "a landmark in computer science" and it has influenced generations of programmers. Available now for all leading ebook platforms, this concise and beautifully written text is a "must-have" reference for every serious programmers digital library.

As modestly described by the authors in the Preface to the First Edition, this "is not an introductory programming manual; it assumes some familiarity with basic programming concepts like variables, assignment statements, loops, and functions. Nonetheless, a novice programmer should be able to read along and pick up the language, although access to a more knowledgeable colleague will help."

The C programming language

The advent of the smart grid promises to usher in an era that will bring intelligence, efficiency, and optimality to the power grid. Most of these changes will occur as an Internet-like communications network is superimposed on top of the current power grid using wireless mesh network technologies with the 802.15.4, 802.11, and WiMAX standards. Each of these will expose the power grid to cybersecurity threats. In order to address this issue, this work proposes a distributed intrusion detection system for smart grids (SGDIDS) by developing and deploying an intelligent module, the analyzing module (AM), in multiple layers of the smart grid. Multiple AMs will be embedded at each level of the smart grid-the home area networks (HANs), neighborhood area networks (NANs), and wide area networks (WANs)-where they will use the support vector machine (SVM) and artificial immune system (AIS) to detect and classify malicious data and possible cyberattacks. AMs at each level are trained using data that is relevant to their level and will also be able to communicate in order to improve detection. Simulation results demonstrate that this is a promising methodology for supporting the optimal communication routing and improving system security through the identification of malicious network traffic.

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Distributed Intrusion Detection System in a Multi-Layer Network Architecture of Smart Grids

The anomaly-detection problem can be formulated as one of learning to characterize the behaviors of an individual, system, or network in terms of temporal sequences of discrete data. We present an approach on the basis of instance-based learning (IBL) techniques. To cast the anomaly-detection task in an IBL framework, we employ an approach that transforms temporal sequences of discrete, unordered observations into a metric space via a similarity measure that encodes intra-attribute dependencies. Classification boundaries are selected from an a posteriori characterization of valid user behaviors, coupled with a domain heuristic. An empirical evaluation of the approach on user command data demonstrates that we can accurately differentiate the profiled user from alternative users when the available features encode sufficient information. Furthermore, we demonstrate that the system detects anomalous conditions quickly — an important quality for reducing potential damage by a malicious user. We present several techniques for reducing data storage requirements of the user profile, including instance-selection methods and clustering. As empirical evaluation shows that a new greedy clustering algorithm reduces the size of the user model by 70%, with only a small loss in accuracy.

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Temporal sequence learning and data reduction for anomaly detection

AAFID is a distributed intrusion detection architecture and system, developed in CERIAS at Purdue University. AAFID was the first architecture that proposed the use of autonomous agents for doing intrusion detection. With its prototype implementation, it constitutes a useful framework for the research and testing of intrusion detection algorithms and mechanisms. We describe the AAFID architecture and the existing prototype, as well as some design and implementation experiences and future research issues. ” 2000 Elsevier Science B.V. All rights reserved.

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Intrusion detection using autonomous agents

The anomaly-detection problem can be formulated as one of learning to characterize the behaviors of an individual, system, or network in terms of temporal sequences of discrete data. We present an approach on the basis of instance-based learning (IBL) techniques. To cast the anomaly-detection task in an IBL framework, we employ an approach that transforms temporal sequences of discrete, unordered observations into a metric space via a similarity measure that encodes intra-attribute dependencies. Classification boundaries are selected from an a posteriori characterization of valid user behaviors, coupled with a domain heuristic. An empirical evaluation of the approach on user command data demonstrates that we can accurately differentiate the profiled user from alternative users when the available features encode sufficient information. Furthermore, we demonstrate that the system detects anomalous conditions quickly — an important quality for reducing potential damage by a malicious user. We present several techniques for reducing data storage requirements of the user profile, including instance-selection methods and clustering. An empirical evaluation shows that a new greedy clustering algorithm reduces the size of the user model by 70%, with only a small loss in accuracy.

/pdf/temporal-sequence-learning-and-data-reduction-for-anomaly-rfaan8wdal.pdf

The intrusion detection system architectures commonly used in commercial and research systems have a number of problems that limit their configurability, scalability or efficiency. The most common shortcoming in the existing architectures is that they are built around a single monolithic entity that does most of the data collection and processing. In this paper, we review our architecture for a distributed intrusion detection system based on multiple independent entities working collectively. We call these entities autonomous agents. This approach solves some of the problems previously mentioned. We present the motivation and description of the approach, partial results obtained from an early prototype, a discussion of design and implementation issues, and directions for future work.

An architecture for intrusion detection using autonomous agents

A method, system and apparatus for preventing Denial of Service (DOS) attacks on a device are provided. The method includes determining that the device is receiving DOS attack vectors. The method further includes identifying the attack vector with the highest idle time and removing the identified attack vector. Further, the method includes repeating identifying and removing the identified attack vector until the number of attack vectors falls below a threshold value.

Method and system for preventing DOS attacks

A method for securing a communication network is provided. A communication session established between a local media endpoint located in a communication network and a remote media endpoint is detected. The communication session is assigned a session identifier. Packets communicated to the communication network are monitored. During a predetermined time period, only packets that identify the session identifier, a network address of the local media endpoint, a port of the local media endpoint, a network address of the remote media endpoint, and any port of the remote media endpoint are passed. After the predetermined time period, only packets that identify the session identifier, the network address of the local media endpoint, the port of the local media endpoint, the network address of the remote media endpoint, and a specific one of the ports of the remote media endpoint identified in packets passed during the predetermined time period are passed.

Jai S. Balasubramaniyan

Papers

An architecture for intrusion detection using autonomous agents

Method and system for preventing DOS attacks

System and method for securing a communication network