National Institute of Standards and Technology における超伝導研究及び生活

In the last years, wireless sensor networks (WSNs) have gained increasing attention from both the research community and actual users. As sensor nodes are generally battery-powered devices, the critical aspects to face concern how to reduce the energy consumption of nodes, so that the network lifetime can be extended to reasonable times. In this paper we first break down the energy consumption for the components of a typical sensor node, and discuss the main directions to energy conservation in WSNs. Then, we present a systematic and comprehensive taxonomy of the energy conservation schemes, which are subsequently discussed in depth. Special attention has been devoted to promising solutions which have not yet obtained a wide attention in the literature, such as techniques for energy efficient data acquisition. Finally we conclude the paper with insights for research directions about energy conservation in WSNs.

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Energy conservation in wireless sensor networks: A survey

This paper presents control and coordination algorithms for groups of vehicles. The focus is on autonomous vehicle networks performing distributed sensing tasks where each vehicle plays the role of a mobile tunable sensor. The paper proposes gradient descent algorithms for a class of utility functions which encode optimal coverage and sensing policies. The resulting closed-loop behavior is adaptive, distributed, asynchronous, and verifiably correct.

Coverage control for mobile sensing networks

The objective of this paper is to give a comprehensive introduction to applied cryptography with an engineer or computer scientist in mind. The emphasis is on the knowledge needed to create practical systems which supports integrity, confidentiality, or authenticity. Topics covered includes an introduction to the concepts in cryptography, attacks against cryptographic systems, key use and handling, random bit generation, encryption modes, and message authentication codes. Recommendations on algorithms and further reading is given in the end of the paper. This paper should make the reader able to build, understand and evaluate system descriptions and designs based on the cryptographic components described in the paper.

[서평]「Applied Cryptography」

This book attempts to achieve a difficult goal: to teach statistics to the novice so as to impart a liking and understanding of statistics. The book is geared toward a medical audience, since most examples are from the medical literature. The structure of the book consists of the following elements in each chapter: a small number of statistical rules of thumb, followed by a nontechnical explanation, a demonstration of how to work through the mechanics of doing the statistical test in question, a summary, and sample problems to be solved by the reader. (The answers, with explanations, are provided in an appendix.) Although a variety of univariate statistics are included, certain topics that are important in medical research are not. For example, there is little or no discussion of multiple regression, life-table techniques, or pooling of studies. These omissions, especially of multiple regression, are unfortunate. The Primer was derived from

Primer of Biostatistics

Currently, in the smartphone market, Android is the platform with the highest share. Due to this popularity and also to its open source nature, Android-based smartphones are now an ideal target for attackers. Since the number of malware designed for Android devices is increasing fast, Android users are looking for security solutions aimed at preventing malicious actions from damaging their smartphones.

In this paper, we describe MADAM, a Multi-level Anomaly Detector for Android Malware. MADAM concurrently monitors Android at the kernel-level and user-level to detect real malware infections using machine learning techniques to distinguish between standard behaviors and malicious ones. The first prototype of MADAM is able to detect several real malware found in the wild. The device usability is not affected by MADAM due to the low number of false positives generated after the learning phase.

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MADAM: a multi-level anomaly detector for android malware

Android users are constantly threatened by an increasing number of malicious applications (apps), generically called malware. Malware constitutes a serious threat to user privacy, money, device and file integrity. In this paper we note that, by studying their actions, we can classify malware into a small number of behavioral classes, each of which performs a limited set of misbehaviors that characterize them. These misbehaviors can be defined by monitoring features belonging to different Android levels. In this paper we present MADAM, a novel host-based malware detection system for Android devices which simultaneously analyzes and correlates features at four levels: kernel, application, user and package, to detect and stop malicious behaviors. MADAM has been specifically designed to take into account those behaviors that are characteristics of almost every real malware which can be found in the wild. MADAM detects and effectively blocks more than 96 percent of malicious apps, which come from three large datasets with about 2,800 apps, by exploiting the cooperation of two parallel classifiers and a behavioral signature-based detector. Extensive experiments, which also includes the analysis of a testbed of 9,804 genuine apps, have been conducted to show the low false alarm rate, the negligible performance overhead and limited battery consumption.

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MADAM: Effective and Efficient Behavior-based Android Malware Detection and Prevention

ZigBee outlines a new suite of protocols targeted at low-rate, low-power devices and sensor nodes. ZigBee Specification includes a number of security provisions and options. The security model specified in the Smart Energy Profile seems bound to become the reference security model for most of ZigBee applications. In this paper we review this security model and highlight places where its specification presents concerns and possible inefficiencies in security management. Specifically, we show that the specification does not adequately address the forward security requirement so allowing a number of threats at the routing and application layer. Furthermore, we show inefficiencies in managing both the Network Key and devices certificates. Finally, we make some proposals to address these problems.

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Considerations on Security in ZigBee Networks

In a Wireless Sensor Network, sensor nodes may fail for several reasons and the network may split into two or more disconnected partitions. This may deteriorate or even nullify the usefulness and effectiveness of the network. Therefore, repairing partitions is a priority. In this paper we present a method to repair network partitions by using mobile nodes. By reasoning upon the degree of connectivity with neighbours, a mobile node finds the proper position where to stop in order to re-establish connectivity. Factors influencing the method performance are singled out and criteria for their selection are discussed. Simulations show that the proposed method is effective and efficient notwithstanding packet loss.

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An algorithm for reconnecting wireless sensor network partitions

A Delay Tolerant Network (DTN) relies on the implicit assumption that nodes cooperate towards message forwarding. However, this assumption cannot be satisfied when there are malicious nodes acting as blackholes and voluntarily attracting and dropping messages.In this paper we propose a reputation-based protocol for contrasting blackholes. Every node locally maintains the reputation of forwarding nodes it comes in touch with and, then, upon selecting the next forwarding node, the node chooses among those having the highest reputation. The proposed reputation protocol is composed of three basic mechanisms-acknowledgments, node lists, and aging-that make communication efficient and capable of adapting to the changing operating conditions of a DTN.The protocol has been used to extend CAR 1]. The resulting protocol RCAR (reputation-based CAR) has been compared with T-ProPHET 2], a state-of-the-art reputation-based DTN routing protocol, from several standpoints. As it turns out, RCAR is more effective than T-ProPHET and outperforms it in most cases.

/pdf/towards-a-reputation-based-routing-protocol-to-contrast-14ks7qgfub.pdf

Gianluca Dini

Papers

MADAM: a multi-level anomaly detector for android malware

MADAM: Effective and Efficient Behavior-based Android Malware Detection and Prevention

Considerations on Security in ZigBee Networks

An algorithm for reconnecting wireless sensor network partitions

Towards a reputation-based routing protocol to contrast blackholes in a delay tolerant network