Showing papers by "Richard R. Brooks published in 2007"

On the Detection of Clones in Sensor Networks Using Random Key Predistribution

Abstract: Random key predistribution security schemes are well suited for use in sensor networks due to their low overhead However, the security of a network using predistributed keys can be compromised by cloning attacks In this attack, an adversary breaks into a sensor node, reprograms it, and inserts several copies of the node back into the sensor network Cloning gives the adversary an easy way to build an army of malicious nodes that can cripple the sensor network In this paper, we propose an algorithm that a sensor network can use to detect the presence of clones Keys that are present on the cloned nodes are detected by looking at how often they are used to authenticate nodes in the network Simulations verify that the proposed method accurately detects the presence of clones in the system and supports their removal We quantify the extent of false positives and false negatives in the clone detection process

Mobile Network Analysis Using Probabilistic Connectivity Matrices

Abstract: Researchers use random graph models to analyze complex networks that have no centralized control such as the Internet, peer-to-peer systems, and mobile ad hoc networks. These models explain phenomena like phase changes, clustering, and scaling. It is necessary to understand these phenomena when designing systems where exact node configurations cannot be known in advance. This paper presents a method for analyzing random graph models that combine discrete mathematics and probability theory. A graph connectivity matrix is constructed where each matrix element is the Bernoulli probability that an edge exists between two given nodes. We show how to construct these matrices for many graph classes, and use linear algebra to analyze the connectivity matrix. We present an application that uses this approach to analyze network cluster self-organization for sensor network security. We conclude by discussing the use of these concepts in mobile systems design.

On Computing Reliability and Expected Hop Count of Wireless Communication Networks

Abstract: The (s,t) expected-hop-count (EHC) in a wireless communication network (WCN), modeled as a graph with probabilistic node failures, is the expected number of operational nodes that a message must traverse from a node s to reach its destination node t. A typical solution for the problem uses factoring theorem to compute the EHC of WCN. Instead, this paper proposes a 2-step approach that utilizes the sum-of-disjoint-product (SDP) technique. First, we provide an efficient technique to generate all (s,t) simple paths considering only the nodes of the WCN. We also propose an efficient algorithm to enumerate all (s,t) simple paths of an interval-graph. Second, we propose using the SDP technique over the paths to compute the reliability and EHC. We show (conjecture) that our SDP-based technique solves the reliability measures in polynomial time (pseudo-polynomial) for WCN containing all disjoint-paths (forming an interval-graph). Simulations on several WCN under various conditions show that the SDP-based technique computes the reliability and EHC in several orders of magnitude faster than the existing factoring-based algorithm. The paper also discusses some application of the reliability measures.

Performance aware secure code partitioning

Abstract: Many embedded applications exist where decisions are made using sensitive information. A critical issue in such applications is to ensure that data is accessed only by authorized computing entities. In many scenarios, these entities do not rely on each other, yet they need to work on a secure application in parallel to complete application execution under the specified deadline. Our focus in this paper is on compiler-guided secure code partitioning among a set of hosts. The scenario targeted involves a set of hosts that want to execute a secure embedded application in parallel. The various hosts have different levels of access to the data structures manipulated in the application. Our approach partitions the application among the hosts such that the load imbalance across hosts is minimized to reduce execution time while ensuring that no security leak occurs.

Wireless Sensor Networks: Edited by C. S. Raghavendra, K. M. Sivalingam, and T. Znati

Abstract: This book consists of 18 chapters dealing with the most important wireless sensor net issues from the most authoritative authors. It would be reasonable to include this book in any sensor net refer...

On-Line Behavior Recognition for Situation and Threat Assessment

Abstract: [] The e-Machine is a hidden Markov model generalization that does not require a priori knowledge of the state structure of a system or the transition probabilities between the states. In this work, we discuss how e-Machines are used to locate and analyze behavioral patterns in symbolized input data streams. We explain how the e-Machine can be used to recognize when certain patterns occur.

Optimal Layout of Multicast Groups Using Network Embedded Multicast Security in Ad Hoc Sensor Networks

Abstract: This paper considers the security of sensor network applications. Our approach creates multicast regions that use symmetric key cryptography for communications. Each multicast region contains a single keyserver that is used to perform key management and maintain the integrity of a multicast region. Communications between two multicast regions is performed by nodes that belong to both regions. To ease the network management burden, it is desirable for the networks to self-organize into regions and dynamically select their keyservers. This paper shows how to determine the number of keyservers (k) to use and the size in the number of hops (h) of their multicast regions. We find that power consumption issues provide a natural trade-off that determines optimal values for these parameters. Analysis of one application shows an increase in system security with 70-80% less power overhead than existing security approaches.