The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Distributed systems usually provide services with varying criticalities. Failures of core services lead to catastrophic consequences to the system. Maintaining system core services' availability with limited resources has become a challenging issue, especially when system operates in an adversary environment and face malicious under attack. This paper discusses the attacker-defender problem and analyzes...
We examine three binary voting algorithms used with computer replication for fault tolerance and separately observe the resultant reliability and security. We offer insights to answer the question: Can a voting algorithm provide a system with both security and reliability? We show that while random dictator (i.e., randomly choosing one of the replicas) provides good security and majority rule yields...
In this paper, we propose a routing protocol in an ad hoc network that ensures timely delivery of real-time data packets. This is achieved by carefully accessing the resources available to a route before a session is admitted along that route. Each link in the route is checked for sufficient bandwidth not only for the new session to be admitted but also for the sessions that are already using that...
As new techniques of fault tolerance and security emerge, so does the need for suitable tools to evaluate them. Generally, the security of a system can be estimated and verified via logical test cases, but the performance overhead of security algorithms on a system needs to be numerically analyzed. The diversity in security methods and design of fault tolerant systems make it impossible for researchers...
Identification and isolation of attackers in a distributed system is a challenging problem. This problem is even more aggravated in a wireless network because the unreliable channel makes the actions of the users (nodes) hidden from each other. Therefore, legitimate users can only construct a belief about a potential attacker through monitoring and observation. In this paper, we use game theory to...
An underlying assumption of multi-hop data communication in ad hoc networks is that the nodes forward each others' packets. An important challenge in such scenario is to attain mutual cooperation. This paper provides a game theoretic solution to enforce cooperation in ad hoc network in the presence of channel noise. We focus on the packet forwarding process and model it as a hidden action game with...
In this paper, we use game theory to study the interactions between a malicious node and a regular node in wireless networks with unreliable channels. Since the malicious nodes do not reveal their identities to others, it is crucial for the regular nodes to detect them through monitoring and observation. We model the malicious node detection process as a Bayesian game with imperfect information and...
Numerous routing protocols have been proposed for wireless sensor networks, each of which is highly optimized for a certain class of traffic, like real time, reliable sense and disseminate, network reprogramming, energy efficiency and so on. However, a typical deployment demands an arbitrary communication pattern that generates multiple traffic types simultaneously. Arguably, no single routing protocol...
In this paper, we investigate how cognitive radio (CR) enabled devices can self-organize to form a tactical mesh network and operate on non-dedicated (secondary) spectrum. Each node in the network constantly senses the environment and maintains an up-to-date spectrum usage report. This report is used by a central controller (CC) to initialize the network formation. Then the other CR nodes gradually...
An inherent assumption for packet forwarding in ad hoc networks is that the nodes will cooperate i.e., nodes can rely in each other. Thus, it is extremely important that cooperation is induced and achieved in the network. In this paper, we use game theory to analyze the necessary and sufficient conditions to enforce cooperation enforced, especially when a node cannot perfectly monitor other nodespsila...
Unlike general purpose systems, distributed and embedded control systems, such as power grid control systems and water treatment systems, etc., generally have a 24x7 availability requirement. Hence, upgrading or adding new cyber protection features into these systems in order to sustain them when faults caused by cyber attacks occur, is often difficult to achieve and inhibits the evolution of these...
Most supervisory control and data acquisition (SCADA) systems have been in operation for decades and they in general have 24times7 availability requirement, hence upgrading or adding new fault tolerant logic into the systems to sustain faults caused by cyber attacks when these systems evolve into a cyber environment is often difficult to achieve. In the proposed approach, an external coordination...
Nowadays, wireless service providers are using a mix of access technologies to cater to the wide variety of services having varied QoS requirements. Users, on the other hand, use multi-mode terminals to connect to the networks that are operated by competing service providers. In near-future, users will select the providers on a session-by-session basis based on the price offered and the QoS assurance...
Several factors contribute towards the delay performance in a distributed ad hoc network. One such factor is the probability at which individual nodes attempt to access the shared medium. Moreover, the lack of coordination among the nodes make it even more difficult to predict the delay performance of the system. A node's decision whether to transmit a packet or not, determines not only the expected...
Quality of Service (QoS) of disadvantaged networks is considered from a purely network standpoint in existing works. Adversarial intervention in such networks is not analyzed, nor is it possible to infer if a QoS loss is benign or otherwise. In this paper, we present a QoS loss inference module, where the end nodes can infer the nature of a QoS loss in a non-intrusive manner. The objective of this...
The focus of this paper is on vulnerabilities which exist in supervisory control and data acquisition (SCADA) systems. Cyber attacks targeting weaknesses in these systems can seriously degrade the survivability of a critical system. Detailed here is a non-intrusive approach for improving the survivability of these systems without interruption of their normal process flow. In a typical SCADA system,...
The paper presents a coordination model that contains three active entities: actors, roles and coordinators. Actors abstract the system's functionalities; while roles and coordinators statically encapsulate coordination constraints and dynamically propagate these constraints among themselves and onto the actors. Software system's attack-tolerance and survivability in open hostile environments are...
Masquerading or impersonation attack refers to the illegitimate activity on a computer system when one user impersonates another user. Masquerade attacks are serious in nature due to the fact that they are mostly carried by insiders and thus are extremely difficult to detect. Detection of these attacks is done by monitoring significant changes in user's behavior based on his/her profile. Currently,...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.