746 research outputs found
Optimal Detection of Faulty Traffic Sensors Used in Route Planning
In a smart city, real-time traffic sensors may be deployed for various
applications, such as route planning. Unfortunately, sensors are prone to
failures, which result in erroneous traffic data. Erroneous data can adversely
affect applications such as route planning, and can cause increased travel
time. To minimize the impact of sensor failures, we must detect them promptly
and accurately. However, typical detection algorithms may lead to a large
number of false positives (i.e., false alarms) and false negatives (i.e.,
missed detections), which can result in suboptimal route planning. In this
paper, we devise an effective detector for identifying faulty traffic sensors
using a prediction model based on Gaussian Processes. Further, we present an
approach for computing the optimal parameters of the detector which minimize
losses due to false-positive and false-negative errors. We also characterize
critical sensors, whose failure can have high impact on the route planning
application. Finally, we implement our method and evaluate it numerically using
a real-world dataset and the route planning platform OpenTripPlanner.Comment: Proceedings of The 2nd Workshop on Science of Smart City Operations
and Platforms Engineering (SCOPE 2017), Pittsburgh, PA USA, April 2017, 6
page
Hierarchical Kohonenen Net for Anomaly Detection in Network Security
A novel multilevel hierarchicalKohonen Net (K-Map) for an intrusion detection system is presented. Each level of the hierarchical map is modeled as a simple winner-take-all K-Map. One significant advantage of this multilevel hierarchical K-Map is its computational efficiency. Unlike other statistical anomaly detection methods such as nearest neighbor approach, K-means clustering or probabilistic analysis that employ distance computation in the feature space to identify the outliers, our approach does not involve costly point-to-point computation in organizing the data into clusters. Another advantage is the reduced network size. We use the classification capability of the K-Map on selected dimensions of data set in detecting anomalies. Randomly selected subsets that contain both attacks and normal records from the KDD Cup 1999 benchmark data are used to train the hierarchical net. We use a confidence measure to label the clusters. Then we use the test set from the same KDD Cup 1999 benchmark to test the hierarchical net. We show that a hierarchical K-Map in which each layer operates on a small subset of the feature space is superior to a single-layer K-Map operating on the whole feature space in detecting a variety of attacks in terms of detection rate as well as false positive rate
Securing industrial control system environments: the missing piece
Cyberattacks on industrial control systems (ICSs) are no longer matters of anticipation. These systems are continually subject to malicious attacks without much resistance. Network breaches, data theft, denial of service, and command and control functions are examples of common attacks on ICSs. Despite available security solutions, safety, security, resilience, and performance require both private public sectors to step-up strategies to address increasing security concerns on ICSs. This paper reviews the ICS security risk landscape, including current security solution strategies in order to determine the gaps and limitations for effective mitigation. Notable issues point to a greater emphasis on technology security while discounting people and processes attributes. This is clearly incongruent with; emerging security risk trends, the biased security strategy of focusing more on supervisory control and data acquisition systems, and the emergence of more sector-specific solutions as against generic security solutions. Better solutions need to include approaches that follow similar patterns as the problem trend. These include security measures that are evolutionary by design in response to security risk dynamics. Solutions that recognize and include; people, process and technology security enhancement into asingle system, and addressing all three-entity vulnerabilities can provide a better solution for ICS environments
Impact Assessment of Hypothesized Cyberattacks on Interconnected Bulk Power Systems
The first-ever Ukraine cyberattack on power grid has proven its devastation
by hacking into their critical cyber assets. With administrative privileges
accessing substation networks/local control centers, one intelligent way of
coordinated cyberattacks is to execute a series of disruptive switching
executions on multiple substations using compromised supervisory control and
data acquisition (SCADA) systems. These actions can cause significant impacts
to an interconnected power grid. Unlike the previous power blackouts, such
high-impact initiating events can aggravate operating conditions, initiating
instability that may lead to system-wide cascading failure. A systemic
evaluation of "nightmare" scenarios is highly desirable for asset owners to
manage and prioritize the maintenance and investment in protecting their
cyberinfrastructure. This survey paper is a conceptual expansion of real-time
monitoring, anomaly detection, impact analyses, and mitigation (RAIM) framework
that emphasizes on the resulting impacts, both on steady-state and dynamic
aspects of power system stability. Hypothetically, we associate the
combinatorial analyses of steady state on substations/components outages and
dynamics of the sequential switching orders as part of the permutation. The
expanded framework includes (1) critical/noncritical combination verification,
(2) cascade confirmation, and (3) combination re-evaluation. This paper ends
with a discussion of the open issues for metrics and future design pertaining
the impact quantification of cyber-related contingencies
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