24 research outputs found
Detection and Mitigation of Cyber Attacks on Time Synchronization Protocols for the Smart Grid
The current electric grid is considered as one of the greatest engineering achievements of the twentieth century. It has been successful in delivering power to consumers for decades. Nevertheless, the electric grid has recently experienced several blackouts that raised several concerns related to its availability and reliability. The aspiration to provide reliable and efficient energy, and contribute to environment protection through the increasing utilization of renewable energies are driving the need to deploy the grid of the future, the smart grid. It is expected that this grid will be self-healing from power disturbance events, operating resiliently against physical and cyber attack, operating efficiently, and enabling new products and services. All these call for a grid with more Information and Communication Technologies (ICT). As such, power grids are increasingly absorbing ICT technologies to provide efficient, secure and reliable two-way communication to better manage, operate, maintain and control electric grid components.
On the other hand, the successful deployment of the smart grid is predicated on the ability to secure its operations. Such a requirement is of paramount importance especially in the presence of recent cyber security incidents. Furthermore, those incidents are subject to an augment with the increasing integration of ICT technologies and the vulnerabilities they introduce to the grid. The exploitation of these vulnerabilities might lead to attacks that can, for instance, mask the system observability and initiate cascading failures resulting in undesirable and severe consequences.
In this thesis, we explore the security aspects of a key enabling technology in the smart grid, accurate time synchronization. Time synchronization is an immense requirement across the domains of the grid, from generation to transmission, distribution, and consumer premises. We focus on the substation, a basic block of the smart grid system, along with its recommended time synchronization mechanism - the Precision Time Protocol (PTP) - in order to address threats associated with PTP, and propose practical and efficient detection, prevention, mitigation techniques and methodologies that will harden and enhance the security and usability of PTP in a substation. In this respect, we start this thesis with a security assessment of PTP that identifies PTP security concerns, and then address those concerns in the subsequent chapters. We tackle the following main threats associated with PTP: 1) PTP vulnerability to fake timestamp injection through a compromised component 2) PTP vulnerability to the delay attack and 3) The lack of a mechanism that secures the PTP network. Next, and as a direct consequence of the importance of time synchronization in the smart grid, we consider the wide area system to demonstrate the vulnerability of relative data alignment in Phasor Data Concentrators to time synchronization attacks. These problems will be extensively studied throughout this thesis, followed by discussions that highlight open research directions worth further investigations
Recommended from our members
Dr. Robert H. Goddard.
There are four main objectives regarding Dr. Robert H. Goddard in the IQP. The first objective is to develop an understanding of how important Dr. Robert H. Goddard's contribution to the field of rocketry was. The second objective is to determine the impact that Goddard has had on the Worcester community and the community of Roswell, NM. The next objective is to analyze the books written about Goddard. These will also be compared to the number of books written about other popular figures in the aerospace field. The fourth and final objective will be to determine literacy of Goddard's scientific work among Worcester college students
Human CD8+ CD25 + CD127 low regulatory T cells: microRNA signature and impact on TGF-β and IL-10 expression.
Regulatory T cells (Tregs) are central for maintaining immune balance and their dysfunction drives the expansion of critical immunologic disorders. During the past decade, microRNAs (miRNAs) have emerged as potent regulators of gene expression among which immune-related genes and their immunomodulatory properties have been associated with different immune-based diseases. The miRNA signature of human peripheral blood (PB) CD8+ CD25 + CD127 low Tregs has not been described yet. We thus identified, using TaqMan low-density array (TLDA) technique followed by individual quantitative real-time polymerase chain reaction (qRT-PCR) confirmation, 14 miRNAs, among which 12 were downregulated whereas two were upregulated in CD8 + CD25 + CD127 low Tregs in comparison to CD8 + CD25 - T cells. In the next step, microRNA Data Integration Portal (mirDIP) was used to identify potential miRNA target sites in the 3'-untranslated region (3'-UTR) of key Treg cell-immunomodulatory genes with a special focus on interleukin 10 (IL-10) and transforming growth factor β (TGF-β). Having identified potential miR target sites in the 3'-UTR of IL-10 (miR-27b-3p and miR-340-5p) and TGF-β (miR-330-3p), we showed through transfection and transduction assays that the overexpression of two underexpressed miRNAs, miR-27b-3p and miR-340-5p, downregulated IL-10 expression upon targeting its 3'-UTR. Similarly, overexpression of miR-330-3p negatively regulated TGF-β expression. These results highlighted an important impact of the CD8 + Treg mirnome on the expression of genes with significant implication on immunosuppression. These observations could help in better understanding the mechanism(s) orchestrating Treg immunosuppressive function toward unraveling new targets for treating autoimmune pathologies and cancer.SCOPUS: ar.jinfo:eu-repo/semantics/publishe