6,422 research outputs found
A Survey on Communication Networks for Electric System Automation
Published in Computer Networks 50 (2006) 877–897, an Elsevier journal. The definitive version of this publication is available from Science Direct. Digital Object Identifier:10.1016/j.comnet.2006.01.005In today’s competitive electric utility marketplace, reliable and real-time information become the key factor for reliable delivery of power to the end-users, profitability of the electric utility and customer satisfaction. The operational and commercial demands of electric utilities require a high-performance data communication network that supports both existing functionalities and future operational requirements. In this respect, since such a communication network constitutes the core of the electric system automation applications, the design of a cost-effective and reliable network architecture is crucial.
In this paper, the opportunities and challenges of a hybrid network architecture are discussed for electric system automation.
More specifically, Internet based Virtual Private Networks, power line communications, satellite communications and wireless communications (wireless sensor networks, WiMAX and wireless mesh networks) are described in detail. The motivation of this paper is to provide a better understanding of the hybrid network architecture that can provide heterogeneous electric system automation application requirements. In this regard, our aim is to present a structured framework for electric utilities who plan to utilize new communication technologies for automation and hence, to make the decision making process more effective and direct.This work was supported by NEETRAC under
Project #04-157
Internet Censorship: An Integrative Review of Technologies Employed to Limit Access to the Internet, Monitor User Actions, and their Effects on Culture
The following conducts an integrative review of the current state of Internet Censorship in China, Iran, and Russia, highlights common circumvention technologies (CTs), and analyzes the effects Internet Censorship has on cultures. The author spends a large majority of the paper delineating China’s Internet infrastructure and prevalent Internet Censorship Technologies/Techniques (ICTs), paying particular attention to how the ICTs function at a technical level. The author further analyzes the state of Internet Censorship in both Iran and Russia from a broader perspective to give a better understanding of Internet Censorship around the globe. The author also highlights specific CTs, explaining how they function at a technical level. Findings indicate that among all three nation-states, state control of Internet Service Providers is the backbone of Internet Censorship. Specifically, within China, it is discovered that the infrastructure functions as an Intranet, thereby creating a closed system. Further, BGP Hijacking, DNS Poisoning, and TCP RST attacks are analyzed to understand their use-case within China. It is found that Iran functions much like a weaker version of China in regards to ICTs, with the state seemingly using the ICT of Bandwidth Throttling rather consistently. Russia’s approach to Internet censorship, in stark contrast to Iran and China, is found to rely mostly on the legislative system and fear to implement censorship, though their technical level of ICT implementation grows daily. TOR, VPNs, and Proxy Servers are all analyzed and found to be robust CTs. Drawing primarily from the examples given throughout the paper, the author highlights the various effects of Internet Censorship on culture – noting that at its core, Internet Censorship destroys democracy
Economic Development Potential through IP Telephony for Namibia
IP telephony, economic growth, telecommunications, ICT, Granger causality, Namibia
Experimentation with MANETs of Smartphones
Mobile AdHoc NETworks (MANETs) have been identified as a key emerging
technology for scenarios in which IEEE 802.11 or cellular communications are
either infeasible, inefficient, or cost-ineffective. Smartphones are the most
adequate network nodes in many of these scenarios, but it is not
straightforward to build a network with them. We extensively survey existing
possibilities to build applications on top of ad-hoc smartphone networks for
experimentation purposes, and introduce a taxonomy to classify them. We present
AdHocDroid, an Android package that creates an IP-level MANET of (rooted)
Android smartphones, and make it publicly available to the community.
AdHocDroid supports standard TCP/IP applications, providing real smartphone
IEEE 802.11 MANET and the capability to easily change the routing protocol. We
tested our framework on several smartphones and a laptop. We validate the MANET
running off-the-shelf applications, and reporting on experimental performance
evaluation, including network metrics and battery discharge rate.Comment: 6 pages, 7 figures, 1 tabl
A Comparative Usability Study of Two-Factor Authentication
Two-factor authentication (2F) aims to enhance resilience of password-based
authentication by requiring users to provide an additional authentication
factor, e.g., a code generated by a security token. However, it also introduces
non-negligible costs for service providers and requires users to carry out
additional actions during the authentication process. In this paper, we present
an exploratory comparative study of the usability of 2F technologies. First, we
conduct a pre-study interview to identify popular technologies as well as
contexts and motivations in which they are used. We then present the results of
a quantitative study based on a survey completed by 219 Mechanical Turk users,
aiming to measure the usability of three popular 2F solutions: codes generated
by security tokens, one-time PINs received via email or SMS, and dedicated
smartphone apps (e.g., Google Authenticator). We record contexts and
motivations, and study their impact on perceived usability. We find that 2F
technologies are overall perceived as usable, regardless of motivation and/or
context of use. We also present an exploratory factor analysis, highlighting
that three metrics -- ease-of-use, required cognitive efforts, and
trustworthiness -- are enough to capture key factors affecting 2F usability.Comment: A preliminary version of this paper appears in USEC 201
- …