Documentation Assessment of the Diebold Voting System

The California Secretary of State commissioned a comprehensive, independent evaluation of the electronic voting systems certified for use within the State. This team, working as part of the “Top to Bottom” Review (“TTBR”), evaluated the documentation supplied by Diebold Election System, Inc

Coupling of a Powerline Communication Modem to an Industrial Fieldbus Network

In a broad and heterogeneous industrial communications environment, the need of having flexibility as well as maintaining the reliability and low cost has pushed the researchers to look for new possibilities and market opportunities to cover all the needs. Actual industrial systems are needed of at least two ways of inputs: power input, for the system operation, and data input for controlling, testing and administrating the system. The main restrictions, that actual systems and networks have, are low flexibility and, sometimes, considerable expenses in terms on maintenance. But also they have advantages, e.g. low response time, high reliability, wide and highly known architecture etc. In this background, grows the thought of increasing the flexibility without impacting such important aspects as response time or reliability. On the industrial communication protocols, Ethernet POWERLINK standard is one of the existing protocols in the market. Ethernet POWERLINK is a real-time industrial communication protocol based on Ethernet standard, which is used for controlling and commanding several sensors and actuators with high speed, time-synchronization and reliability, minimizing the global system latency. The main aim of this project is to reach a balanced solution by joining both power and data inputs in just one cable that allows an increase in the flexibility, as well as decrease in the maintenance costs, restraining the response time and achieving compatibility with a wide spread standard as is Ethernet.Puche Planells, J. (2014). Coupling of a Powerline Communication Modem to an Industrial Fieldbus Network. http://hdl.handle.net/10251/46618.Archivo delegad

Real-time communications over wired/wireless PROFIBUS networks supporting inter-cell mobility

PROFIBUS is an international standard (IEC 61158, EN 50170) for factory-floor communications, with several thousands of installations worldwide. Taking into account the increasing need for mobile devices in industrial environments, one obvious solution is to extend traditional wired PROFIBUS networks with wireless capabilities. In this paper, we outline the major aspects of a hybrid wired/wireless PROFIBUS-based architecture, where most of the design options were made in order to guarantee the real-time behaviour of the overall network. We also introduce the timing unpredictability problems resulting from the co-existence of heterogeneous physical media in the same network. However, the major focus of this paper is on how to guarantee real-time communications in such a hybrid network, where nodes (and whole segments) can move between different radio cells (inter-cell mobility). Assuming a simple mobility management mechanism based on mobile nodes performing periodic radio channel assessment and switching, we propose a methodology to compute values for specific parameters that enable an optimal (minimum) and bounded duration of the handoff procedure

Communication Infrastructures for Distributed Control of Power Distribution Networks

Accepted versio

Amazon Web Services (AWS) Cloud Platform for Satellite Data Processing

As part of NOAA’s Environmental Satellite Processing and Distribution System (ESPDS) program, Solers created a cloud platform for satellite data management and processing. It consists of Enterprise Data Management (EDM) and Enterprise Product Generation (EPG) services, hosted in an Amazon Web Services (AWS) cloud environment, leveraging AWS cloud services and existing NOAA product generation algorithms. While this cloud platform was developed in the context of NOAA/NESDIS satellite data management and processing requirements, it also has tremendous applicability and cost effectiveness for small satellite data management and processing needs. An attractive method for ingesting data from small satellites is the AWS Ground Station. This can help small satellite operators save on costs of real estate, hardware/software, and labor to deploy and operate their own ground stations. The data is ingested via AWS-managed antennas, and made available for further processing in the AWS cloud using COTS RF/ baseband over IP transport services. Once this data has been ingested and made available, the flexible REST APIs from the EDM and EPG services in the AWS cloud make it easy and cost-effective for small satellite operators to catalog and process the data into consumable products, and make them available for access to end users

DOWNSTREAM RESOURCE ALLOCATION IN DOCSIS 3.0 CHANNEL BONDED NETWORKS

Modern broadband internet access cable systems follow the Data Over Cable System Interface Specification (DOCSIS) for data transfer between the individual cable modem (CM) and the Internet. The newest version of DOCSIS, version 3.0, provides an abstraction referred to as bonding groups to help manage bandwidth and to increase bandwidth to each user beyond that available within a single 6MHz. television channel. Channel bonding allows more than one channel to be used by a CM to provide a virtual channel of much greater bandwidth. This combining of channels into bonding groups, especially when channels overlap between more than one bonding group, complicates the resource allocation problem within these networks. The goal of resource allocation in this research is twofold, to provide for fairness among users while at the same time making maximum possible utilization of the available system bandwidth. The problem of resource allocation in computer networks has been widely studied by the academic community. Past work has studied resource allocation in many network types, however application in a DOCSIS channel bonded network has not been explored. This research begins by first developing a definition of fairness in a channel bonded system. After providing a theoretical definition of fairness we implement simulations of different scheduling disciplines and evaluate their performance against this theoretical ideal. The complexity caused by overlapped channels requires even the simplest scheduling algorithms to be modified to work correctly. We then develop an algorithm to maximize the use of the available system bandwidth. The approach involves using competitive analysis techniques and an online algorithm to dynamically reassign flows among the available channels. Bandwidth usage and demand requests are monitored for bandwidth that is underutilized, and demand that is unsatisfied, and real time changes are made to the flow-to-channel mappings to improve the utilization of the total available bandwidth. The contribution of this research is to provide a working definition of fairness in a channel bonded environment, the implementation of several scheduling disciplines and evaluation of their adherence to that definition, and development of an algorithm to improve overall bandwidth utilization of the system

PERFORMANCE OF VOIP SERVICES ON A DOCSIS NETWORK TARGETED BY A DENIAL OF SERVICE ATTACK

Over 48 million end users worldwide utilize cable modems as their means of accessing the Internet at high speeds. The United States accounts for 54% of those users. Networks which provide access via cable modems utilize Data Over Cable Service Interface Specifications (DOCSIS) as their means of network management. As availability to the Internet increases (especially at high speeds supported by broadband access), so does the opportunity for malicious activity against users utilizing the Internet. Denial-of-service (DoS) attacks are one form of malicious activity and one of the most common. In commonplace Ethernet-based wired networks, a DoS attack requires relatively high levels of computing and network resources to successfully deny service. In DOCSIS-based networks, high levels of computing and network resources aren\u27t mandatory in order to sufficiently degrade a network segment, especially when the objective of the attack is to reduce the quality of Voice over Internet Protocol (VoIP) sessions. This phenomenon hinges on the Media Access Control layer protocol employed by DOCSIS used for managing access to the upstream transmission medium. Utilizing NS, a discrete event network simulator, we define and analyze a DoS attack that specifically targets DOCSISbased networks. The attack consumes a small portion of the downstream bandwidth available over a cable network but can severely impact upstream performance. While the DoS attack can have any objective, we focus on an attack on best effort VoIP sessions. The implications of this phenomenon are widespread as end users looking for cost-saving voice telecommunications services migrate to best effort VoIP such as provided by Vonage. The iii contribution of this research is the formulation of a DoS attack that exploits the relatively inefficient upstream channel in a DOCSIS system and analysis of the attack which explores the impact of the two attack parameters on VoIP performance. Those two attack parameters are the number of nodes attacked and the frequency at which each node is attacked