6,456 research outputs found

    TrusNet: Peer-to-Peer Cryptographic Authentication

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    Originally, the Internet was meant as a general purpose communication protocol, transferring primarily text documents between interested parties. Over time, documents expanded to include pictures, videos and even web pages. Increasingly, the Internet is being used to transfer a new kind of data which it was never designed for. In most ways, this new data type fits in naturally to the Internet, taking advantage of the near limit-less expanse of the protocol. Hardware protocols, unlike previous data types, provide a unique set security problem. Much like financial data, hardware protocols extended across the Internet must be protected with authentication. Currently, systems which do authenticate do so through a central server, utilizing a similar authentication model to the HTTPS protocol. This hierarchical model is often at odds with the needs of hardware protocols, particularly in ad-hoc networks where peer-to-peer communication is prioritized over a hierarchical model. Our project attempts to implement a peer-to-peer cryptographic authentication protocol to be used to protect hardware protocols extending over the Internet. The TrusNet project uses public-key cryptography to authenticate nodes on a distributed network, with each node locally managing a record of the public keys of nodes which it has encountered. These keys are used to secure data transmission between nodes and to authenticate the identities of nodes. TrusNet is designed to be used on multiple different types of network interfaces, but currently only has explicit hooks for Internet Protocol connections. As of June 2016, TrusNet has successfully achieved a basic authentication and communication protocol on Windows 7, OSX, Linux 14 and the Intel Edison. TrusNet uses RC-4 as its stream cipher and RSA as its public-key algorithm, although both of these are easily configurable. Along with the library, TrusNet also enables the building of a unit testing suite, a simple UI application designed to visualize the basics of the system and a build with hooks into the I/O pins of the Intel Edison allowing for a basic demonstration of the system

    The active microbial community more accurately reflects the anaerobic digestion process: 16S rRNA (gene) sequencing as a predictive tool

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    Background: Amplicon sequencing methods targeting the 16S rRNA gene have been used extensively to investigate microbial community composition and dynamics in anaerobic digestion. These methods successfully characterize amplicons but do not distinguish micro-organisms that are actually responsible for the process. In this research, the archaeal and bacterial community of 48 full-scale anaerobic digestion plants were evaluated on DNA (total community) and RNA (active community) level via 16S rRNA (gene) amplicon sequencing. Results: A significantly higher diversity on DNA compared with the RNA level was observed for archaea, but not for bacteria. Beta diversity analysis showed a significant difference in community composition between the DNA and RNA of both bacteria and archaea. This related with 25.5 and 42.3% of total OTUs for bacteria and archaea, respectively, that showed a significant difference in their DNA and RNA profiles. Similar operational parameters affected the bacterial and archaeal community, yet the differentiating effect between DNA and RNA was much stronger for archaea. Co-occurrence networks and functional prediction profiling confirmed the clear differentiation between DNA and RNA profiles. Conclusions: In conclusion, a clear difference in active (RNA) and total (DNA) community profiles was observed, implying the need for a combined approach to estimate community stability in anaerobic digestion

    Securing critical utility systems & network infrastructures

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    Tese de mestrado, Segurança Informática, Universidade de Lisboa, Faculdade de Ciências, 2009As infra-estruturas críticas de TI para serviços públicos são apoiadas por inúmeros sistemas complexos. Estes sistemas permitem a gestão e recolha de informação em tempo-real, constituindo a base para a gestão eficiente das operações. A utilização, cada vez mais frequente, de software e hardware (Commercial Off-The-Shelf, COTS) em sistemas SCADA permitiu grandes beneficios financeiros na aquisição e desenvolvimento de soluções técnicas que suportam os serviços públicos. O uso de hardware e software COTS em sistemas SCADA transferiu para as infra-estruturas críticas os problemas de segurança de uma infraestrutura de TI empresarial. Neste contexto, um desafio para as equipas de gestão operacional dos sistemas de TI é a gestão eficaz dos sistemas e redes que compõem as infra-estruturas críticas dos serviços públicos. Apesar de estas organizações adoptarem, cada vez mais, normas e melhores práticas que visam melhorar a gestão, operações e processos de configuração. Este projecto de investigação propõe-se a desenvolver um estudo comparativo de plataformas de gestão integrada no contexto dos sistemas SCADA que suportam serviços públicos. Adicionalmente, este projecto de investigação irá desenvolver estudos acerca de perfis operacionais dos Sistemas Operativos que suportam a infra-estrutura IT dos serviços públicos críticos. Este projecto de investigação irá descrever como as decisões estratégicas de gestão têm impacto nas operações de gestão de uma infra-estrutura TI.Modern critical utility IT infrastructures are supported by numerous complex systems. These systems allow real-time management and information collection, which is the basis of efficient service management operations. The usage of commercial off-the-shelf (COTS) hardware and software in SCADA systems allowed for major financial advantages in purchasing and developing technical solutions. On the other hand, this COTS hardware and software generalized usage in SCADA systems, exposed critical infrastructures to the security problems of a corporate IT infrastructure. A significant challenge for IT teams is managing critical utility IT infrastructures even upon adopting security best practices that help management, operations and configuration of the systems and network components that comprise those infrastructures. This research project proposes to survey integrated management software that can address the specific security constraints of a SCADA infrastructure supported by COTS software. Additionally, this research project proposes to investigate techniques that will allow the creation of operational profiles of Operating Systems supporting critical utility IT infrastructures. This research project will describe how the strategic management decisions impact tactical operations management of an IT environment. We will investigate desirable technical management elements in support of the operational management

    Residential distributed generation : decision support software to evaluate opportunities in the residential market : a thesis submitted in partial fulfilment of the requirement for the degree of Masters of Engineering at Massey University, Palmerston North, New Zealand /

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    The residential market in New Zealand consumes a significant proportion of our electricity production and is one of the fastest growing sectors. As a vertically integrated generator retailer in the New Zealand electricity industry, Meridian Energy Ltd is concerned at retaining and growing their customer base. They recognise that utilisation of emerging distributed generation [DG] technologies can provide a competitive advantage in the market place. A decision tool was developed to help Meridian identify opportunities within the residential market for applications of DG. The model compares the cost to serve a household's energy needs using a business as usual case with a DG case on an annual basis for a single household or a neighbourhood. A modular approach was used for ease of development and to enable future enhancements. The main modules were: load profile development, DG technology, operation control, costing and a calculation engine. The load profile module estimated space heating/cooling, water heating and other electrical loads for each 30 minute period for 8 representative days of a year based on national end-use statistics and a set of 40 reference profiles. A Gamma distribution was used to simulate diversity between houses. The calculation engine computed the amount of demand that could be met by the DG technologies and hence the residual demand or surplus for export. The pricing module estimated the annual cost including aspects such as: capital cost, fuel cost, maintenance, value of export and cost of import. The technology modules allowed different DG technologies, as well as a range of parameters to be selected. It included renewable energy resource modelling. The performance module allowed different operation control of the heat engine technologies including: base load, electrical peaking, heat peaking, load following (heat-led) and load following(electricity-led). The model was implemented using Microsoft Visual Basic for Applications, in Excel. A series of user-forms were developed to enable the model to be run with a minimum of user input. Three case studies were undertaken. In the first, five technology types were modelled, with the heat pump and Stirling engine looking the most promising. The second case study involved these two technologies in a Christchurch urban area study. A hypothetical network analysis showed the benefit that these technologies could have in reducing peak loading on the network. The third case study examined the sensitivity of the results to the value of specific variables. Load size and capital cost had the strongest influence on NPV

    Corporate data quality management in context

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    Presently, we are well aware that poor quality data is costing large amounts of money to corporations all over the world. Nevertheless, little research has been done about the way Organizations are dealing with data quality management and the strategies they are using. This work aims to find some answers to the following questions: which business drivers motivate the organizations to engage in a data quality management initiative?, how do they implement data quality management? and which objectives have been achieved, so far? Due to the kind of research questions involved, a decision was made to adopt the use of multiple exploratory case studies as research strategy [32]. The case studies were developed in a telecommunications company (MyTelecom), a public bank (PublicBank) and in the central bank (CentralBank) of one European Union Country. The results show that the main drivers to data quality (DQ) initiatives were the reduction in non quality costs, risk management, mergers, and the improvement of the company's image among its customers, those aspects being in line with literature [7, 8, 20]. The commercial corporations (MyTelecom and PublicBank) began their DQ projects with customer data, this being in accordance with literature [18], while CentralBank, which mainly works with analytical systems, began with data source metadata characterization and reuse. None of the organizations uses a formal DQ methodology, but they are using tools for data profiling, standardization and cleaning. PublicBank and CentralBank are working towards a Corporate Data Policy, aligned with their Business Policy, which is not the case of MyTelecom. The findings enabled us to prepare a first draft of a "Data Governance strategic impact grid", adapted from Nolan& MacFarlan IT Governance strategic impact grid [17], this framework needing further empirical support
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