Check for updates Assessing the Impact of DNS Configuration
- Authors: Okuthe, J A , Terzoli, Alfredo
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430917 , vital:72727 , https://doi.org/10.1007/978-3-031-34896-9
- Description: Domain name system (DNS) is an essential enabler for connecting us-ers and services on the Internet. DNS translates human readable do-main names into IP addresses and precedes client connection to a server via a domain name. DNS service is therefore expected to con-sume network bandwidth even though it offers no direct benefit to the user. Having observed the large component of DNS traffic on the com-munity network local loop in our previous study, we migrated the DNS service from a server on the LAN to the gateway router and reconfig-ured the cache time-to-live. Results from the analysis of network traffic captured from the gateway router interface show a 26% decrease in the downlink bandwidth utilization and 46% decline in the uplink bandwidth utilization. The DNS component of the local loop traffic reduces from 45.28% to 4.11%. On the other hand, the Web component of the local loop traffic increases from 49.42% to 95.49%. Data collected from a mirroring port on the LAN switch indicate a decrease in the DNS portion of the internal traffic from 0.38% to 0.18%. Although the DNS reconfigu-ration helps alleviate network bandwidth constraints and reduces DNS component of the traffic, the Web portion increases. The implementa-tion of effective, efficient and sustainable Web traffic management is therefore required.
- Full Text:
- Date Issued: 2023
Assessing the Impact of DNS Configuration on Low Bandwidth Networks
- Authors: Okuthe, J A , Terzoli, Alfredo
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430903 , vital:72726 , https://doi.org/10.1007/978-3-031-34896-9_6
- Description: Domain name system (DNS) is an essential enabler for connecting us-ers and services on the Internet. DNS translates human readable do-main names into IP addresses and precedes client connection to a server via a domain name. DNS service is therefore expected to con-sume network bandwidth even though it offers no direct benefit to the user. Having observed the large component of DNS traffic on the com-munity network local loop in our previous study, we migrated the DNS service from a server on the LAN to the gateway router and reconfig-ured the cache time-to-live. Results from the analysis of network traffic captured from the gateway router interface show a 26% decrease in the downlink bandwidth utilization and 46% decline in the uplink bandwidth utilization. The DNS component of the local loop traffic reduces from 45.28% to 4.11%. On the other hand, the Web component of the local loop traffic increases from 49.42% to 95.49%. Data collected from a mirroring port on the LAN switch indicate a decrease in the DNS portion of the internal traffic from 0.38% to 0.18%. Although the DNS reconfigu-ration helps alleviate network bandwidth constraints and reduces DNS component of the traffic, the Web portion increases. The implementa-tion of effective, efficient and sustainable Web traffic management is therefore required.
- Full Text:
- Date Issued: 2022
Cultural Seascapes in the ‘Sea of Calms’ and La Restinga Coast
- Authors: De la Cruz-Modino, Raquel , Piñeiro-Corbeira, Cristina , Aswani, Shankar , González-Cruz, Carla , Domínguez, David , Ordóñez García, Paula , Santana-Talavera, Agustín , Pascual-Fernández, José
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/391319 , vital:68641 , ISBN 978-3-031-07289-5 , https://doi.org/10.1007/978-3-031-07289-5
- Description: El Hierro has been characterized by the balance between human development and environmental sustainability. The island was historically far from the mass tourism developments dominant on the other Canary Islands. Tourism accommodations in El Hierro are few compared to more developed coastal areas in the Archipelago, and recreational activities are mainly linked to cultural and natural sites and resources. This chapter focuses on La Restinga fishing village and its coasts, where the ‘Sea of Calms’ and one multiple-use Marine Reserve (MR) are located, both of which became popular over the last decade. The tourist development experience has promoted a new way of looking at the sea and conceptualizing its habitats and populations. In 2014, after the submarine volcano eruption occurred in 2011, we estimated that at least 25,391 dives had been carried out in the diving spots established by the MR and other diving sites close to La Restinga. Despite the difficulties experienced after the volcano eruption, a unique imaginaire has been consolidated, thanks to the image of the island's exclusive nature and iconic elements. In addition, the rapid recovery of the destination is an excellent example of how the tourism system can adapt and incorporate unexpected events such as volcanic eruptions.
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- Date Issued: 2022
Implementing a Content-Based Routing Framework for Application Integration on to Teleweaver Application Server
- Authors: Ngwenya, Sikhumbuzo , Shibeshi, Zelalem S , Terzoli, Alfredo
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430580 , vital:72701 , https://ieeexplore.ieee.org/abstract/document/9576969
- Description: This paper presents an architectural overview of content-based dynam-ic routing for integrating applications on to an application server named TeleWeaver, a middleware platform developed within Siyakhula Living Lab (SLL). SLL is an ICT4D project in the Eastern Cape Province of South Africa. TeleWeaver was created as a mediation layer between software systems developed for use by beneficiaries of the Siyakhula Living Lab. The main challenge with these disparate systems was that they had unnecessary, redundant components; TeleWeaver acts as a common platform that suits the development of many services such as eGovernment, eHealth, and eJudiciary.
- Full Text:
- Date Issued: 2021
Pregnancy Decision Making: Abortion and Adoption
- Authors: Mavuso, Jabulile M-J J , Macleod, Catriona I
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434145 , vital:73034 , ISBN 9781119161899 , https://onlinelibrary.wiley.com/doi/book/10.1002/9781119171492
- Description: Pregnancy decision making encompasses a large range of interactions, including decisions and actions to avoid pregnancy or to become pregnant. This entry addresses the question of decision making regarding the outcome of a pregnancy: abortion or taking the pregnancy to term, with the latter resulting in parenting or adoption placement. Adolescents' pregnancy decision making has been a special area of focus for some decades now, particularly regarding whether adolescents are capable of making termination-of-pregnancy decisions. This entry highlights controversies concerning, first, teenage pregnancy as a social problem; second, risk research that seeks to outline the consequences of various reproductive decisions; third, questions around adolescents' maturity regarding making reproductive decisions; fourth, the reasons provided for various reproductive decisions; and, finally, issues surrounding the autonomy of young pregnant women in their reproductive decisions.
- Full Text:
- Date Issued: 2019
Extending the NFComms framework for bulk data transfers
- Authors: Pennefather, Sean , Bradshaw, Karen L , Irwin, Barry V W
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430152 , vital:72669 , https://doi.org/10.1145/3278681.3278686
- Description: In this paper we present the design and implementation of an indirect messaging extension for the existing NFComms framework that pro-vides communication between a network flow processor and host CPU. This extension addresses the bulk throughput limitations of the frame-work and is intended to work in conjunction with existing communication mediums. Testing of the framework extensions shows an increase in throughput performance of up to 300× that of the current direct mes-sage passing framework at the cost of increased single message laten-cy of up to 2×. This trade-off is considered acceptable as the proposed extensions are intended for bulk data transfer only while the existing message passing functionality of the framework is preserved and can be used in situations where low latency is required for small messages.
- Full Text:
- Date Issued: 2018
Toward distributed key management for offline authentication
- Authors: Linklater, Gregory , Smith, Christian , Herbert, Alan , Irwin, Barry V W
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430283 , vital:72680 , https://doi.org/10.1145/3278681.3278683
- Description: Self-sovereign identity promises prospective users greater control, security, privacy, portability and overall greater convenience; however the immaturity of current distributed key management solutions results in general disregard of security advisories in favour of convenience and accessibility. This research proposes the use of intermediate certificates as a distributed key management solution. Intermediate certificates will be shown to allow multiple keys to authenticate to a single self-sovereign identity. Keys may be freely added to an identity without requiring a distributed ledger, any other third-party service or sharing private keys between devices. This research will also show that key rotation is a superior alternative to existing key recovery and escrow systems in helping users recover when their keys are lost or compromised. These features will allow remote credentials to be used to issuer, present and appraise remote attestations, without relying on a constant Internet connection.
- Full Text:
- Date Issued: 2018
Investigating the effects various compilers have on the electromagnetic signature of a cryptographic executable
- Authors: Frieslaar, Ibraheem , Irwin, Barry V W
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430207 , vital:72673 , https://doi.org/10.1145/3129416.3129436
- Description: This research investigates changes in the electromagnetic (EM) signatures of a cryptographic binary executable based on compile-time parameters to the GNU and clang compilers. The source code was compiled and executed on a Raspberry Pi 2, which utilizes the ARMv7 CPU. Various optimization flags are enabled at compile-time and the output of the binary executable's EM signatures are captured at run-time. It is demonstrated that GNU and clang compilers produced different EM signature on program execution. The results indicated while utilizing the O3 optimization flag, the EM signature of the program changes. Additionally, the g++ compiler demonstrated fewer instructions were required to run the executable; this related to fewer EM emissions leaked. The EM data from the various compilers under different optimization levels was used as input data for a correlation power analysis attack. The results indicated that partial AES-128 encryption keys was possible. In addition, the fewest subkeys recovered was when the clang compiler was used with level O2 optimization. Finally, the research was able to recover 15 of 16 AES-128 cryptographic algorithm's subkeys, from the the Pi.
- Full Text:
- Date Issued: 2017
Issues-Based Enquiry: An Enabling Pedagogy for ESD in Teacher Education and School Geography
- Authors: Wilmot, Diana P
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/436266 , vital:73253 , ISBN 978-3-319-45989-9 , https://doi.org/10.1007/978-3-319-45989-9_10
- Description: This chapter addresses the need for innovations in geography teacher education programmes in a developing world context. More specifically, it responds to the need for practical ‘how to’ examples for ESD integration into school geography by de-scribing a pedagogical experiment that was piloted with in-service Namibian teachers and education development offic-ers (EDOs) enrolled for a Bachelor of Education (Honours) de-gree in 2014. The theoretical constructs underpinning the ex-periment’s design and pedagogical approach as well as the teacher professional development model are described. This is followed by a description and justification of the methodology used to answer the research question: ‘How can issues-based enquiry enable the integration of ESD at the micro level of the classroom?’ The findings of the experiment provide evidence of how issues-based enquiry, underpinned by active learning and constructivist epistemology and a model of teacher pro-fessional development located in reflexive practice, enabled the teachers to acquire foundational knowledge and pedagog-ical content knowledge for effective integration of ESD into school geography. This chapter may offer other teacher educators some guidelines on how to develop teacher capacity to integrate ESD into their own programmes.
- Full Text:
- Date Issued: 2017
TeleWeaver: an architectural overview of a customised application server for rurality
- Authors: Tsietsi, Mosiuoa , Terzoli, Alfredo , Gumbo, Sibukelo
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430624 , vital:72704 , 10.1109/ISTAFRICA.2016.7530616
- Description: The Siyakhula Living Lab in the rural Eastern Cape province of South Africa has been in existence for over a decade now. In this time, sever-al software artefacts have been developed by students and partners with the aim of providing contextually-relevant services to the rural community. However, reliance on different platforms and paradigms has meant that the deployment of such services would be difficult to implement and maintain reliably in actual practice. What is required is a single software platform that can act as a docking station for multiple applications, as well as a routing substrate for applications living inside and outside the platform. A candidate platform to enable this is currently being integrated under the codename Teleweaver and is built from a free, open source J2EE application server and integrates with other software components. This paper provides an architectural overview of the platform and demonstrates how it provides a sustainable context for application development going forward.
- Full Text:
- Date Issued: 2016
A Comparison of Four End-User Devices as Thin Clients for Public Access to the Internet in Poor Communities
- Authors: Duff, Kevin , Siebörger, Ingrid , Terzoli, Alfredo
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430892 , vital:72725 , https://doi.org/10.1007/978-3-319-16886-9_24
- Description: In poor areas, where ICT infrastructure is being deployed with devel-opmental aims, there is a need to provide appropriate, sustainable technologies that meet the needs of the local community. Current trends for ICT interventions favour the use of mobile user equipment, such as tablets and cellphones, but we think that they are inappropriate to allow production as opposed to mainly consumption of digital con-tent, at least for the foreseeable future. Thus our objective is to reduce the cost of deployment of traditional communal Internet Access Points using PCs. In this paper we compare four candidate computers to be used as thin clients in such settings, according to seven different cate-gories. Our study identifies the strengths, weaknesses and problems of each device, and concludes with recommendations for anybody wish-ing to deploy such devices as Linux Terminal Server Project (LTSP) thin clients in a public Internet Access Point.
- Full Text:
- Date Issued: 2015
A reflection on the use of case studies as a methodology for social learning research in sub Saharan Africa
- Authors: Cundill, Georgina , Lotz-Sisitka, Heila , Mukute, Mutizwa , Belay, Million , Shackleton, Sheona , Kulundu, Iinjairu
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/436636 , vital:73288 , ISBN 1573-5214 , https://doi.org/10.1016/j.njas.2013.04.001
- Description: A recent review has highlighted that the methodology most commonly employed to research social learning has been the individual case study. We draw on four examples of social learning research in the environmental and sustainability sci-ences from sub-Saharan Africa to reflect on possible reasons behind the preponderance of case study research in this field, and to identify common elements that may be significant for social learning research more generally. We find that a com-mon interest in change oriented social learning, and therefore processes of change, makes case studies a necessary ap-proach because long term process analyses are required that are sensitive to social-ecological contexts. Common elements of the examples reflected upon included: a focus on initiating, tracking and/or understanding a process of change toward sustainability; long term research; an action research agenda that involves reflecting on data with research participants; and temporal, process based analysis of data coupled with in-depth theoretical analysis. This paper highlights that there is significant scope for exploratory research that compares case studies of social learning research to generate a deeper un-derstanding of social learning processes, and their relationship to human agency and societal change.
- Full Text:
- Date Issued: 2014
Leadership for biodiversity in South Africa transformation and capacity development in the GreenMatter programme
- Authors: Rosenberg, Eureta
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437190 , vital:73351 , ISBN 978-9086862528 , https://doi.org/10.3920/978-90-8686-802-5_18
- Description: As we begin to write this chapter, it is only a few hours since the news broke about the passing of Nelson Mandela, the founding president of a democratic South Africa. As we de-scribe our work in supporting intergenerational learning and the development of transformational leadership, it seems appro-priate to make this reference as a tribute to him. This work would not have been possible without the contribution of Man-dela and all who fought for justice and an egalitarian society in South Africa. We are able to write about the so-called ‘born frees’ because of Mandela’s role in dismantling apartheid, a system that sought to condemn black people to perpetual ser-vitude, ignorance and poverty. Indeed, our efforts in building skills for biodiversity, under the auspices of GreenMatter, are inspired by his courageous leadership, his selflessness, com-mitment to education and love of people, knowledge and na-ture. While philosophies, contexts and methods will vary, the quest of all intergenerational learning is to build a bridge that enables young people to learn from the experiences and wisdom of previous generations.
- Full Text:
- Date Issued: 2014
Real-time distributed malicious traffic monitoring for honeypots and network telescopes
- Authors: Hunter, Samuel O , Irwin, Barry V W , Stalmans, Etienne
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429660 , vital:72630 , 10.1109/ISSA.2013.6641050
- Description: Network telescopes and honeypots have been used with great success to record malicious network traffic for analysis, however, this is often done off-line well after the traffic was observed. This has left us with only a cursory understanding of malicious hosts and no knowledge of the software they run, uptime or other malicious activity they may have participated in. This work covers a messaging framework (rDSN) that was developed to allow for the real-time analysis of malicious traffic. This data was captured from multiple, distributed honeypots and network telescopes. Data was collected over a period of two months from these data sensors. Using this data new techniques for malicious host analysis and re-identification in dynamic IP address space were explored. An Automated Reconnaissance (AR) Framework was developed to aid the process of data collection, this framework was responsible for gathering information from malicious hosts through both passive and active fingerprinting techniques. From the analysis of this data; correlations between malicious hosts were identified based on characteristics such as Operating System, targeted service, location and services running on the malicious hosts. An initial investigation in Latency Based Multilateration (LBM), a novel technique to assist in host re-identification was tested and proved successful as a supporting metric for host re-identification.
- Full Text:
- Date Issued: 2013
Towards a GPU accelerated virtual machine for massively parallel packet classification and filtering
- Authors: Nottingham, Alastair , Irwin, Barry V W
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430295 , vital:72681 , https://doi.org/10.1145/2513456.2513504
- Description: This paper considers the application of GPU co-processors to accelerate the analysis of packet data, particularly within extremely large packet traces spanning months or years of traffic. Discussion focuses on the construction, performance and limitations of the experimental GPF (GPU Packet Filter), which employs a prototype massively-parallel protocol-independent multi-match algorithm to rapidly compare packets against multiple arbitrary filters. The paper concludes with a consideration of mechanisms to expand the flexibility and power of the GPF algorithm to construct a fully programmable GPU packet classification virtual machine, which can perform massively parallel classification, data-mining and data-transformation to explore and analyse packet traces. This virtual machine is a component of a larger framework of capture analysis tools which together provide capture indexing, manipulation, filtering and visualisation functions.
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- Date Issued: 2013
Capturefoundry: a gpu accelerated packet capture analysis tool
- Authors: Nottingham, Alastair , Richter, John , Irwin, Barry V W
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430112 , vital:72666 , https://doi.org/10.1145/2389836.2389877
- Description: Packet captures are used to support a variety of tasks, including network administration, fault diagnosis and security and network related research. Despite their usefulness, processing packet capture files is a slow and tedious process that impedes the analysis of large, long-term captures. This paper discusses the primary components and observed performance of CaptureFoundry, a stand-alone capture analysis support tool designed to quickly map, filter and extract packets from large capture files using a combination of indexing techniques and GPU accelerated packet classification. All results are persistent, and may be used to rapidly extract small pre-filtered captures on demand that may be analysed quickly in existing capture analysis applications. Performance results show that CaptureFoundry is capable of generating multiple indexes and classification results for large captures at hundreds of megabytes per second, with minimal CPU and memory overhead and only minor additional storage space requirements.
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- Date Issued: 2012
Living lab methodology as an approach to innovation in ICT4D: The Siyakhula Living Lab experience
- Authors: Gumbo, Sibukelo , Thinyane, Hannah , Thinyane, Mamello , Terzoli, Alfredo , Hansen, Susan
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431302 , vital:72762 , https://www.siyakhulall.com/sites/default/files/ISTAfrica_Paper_ref_18_doc_4809_0.pdf
- Description: Underdevelopment and poverty represent key challenges faced by the modern world, which have attracted the attention of NGOs, civil society, government and multinationals. Various undertakings including the United Nations Millennium Development Goals articulation and the World Summit on Information Society highlight the global commitment towards addressing these problems. The solutions to these problems should be derived out of well-structured innovation systems that take into consideration the grassroot context and concerns. A number of in-novation models have been formulated and utilized effectively in differ-ent industries, and some of these have equally been used effectively in community development contexts. This paper elaborates on the Living Lab methodology and its application in ICT4D contexts, highlighting the effectiveness of this model towards integrating end-users within their problem solving effort. This is discussed through the backdrop of the Siyakhula Living Lab, an ICT4D intervention. The embedding environ-ment for this model, which enables key synergies with other stakehold-ers, is also discussed.
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- Date Issued: 2012
Identifying annotations for adventure game generation from fiction text
- Authors: Berkland, Ross , Bangay, Shaun D
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433366 , vital:72965 , https://doi.org/10.1145/1899503.1899506
- Description: Recent advancements in Text-to-Scene research have lead to the devel-opment of systems which automatically extract key concepts from the text of a fiction book and generate computer animated movies depicting the sto-ry. Extracting such annotations from raw fiction text is a laborious process and so in this work we evaluate appropriate candidates to serve as the basis for the required annotations for generating interactive virtual worlds. We val-idate our choice by generating adventure games: interactive virtual worlds which create a stylized representation of the environment described in the text, populate it with characters related to the story and define game goals related to the plot of the fiction story. Our prototype produces a fully playa-ble game, making use of an existing open-source game engine. The pro-cess is evaluated using user tests in which participants are asked to meas-ure the accuracy with which the game represents the events, characters and goals described in the story. The response indicates that the chosen an-notation set is sufficient to define a game that is a plausibly acceptable rep-resentation of the text.
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- Date Issued: 2010
Minimum spanning trees for valley and ridge characterization in digital elevation maps
- Authors: Bangay, Shaun D , de Bruyn, David , Glass, Kevin R
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433247 , vital:72955 , https://doi.org/10.1145/1811158.1811171
- Description: Texture synthesis employs neighbourhood matching to generate appropriate new content. Terrain synthesis has the added constraint that new content must be geographically plausible. The profile recognition and polygon breaking algorithm (PPA) [Chang et al. 1998] provides a robust mechanism for characterizing terrain as systems of valley and ridge lines in digital elevation maps. We exploit this to create a terrain characterization metric that is robust, efficient to compute and is sensitive to terrain properties.
- Full Text:
- Date Issued: 2010
Parallel packet classification using GPU co-processors
- Authors: Nottingham, Alistair , Irwin, Barry V W
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430250 , vital:72677 , https://doi.org/10.1145/1899503.1899529
- Description: In the domain of network security, packet filtering for classification pur-poses is of significant interest. Packet classification provides a mecha-nism for understanding the composition of packet streams arriving at distinct network interfaces, and is useful in diagnosing threats and un-covering vulnerabilities so as to maximise data integrity and system se-curity. Traditional packet classifiers, such as PCAP, have utilised Con-trol Flow Graphs (CFGs) in representing filter sets, due to both their amenability to optimisation, and their inherent structural applicability to the metaphor of decision-based classification. Unfortunately, CFGs do not map well to cooperative processing implementations, and single-threaded CPU-based implementations have proven too slow for real-time classification against multiple arbitrary filters on next generation networks. In this paper, we consider a novel multithreaded classification algorithm, optimised for execution on GPU co-processors, intended to accelerate classification throughput and maximise processing efficien-cy in a highly parallel execution context.
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- Date Issued: 2010