Please read the abstract in the section 00front of this document / Dissertation (MSc (Computer Science))--University of Pretoria, 2006. / Computer Science / unrestricted

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Överföring eller mottagande av datorfiler är en syssla som de flesta av oss ägnar ossåt regelbundet i ett eller annat sammanhang, oavsett om det sker privat eller om detär arbetsrelaterat. File Transfer Protocol (FTP) är ett protokoll för just detta ändamålsom lanserades under tiden då persondatorer hade blivit allt vanligare i hemmetoch på arbetsplatsen. Sedan dess har flera andra protokoll introducerats och i dagslägetfinns det flertalet valmöjligheter tillgängliga, alla med sina unika såväl som gemensammaegenskaper. Simple Mail Transfer Protocol (SMTP) kompletterad medMIME-standarden är ett populärt alternativ till de renodlade filöverföringsprotokollenpå grund av användarnas bekantskap och tidigare erfarenheter med e-posttjänster.Att skicka och ta emot filer via e-post innebär dock vissa begränsningar samt att vissasäkerhetsaspekter måste tas i beaktande, i synnerhet för företagsanvändare som dagin och dag ut måste hantera känslig data. I denna uppsats har tre olika filöverföringsprotokoll(SFTP, SMTP och HTTP) utvärderats ur ett användarvänlighetsperspektivsåväl som ett säkerhetsperspektiv. Resultatet indikerar att HTTP(S) tillsammans meduttökningen WebDAV kan anses vara ett lämpligt alternativ för organisationer somsamtidigt är enkelt att använda. De övriga protokollen, SMTP och SFTP, har ocksåsina användningsområden där SFTP verkar vara mer tilltalande för avanceradeanvändare och där SMTP förblir ett gångbart alternativ för privat bruk av mindreavancerade användare under vissa förutsättningar. / Transferring and receiving computer files are something most of us do on a regularbasis whether it is for private purposes or if it is work related. FTP is a protocolused for this very purpose which was launched during a time when personal computerswere growing increasingly popular in both home and workplace environments.Since then, more protocols have been introduced and today there are a number ofoptions available bringing new and common features alike to the market. The SMTPprotocol, extended with the MIME standard, is currently a widely used alternative tothe pure file transfer protocols due to the user familiarity and past experiences withthese mail services. Sending and receiving files through e-mail does however implysome limitations together with the fact that some security aspects need to be takeninto consideration, particularly for company users handling sensitive data. In thisthesis, three different file transfer protocols (SMTP, SFTP and HTTP) have all beenevaluated in account of their user friendliness as well as their security features. Theresults indicate that HTTP(S) combined with the WebDAV extension can be considereda viable alternative for organizations due to its user friendliness and security.The remaining protocols, SMTP and SFTP, also have their uses where SFTP wouldseem to be an appealing option for advanced users and where SMTP remains a passablealternative for private usage by regular users under the right conditions.

This thesis deals with theoretical analysis of First Hop Redundancy Protocols. It describes Hot Standby Router Protocol, Virtual Router Redundancy Protocol and Gateway Load Balancing Protocol. It also shows examples of configuration of each protocol on Cisco devices with supported version of the Cisco IOS. Furthermore, this thesis includes design of two of these protocols, Hot Standby Router Protocol and Gateway Load Balancing Protocol, and their implementation in discrete event simulator OMNeT++ and Automated Network Simulation and Analysis library. Finally, the thesis presents results of testing of the implementations in comparison with actual Cisco devices.

ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The integrated Network-Enhanced Telemetry (iNET) Test Article Standards Working Group (TASWG) has developed a standard for Telemetry Network System (TmNS). The introduction of Internet Protocol (IP) networks on test ranges has created the potential for greater flexibility in the telemetry environment. This paper discusses the rationale for particular decisions concerning key components mandated by the standard. Performance implications concerning the mandates of the standard are also described. As an educational aid, examples of TAS-based processing philosophies and data structures have been constructed. These examples, including sending and receiving messages, are shown to reinforce understanding core concepts of the standard.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The RCC TTG initiated task TT-49 to generate a standard for the transport of serial streaming telemetry (TM) over the Internet Protocol (IP). An ad hoc committee was activated comprised of Range and vendor participation to develop this standard. This paper will address the progress of the standard, the use of commercial standards, and the benefits to the ranges. The early meetings focused on developing the packet structure; the preliminary results will be presented along with the latest status on the RCC approval cycle.

OBJECTIVE: We aimed to evaluate whether early administration of high plasma to red blood cells ratios influences outcomes in injured patients who received massive transfusion protocol (MTP). METHODS: A retrospective analysis was conducted at the only level 1 national trauma center in Qatar for all adult patients(≥18 years old) who received MTP (≥10 units) of packed red blood cell (PRBC) during the initial 24 h post traumatic injury. Data were analyzed with respect to FFB:PRBC ratio [(high ≥ 1:1.5) (HMTP) vs. (low < 1:1.5) (LMTP)] given at the first 4 h post-injury and also between (>4 and 24 h). Mortality, multiorgan failure (MOF) and infectious complications were studied as well. RESULTS: During the study period, a total of 4864 trauma patients were admitted to the hospital, 1.6 % (n = 77) of them met the inclusion criteria. Both groups were comparable with respect to initial pH, international normalized ratio, injury severity score, revised trauma score and development of infectious complications. However, HMTP was associated with lower crude mortality (41.9 vs. 78.3 %, p = 0.001) and lower rate of MOF (48.4 vs. 87.0 %, p = 0.001). The number of deaths was 3 times higher in LMTP in comparison to HMTP within the first 30 days (36 vs. 13 cases). The majority of deaths occurred within the first 24 h (80.5 % in LMTP and 69 % in HMTP) and particularly within the first 6 h (55 vs. 46 %). CONCLUSIONS: Aggressive attainment of high FFP/PRBC ratios as early as 4 h post-injury can substantially improve outcomes in trauma patients.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A novel satellite multiple access scheme called PR-CFDAMA (Predictive Request-Combined Free/Demand Assignment Multiple Access) is proposed in this paper. The delay performances between PR-CFDAMA and R-CFDAMA (Round Robin-CFDAMA) scheme were compared by computer simulation. Simulations were carried out with the Interrupted Poisson Process (IPP) and Interrupted Fluid Process (IFP) traffic models. Simulation results demonstrate that comparing with R-CFDAMA scheme, the PR-CFDAMA scheme achieves a lower delay, meets a much lower delay constraint.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The CCSDS recently developed the CCSDS File Delivery Protocol which can operate in configurations from simple point-to-point space/ground systems to complex arrangements of orbiters, landers, relaying spacecraft, and multiple ground facilities. An international interoperability test program has been developed in support of the development and fielding of the protocol. The first phase was successfully completed in the Fall of 2002. The second phase is to be completed about the time of the presentation of this paper. First phase testing involved five independent implementations of the Core Procedures of the protocol. Since these Procedures are for point-to-point file transfers, only two protocol “entities” were involved in each executed test. The second phase tests other Procedures, which involve multi-hop transferring of files. This phase will involve two separate, independent implementations, with one implementation being hosted on multiple hardware/OS platforms. Each test will involve three or more entities.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / The role of recorders in telemetry applications has undergone many changes throughout the years. We’ve seen the evolution from multi-track tape to disk to solid state technologies, both for airborne and ground based equipment. Data acquisition and collection system design has changed as well and a recent trend in airborne is to merge acquisition and recording. On the ground, increased decentralization of data collection and processing has generated the requirement to provide backup storage to protect against communication circuit outages. This paper explores the trend to adopt network based data acquisition, collection, and distribution systems for telemetry applications and the impact on recording techniques and equipment. It shows that in this emerging approach the recorder returns to its root mission of attempting to provide the fastest, largest capacity for the least amount of investment. In a network based architecture the recorder need only accept and reproduce data operating independently from the acquisition process.