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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Application of IP Multicasting to the NASA Communications Command and Telemetry Ground Network

Spinolo, M. Chris 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / The NASA Communications (Nascom) Division has been directed to deploy Internet Protocol (IP) based technology for the ground segments of all present and future spaceflight telemetry networks. The Nascom network supports all NASA spaceflight telemetry, command and status requirements, from sounding rockets and balloons to the Hubble Space Telescope and the Space Shuttle. This paper discusses the challenges of transitioning a 35 year old, custom engineered, worldwide legacy telemetry network to IP, and the resulting, new NASA IP Operational Network for ground transport of spacecraft telemetry and command.
12

Performance of Voice-over-IP over iNET Telemetric Networks

Moodie, Myron L., Newton, Todd A., Grace, Thomas B., Malatesta, William A. 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Bidirectional networked radio frequency (RF) communications between the ground and test articles are quickly becoming a normal mode of operation. Not only can devices be remotely controlled, but other networking technologies are emerging into flight test. Voice over IP (VoIP) is ubiquitous in the workplace and in homes, but it presents unique challenges when used to communicate between test articles. This paper presents some issues to be considered and test results to help aid deployment of VoIP systems in network-based test systems such as iNET's Telemetry Network System (TmNS).
13

DoS a DDoS útoky na SIP protokol / DoS a DDoS útoky na SIP protokol

Staněk, Jan January 2011 (has links)
The aim of this diploma thesis is to get accustomed with the SIP protocol and with the problematics of attacks targeting this protocol, with the emphasis on DoS and DDoS attacks. The thesis focuses on detailed classification of the attacks, possibilities and forms of generation of the attacks and methodics of defense against them. The attacks of the flood type are especially stressed because they are easily generated and the SIP components are very prone to these attacks. Prototype implementations of the most important ideas concerning attack generation and protection against these attacks are also part of this thesis. Practical tests of the implementations performed in a simulated SIP environment are also included. 1
14

Uma aplicação de voz sobre IP baseada no Session Initiation Protocol

Maia da Silva Junior, Jucimar January 2006 (has links)
Made available in DSpace on 2014-06-12T17:40:34Z (GMT). No. of bitstreams: 2 arquivo7027_1.pdf: 1272687 bytes, checksum: c206e6550646b7fa69162772329c811f (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / Neste trabalho é implementada uma aplicação de Voz Sobre IP utilizando o Session Initiation Protocol (SIP) como protocolo de sinalização. Para alcançar este objetivo, são analisadas algumas tecnologias importantes, como os protocolos da Internet Engineering Task Force (IETF) para Telefonia IP, codificadores de voz, e a utilização da aplicação para verificação de atrasos, jitter e perda de pacotes. A aplicação foi desenvolvida em Java e pode facilmente ser modificada para adequar novos codificadores de voz e características mais recentes que novas especificações do SIP possam implementar
15

Explicit congestion control algorithms for time-varying capacity media

Abrantes, Filipe Lameiro January 2008 (has links)
Tese de doutoramento. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 2008
16

Odhad geografické polohy stanic v Internetu / Location estimation of Internet nodes

Němeček, Ladislav January 2014 (has links)
This paper deals with methods of stations’ IP geolocation. It’s describes the methods of passive and active geolocation and it’s more focused on active searching methods, which usees measuring the latency in network. The factors causing delays in data transfer are discussed first, followed by discussion of the issue of measuring these delays. After that a brief description of PlanetLab experimental network, which nodes were used for delay measurment. Main topic is practical implementation of method Constraint-based Geolocation in Java programming language. Last but not least the measurement results of CBG algorithm are tested.
17

IP Telephony : A Swedish Perspective

Sjöstedt, Magnus, Bergquist, Oskar January 2003 (has links)
The aim of this Masters Thesis project is to give the Swedish National Post and Telecom Agency, Post- och Telestyrelsen (PTS), an updated view on I P Telephony relative to the Swedish consumer market. The basic questions were raised by PTS and the focus is on the relevant topics from the agency’s point of view. PTS is primarily interested in understanding what state IP Telephony is in and furthermore what IP Telephony can be used for in practice. What are the possibilities of different implementations and what will be their advantages and disadvantages? Despite being on the scene for many years, IP Telephony is now on the verge of a break through. With the creation of gateways between IP and PSTN, various IP Telephony devices, and with the introduction of SIP (described in RFC2543) as a standard signalling protocol, perhaps today, IP Telephony has a significant potential on the consumer market. Many argue that 2003 will be the year that IP Telephony blossoms. The fact that anyone can be their own operator, the role of the traditional operator versus the new operators, the separation of content and signalling transmission, as well as the efficient use of bandwidth are some of the topics covered in this report.</p> Due to the introduction of The Electronic Communications Act that comes into effect the 25th of July 2003, replacing The Telecommunications Act and The Radiocommunications Act, much of the focus in this report lies on regulatory issues. However, in order to get an insight in to the regulatory issues it is important to understand the underlying technology of IP Telephony as well as areas such as security, robustness, privacy, and emergency calls. Through a market analysis, an updated overview of the market for IP Telephony will be given, along with plausible future scenarios. This report will provide the reader with answers not by focusing on the theoretical details of the technology itself, but rather in terms of it’s practical use and limitations. / Syftet med denna rapport är att ge Post- och Telestyrelsen (PTS) en uppdaterad bild av den svenska IP-telefonimarknaden för privatpersoner. Då examensarbetet utfördes för PTS togs de grundläggande frågeställningarna fram av myndigheten och fokus för examensarbetet lades således på ämnen relevanta för PTS. Trots att IP-telefoni har varit på tapeten i flera år, har tekniken ännu inte haft sitt genombrott på privatmarknaden. Existensen av slussar mellan IP och PSTN, samt utvecklingen av IP-telefoniutrustning och standardiserade protokoll (såsom SIP beskriven i RFC2543), har givit IP-telefoni förutsättningen att ta en signifikant roll på den svenska privatmarknaden. Många anser att 2003 är året då IP-telefoni kommer att ha sitt genombrott. Utvecklingen och ändringen av den traditionella operatörsrollen, separationen av signaltrafik och samtalstrafik samt den effektiva och variabla användningen av bandbredd, är några av de faktorer som ger upphov till spännande frågeställningar. Introduktionen av lagen för elektronisk kommunikation som träder i kraft den 25 Juli 2003, och ersätter både telelagen och lagen om radiokommunikation, har gjort att fokus till stor del riktas på de regulativa frågorna inom området. För att sätta sig in i dessa regulativa frågor krävs dock god insikt i tekniken bakom IP-telefoni samt förståelse i områden såsom säkerhet, robusthet, QoS och nödsamtal. En marknadsanalys bidrar med en uppdaterad bild av marknaden för IP-telefoni samt möjliga framtidscenarion. Rapporten förser läsaren med svar genom att fokusera på teknikens praktiska användning och begränsningar snarare än att fokusera på de teoretiska detaljerna.
18

Data, Information, and Knowledge Management

Harley, Samuel, Reil, Michael, Blunt-Henderson, Thea, Bartlett, George 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Aberdeen Test Center Versatile Information System – Integrated, ONline (VISION) project has developed and deployed a telemetry capability based upon modular instrumentation, seamless communications, and the VISION Digital Library. Each of the three key elements of VISION contributes to a holistic solution to the data collection, distribution, and management requirements of Test and Evaluation. This paper provides an overview of VISION instrumentation, communications, and overall data management technologies, with a focus on engineering performance data.
19

Packet-Based Best Source Selector and Other IP-Telemetry Tricks

Newton, Todd A., Abbott, Ben A. 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / IP-telemetry radios are being connected to existing ground networks, thereby integrating the air and ground. While this provides full connection to Test Article (TA) networks, the mobility of TAs and the transient nature of test missions leave the overall experience feeling less than "real" networks. We describe a toolset that extends the capabilities of integrated IP-telemetry and range networks through specialized routing techniques focused on mission-based data delivery needs. The toolset provides a configurable capability enabling packet-based best source selection, firewalling, multicasting, and QoS enforcement across the range on a per program basis. The building blocks of the toolset allow for the creation of virtualized network components that are mission-based rather than infrastructure and enables seamless network operation with network telemetry, giving mission personnel the ability to specialize the network for their needs without depending upon the range IT department.
20

Accomplishing Seamless IP Mobility in iNET Systems

Moodie, Myron L., Araujo, Maria S., Newton, Todd A., Abbott, Ben A., Grace, Thomas B. 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / One of the core philosophies of the integrated Network Enhanced Telemetry (iNET) project is to leverage standard networking technologies whenever possible to both reduce development cost and to allow standard networking applications to function. This also provides the best long-term scalability to new unforeseen applications, much as the Internet has grown through its open standards. Unfortunately, the radio frequency (RF) channel characteristics do not fully lend themselves to the typical physical layer approaches utilized by IP technologies. As such, the iNET program has developed a specialized communication link management control. But, combining this specialized link management approach with the standardized IP infrastructure on the range and test article provides some challenges. The program has chosen a method to encapsulate the special concepts within a set of components that together (at their boundaries) form a classic router. Construction of this router is quite unique in that portions of it are geographically separate: antenna sites, test article, and mission control room. This paper describes the construction of what the program calls a "virtual router" and explains the performance issues that required it.

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