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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.
1

QoS in MPLS and IP Networks / QoS in MPLS and IP Networks

Sabri, Gull Hussain January 2009 (has links)
The thesis report provides broader information about IP and MPLS technologies and routing protocols. Internet architecture and problems in an IP networks are illustrated when different internet protocols are used. Small focus is provides on the demand oriented real time applications and data traffic for QoS parameters in IP and MPLS networks. Evaluation of QoS guarantee parameters such as delay, jitter and throughput are described with state of art study results mainly for real time applications in IP and MPLS networks. Finally MPLS TE implementation and working is described and proposed to achieve better network performance.
2

On the Design of Next-Generation Routers and IP Networks

Fu, Jing January 2008 (has links)
This thesis investigates distributed router architectures and IP networks with centralized control. While the current trend in IP-router architectures is towards decentralized design, there have also been research proposals for centralizing the control functions in IP networks. With continuous evolution of routers and IP networks, we believe that eventually IP networks in an autonomous system (AS) and a distributed router might converge into one network system. This system, which can be considered both as a distributed router and a centrally-controlled IP network, is divided into a control plane and a forwarding plane. The control plane is responsible for routing, management and signalling protocols, while the forwarding plane is responsible for forwarding packets. The work in this thesis covers both the forwarding and control planes. In the forwarding plane, we study network processor systems that function as forwarding elements in a distributed router. We introduce a system model and a simulation tool based on the model. Using the simulation tool, we investigate network processor system design by studying throughput, utilization, queueing behavior and packet delays. In addition to network processor systems, we study IP-address lookup, which is one of the key packet processing functions in Internet routers. Our work in IP-address lookup contains an efficient lookup algorithm, a scheme to divide the lookup procedure into two-stages in a distributed router, and an approach to perform efficient lookup on a router supporting multiple virtual routers. In the control plane, we study three emerging research issues with centralized control. We provide a thorough study of the routing convergence process in networks with centralized control, and compare it with decentralized link-state routing protocols. We propose an efficient approach to perform traffic engineering and routing in networks with centralized control, and compare it with an approach using optimized link weights. Finally, we present an approach to perform loop-free updates of forwarding tables when the forwarding paths change. This loop-free update approach is particularly useful in networks with centralized control. The results presented in this thesis are useful for building next-generation routers and IP networks with centralized control that might eventually converge into one network system. / QC 20100726
3

Green IPTV : a resource and energy efficient network for IPTV

Valente Ramos, Fernando Manuel January 2013 (has links)
The distribution of television is currently dominated by three technologies: over-the-air broadcast, cable, and satellite. The advent of IP networks and the increased availability of broadband access created a new vehicle for the distribution of TV services. The distribution of digital TV services over IP networks, or IPTV, offers carriers flexibility and added value in the form of additional services. It causes therefore no surprise the rapid roll-out of IPTV services by operators worldwide in the past few years. IPTV distribution imposes stringent requirements on both performance and reliability. It is therefore challenging for an IPTV operator to guarantee the quality of experience expected by its users, and doing so in an efficient manner. In this dissertation I investigate some of the challenges faced by IPTV distribution network operators, and I propose novel techniques to address these challenges. First, I address one of the major concerns of IPTV network deployment: channel change delay. This is the latency experienced by users when switching between TV channels. Synchronisation and buffering of video streams can cause channel change delays of several seconds. I perform an empirical analysis of a particular solution to the channel change delay problem, namely, predictive pre-joining of TV channels. In this scheme each Set Top Box simultaneously joins additional multicast groups (TV channels) along with the one requested by the user. If the user switches to any of these channels next, switching latency is virtually eliminated, and user experience is improved. The results show that it is possible to eliminate zapping delay for a significant percentage of channel switching requests with little impact in access network bandwidth cost. Second, I propose a technique to increase the resource and energy efficiency of IPTV networks. This technique is based on a simple paradigm: avoiding waste. To reduce the inefficiencies of current static multicast distribution schemes, I propose a semi-dynamic scheme where only a selection of TV multicast groups is distributed in the network, instead of all. I perform an empirical evaluation of this method and conclude that its use results in significant bandwidth reductions without compromising service performance. I also demonstrate that these reductions may translate into significant energy savings in the future. Third, to increase energy efficiency further I propose a novel energy and resource friendly protocol for core optical IPTV networks. The idea is for popular IPTV traffic to optically bypass the network nodes, avoiding electronic processing. I evaluate this proposal empirically and conclude that the introduction of optical switching techniques results in a significant increase in the energy efficiency of IPTV networks. All the schemes I present in this dissertation are evaluated by means of trace-driven analyses using a dataset from an operational IPTV service provider. Such thorough and realistic evaluation enables the assessment of the proposed techniques with an increased level of confidence, and is therefore a strength of this dissertation.
4

SIGTRAN : Signaling over IP -- a step closer to an all-IP network

Immonen, Mia January 2005 (has links)
The mass popularization of telecommunication services in recent years have resulted in a heavily loaded signaling network. The Signaling System number 7 (SS7) is used in fixed and wireless networks and is needed for call control and services such as caller ID, roaming, and for sending SMS. The traditional SS7 networks are expensive to lease and to expand, hence a new suite of protocols have been designed to carry signaling messages over IP. This suite contains a transport protocol called Stream Control Transmission Protocol (SCTP) and various user adaptation layer protocols such as M2PA, M2UA, M3UA, and SUA. To transport the highly loss and delay sensitive signaling messages over IP, it is mandatory that the transport protocol meets the high performance requirements of SS7. Not before the IP-solution has been tested in detail, will it replace significant parts of the national telephone network. In this thesis, the failover duration in the case of link failure was tested using the feature of SCTP called multi-homing. The results suggest that carrying SS7 signaling traffic over IP is possible, since the failover duration does not exceed the required limit. / Under de senaste åren har telekommunikationstjänster blivit allt mer populära, vilket har lett till ett tungt belastat signaleringsnätverk. The Signaling System number 7 (SS7) används i fasta och trådlösa nätverk och behövs för att kontrollera telefonsamtal och för tjänster såsom caller ID, roaming och för att skicka SMS. De traditionella SS7- nätverken är dyra att hyra och att expandera, varför en ny grupp av protokoll har designats för att bära signaleringsmeddelanden över IP. De nya protokollen innehåller ett transportprotokoll som heter Stream Transmission Control Protocol (SCTP) och flera adaptionslagerprotokoll, bl.a. M2PA, M2UA, M3UA och SUA. För att transportera de förlust- och förseningskänsliga signaleringsmeddelandena över IP, måste transportprotokollet möta de höga krav som SS7 har. Inte förrän IP-lösningen har testats ingående, kommer den att ersätta betydelsefulla delar av det nationella telefonnätet. I detta examensarbete har failovertiden mätts då en nätverkslänk mellan två noder har utsatts för ett avbrott. Resultaten pekar på att det är möjligt att bära SS7-trafik över IP eftersom failovertidskraven inte överstigs.
5

A NOVEL SCHEME TO PROVIDE MULTICAST OVER MOBILE-IP

GOSSAIN, HRISHIKESH 17 April 2003 (has links)
No description available.
6

Routing of traffic in an IP-network using combined routing patterns

Lindblad, Andreas January 2015 (has links)
In IP networks using the OPSF-principle together with the ECMP-principle, thetraffic is routed in all shortest paths. Weights on links are set by an administrator,not knowing how the resulting routing pattern will become. In this final thesis, I givea heuristic solution to the problem of changing a set of desired routing patterns inan ordered way to make them compatible with each other. An implementation of thealgorithm has been made and some testing with provided data for performance is alsopresented.
7

Design of an autonomic system for IP-network environments

Ljungdahl, Emil, Andersson, Erik January 2009 (has links)
<p>A2B Electronics AB is a company that develops and manufactures products and technology for digital cable television. A2B's new EXM-product family translates digital television channels from multiple source networks into a single destination network. Multiple EXM-units are connected in a system to provide a custom set of TV channels. To minimize the administrative effort, the units in a system should be able to interact and collaborate without manual intervention. The purpose of this thesis is to propose an underlying system that supports seamless interaction and collaboration between units.</p><p>The autonomic system concept has served as a foundation for the proposed solution. The requirements for the EXM-system proved to be similar to many properties of an autonomic system. The proposed solution was elaborated by answering five reseach questions. The answers describe how an autonomic system can be implemented with the prerequisites of the EXM-system. Solutions for service availability, configuration preservation, system state changes and automatic addressing and communication are provided.</p><p>The project has resulted in a proposal of a general autonomic system. The solution has also been implemented as prototype that runs both in a simulator and on the EXM-hardware. The simulator was also developed in the scope of this project as a side-effect of the limited access to EXM-hardware.</p><p>The proposed solution together with the prototype can hopefully serve as a base for projects with prerequisites similar to the project described in this thesis.</p>
8

Multipath TCP and Measuring end-to-end TCP Throughput : Multipath TCP Descriptions and Ways to Improve TCP Performance

BONAM, VEERA VENKATA SIVARAMAKRISHNA January 2018 (has links)
Internet applications make use of the services provided by a transport protocol, such as TCP (a reliable, in-order stream protocol). We use this term Transport Service to mean the end-to- end service provided to application by the transport layer.   That service can only be provided correctly if information about the intended usage is supplied from the application. The application may determine this information at the design time, compile time, or run time, and it may include guidance on whether a feature is required, a preference by the application, or something in between. Multipath TCP (MPTCP) adds the capability of using multiple paths to a regular TCP session. Even though it is designed to be totally backward compatible to applications. The data transport differs compared to regular TCP, and there are several additional degrees of freedom that the particular application may want to exploit.   Multipath TCP is particularly useful in the context of wireless networks using both Wi-Fi and a mobile network is a typical use case. In addition to the gains in throughput from inverse multiplexing, links may be added or dropped as the user moves in or out of coverage without disrupting the end-to-end TCP connection. The problem of link handover is thus solved by abstraction in the transport layer, without any special mechanisms at the network or link level.   Handover functionality can then be implemented at the endpoints without requiring special functionality in the sub-networks according to the Internet's end-to-end principle. Multipath TCP can balance a single TCP connection across multiple interfaces and reach very high throughput.
9

Multipath TCP and Measuring endto-end TCP Throughput : Measuring TCP Metrics and ways to improve TCP Throughput performance

SANA, VINEESHA January 2018 (has links)
Internet applications make use of the services provided by a transport protocol, such as TCP (a reliable, in-order stream protocol). We use the term Transport Service to mean the endtoend service provided to application by the transport layer. That service can only be provided correctly if information about the intended usage is supplied from the application. The application may determine this information at the design time, compile time, or run time, and it may include guidance on whether a feature is required, a preference by the application, or something in between. Multipath TCP (MPTCP) adds the capability of using multiple paths to a regular TCP session. Even though it is designed to be totally backward compatible to applications. The data transport differs compared to regular TCP, and there are several additional degrees of freedom that the particular application may want to exploit. Multipath TCP is particularly useful in the context of wireless networks using both Wi-Fi and a mobile network is a typical use case. In addition to the gains in throughput from inverse multiplexing, links may be added or dropped as the user moves in or out of coverage without disrupting the end-to-end TCP connection. The problem of link handover is thus solved by abstraction in the transport layer, without any special mechanisms at the network or link level. Handover functionality can then be implemented at the endpoints without requiring special functionality in the sub-networks according to the Internet's end-to-end principle. Multipath TCP can balance a single TCP connection across multiple interfaces and reach very high throughput.
10

Design of an autonomic system for IP-network environments

Ljungdahl, Emil, Andersson, Erik January 2009 (has links)
A2B Electronics AB is a company that develops and manufactures products and technology for digital cable television. A2B's new EXM-product family translates digital television channels from multiple source networks into a single destination network. Multiple EXM-units are connected in a system to provide a custom set of TV channels. To minimize the administrative effort, the units in a system should be able to interact and collaborate without manual intervention. The purpose of this thesis is to propose an underlying system that supports seamless interaction and collaboration between units. The autonomic system concept has served as a foundation for the proposed solution. The requirements for the EXM-system proved to be similar to many properties of an autonomic system. The proposed solution was elaborated by answering five reseach questions. The answers describe how an autonomic system can be implemented with the prerequisites of the EXM-system. Solutions for service availability, configuration preservation, system state changes and automatic addressing and communication are provided. The project has resulted in a proposal of a general autonomic system. The solution has also been implemented as prototype that runs both in a simulator and on the EXM-hardware. The simulator was also developed in the scope of this project as a side-effect of the limited access to EXM-hardware. The proposed solution together with the prototype can hopefully serve as a base for projects with prerequisites similar to the project described in this thesis.

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