Dissertations / Theses on the topic 'ISDN'
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1
Liu, Zhengyu. "Interconnection of LANs through ISDN." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/11024.
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Network interconnection (internetworking) is an important issue in the area of computer communication. One of the purposes of internetworking is to allow communication to go beyond a single local area network (LAN). In this thesis, networks interconnection is studied. An internetworking device - (gate-way) is proposed to provide the capability of internetwork data transmission between LANs through an ISDN (Integrated Service Digital Network). This gateway is an application layer program which interfaces with the NetBIOS (Network Input Output System), a widely implemented interface between application programs and LANs in the IBM personal computer world. The NetBIOS interface is provided in both LAN and ISDN environments in a connection-oriented mode. A facility for file transfer and information exchange among LANs through ISDN is developed in such a way that it neither affects the existing network hardware and software available in both LANs and ISDN nor changes the mechanism of communication within a LAN. In particular, the emphasis is given to the specification, design and implementation of the gateway. In our model, the gateway is specified with a finite state machine. Based on the model, the gateway is designed by considering the issues of naming, name assigning, buffering, session handling, multi-session managing and error processing. A prototype of the gateway is implemented on a PC/XT computer with a LAN adapter, an ISDN adapter and the gateway program coded in "C". Performance benchmarks are conducted in terms of two factors: Message size and background traffic. These factors may affect the performance of internetwork data transmission. Finally, test results on different network conditions are given.
2
Wang, Lei. "Bandwidth contracting in B-ISDN." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ32801.pdf.
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Tan, Zhijie. "The broadband ISDN source simulator /." Title page, abstract and contents only, 1991. http://web4.library.adelaide.edu.au/theses/09ENS/09enst1612.pdf.
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Wong, Timothy Tin-Cho. "A multi-LAN/ISDN bridge." Thesis, University of Manchester, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386881.
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Lafrenière, Luc. "Parameter negotiation in a B-ISDN environment." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq22771.pdf.
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Newton, Christopher A. "An ISDN environment for the NeXT machine." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/8229.
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Sailer, Reiner. "Sicherheitsarchitektur für mehrseitig sichere Kommunikationsdienste am Beispiel ISDN /." Stuttgart : Inst. für Nachrichtenvermittlung und Datenverarbeitung, 1999. http://www.gbv.de/dms/bs/toc/311389791.pdf.
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Fróes, Lima Carlos Alberto 1963. "Analise de OAM para equipamentos da B-ISDN." [s.n.], 1995. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259774.
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Orientador: Rege Romeu ScarabucciDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica
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Resumo: A evolução das redes digitais e de uma nova tecnologia de comutação e multiplexação em altas taxas - ATM(Asynchronous Transfer Mode) ¿ garantiu uma forma flexível para a interligaçãoem rede. Da padronização do ITU-T e de diversos foros de fabricantes, aliando a indústria da informática com a indústria de telecomunicações pretende-se uma universalidade no processo de transferência de informações nas próximas décadas. Dentro desta característica de técnica integradora da tecnologia ATM, os equipamentos projetados deverão considerar, além do transporte propriamente da informação, a sua integração do ponto de vista de gerenciamento. Neste sentido, mecanismos de Operação, Administração, Manutenção e Provisionamento deverão estar contidos e padronizados nestes equipamentos. Este trabalho analisa as necessidades básicas de um equipamento que possa ser inserido na futura rede faixa larga de serviços integrados do ponto de vista de concepção de gerenciamento. Como exemplo da estrutura apresentada é também proposto um modelo para a Camada de protocolo ATMque contempla e exemplifica as funcionalidades requeridas em operação e gerenciamento de rede. Utilizando a linguagem formal de descrição e especificação SDL (Specification and Description Language) e diagramas de fluxo de mensagens MSC (Message Sequence Chart) a consistência deste modelo é verificada
Mestrado
Eletrônica, Microeletrônica e Optoeletrônica
Mestre em Engenharia Elétrica
9
Smith, Avril Joy. "A congestion control protocol for ATM cell switches." Thesis, Oxford Brookes University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261271.
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Harita, Bhaskar Ramanathan. "Dynamic bandwidth management." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385403.
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Mihlon, Lauren R. "Internetworking extending Local-Area Network (LAN) connectivity using ISDN /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA320736.
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Thesis (M.S. in Information Technology Management) Naval Postgraduate School, September 1996."September 1996." Thesis advisor(s): D.P. Brutzman, R. Buddenberg. Includes bibliographical references (p. 119-122). Also Available online.
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Pitsillides, Andreas, and Andreas Pitsillides@ucy ac cy. "Control structures and techniques for broadband-ISDN communication systems." Swinburne University of Technology, 1993. http://adt.lib.swin.edu.au./public/adt-VSWT20060321.132650.
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A structured organisation of tasks, possibly hierarchical, is necessary in a BISDN network due to the complexity of the system, its large dimension and its physical distribution in space. Feedback (possibly supplemented by feedforward) control has an essential role in the effective and efficient control of BISDN. Additionally, due to the nonstationarity of the network and its complexity, a number of different (dynamic) modelling techniques are required at each level of the hierarchy. Also, to increase the efficiency of the network and allow flexibility in the control actions (by extending the control horizon) the (dynamic) tradeoff between service-rate, buffer-space, cell-delay and cell-loss must be exploited. In this thesis we take account of the above and solve three essential control problems, required for the effective control of BISDN. These solutions are suitable for both stationary and nonstationary conditions. Also, they are suitable for implementation in a decentralised coordinated form, that can form a part of a hierarchical organisation of control tasks. Thus, the control schemes aim for global solutions, yet they are not limited by the propagation delay, which can be high in comparison to the dynamics of the controlled events.
Specifically, novel control approaches to the problems of Connection Admission Control (CAC), flow control and service-rate control are developed. We make use of adaptive feedback and adaptive feedforward control methodologies to solve the combined CAC and flow control problem. Using a novel control concept, based on only two groups of traffic (the controllable and uncontrollable group) we formulate a problem aimed at high (unity) utilisation of resources while maintaining quality of service at prescribed levels. Using certain assumptions we have proven that in the long term the regulator is stable and that it converges to zero regulation error. Bounds on operating conditions are also derived, and using simulation we show that high utilisation can be achieved as suggested by the theory, together with robustness for unforeseen traffic connections and disconnections. Even with such a high efficiency and strong properties on the quality of service provided, the only traffic descriptor required from the user is that of the peak rate of the uncontrollable traffic.
A novel scheme for the dynamic control of service-rate is formulated, using feedback from the network queues. We use a unified dynamic fluid flow equation to describe the virtual path (VP) and hence formulate two illustrative examples for the control of service-rate (at the VP level). One is a nonlinear optimal multilevel implementation, that features a coordinated decentralised solution. The other is a single level implementation that turns out to be computationally complex. Therefore, for the single level implementation the costate equilibrium solution is also derived. For the optimal policies derived, we discuss their implementation complexity and provide implementable solutions. Their performance is evaluated using simulation. Additionally, using an ad hoc approach we have extended previous published works on the decentralised coordinated control of large scale nonlinear systems to also deal with time-delayed systems.
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Johnny, Wong. "Performance evaluation of d-channel access protocols in ISDN." Thesis, The University of Sydney, 1986. https://hdl.handle.net/2123/28529.
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Chapter One introduces the concept of Integrated Services Digital Networks (ISDN).
A brief outline of the integration of voice and data services is given, indicating the different
characteristics of these two services. Evolution from the existing telephone networks towards
the full ISDN is mentioned, emphasizing the transition from analog to all digital in the
transmission facilities. The ISDN emphasizing and customer access are discussed together with
the access protocol architecture.
Chapter Two surveys the modelling and evaluation techniques in the study of communication
and computer systems. These include the analytical, simulation and direct measurement
methods. Common approaches to model queueing systems are described, with particular
interest in the modelling of multiple classes priority queues. Event-oriented simulation methodology is presented, including techniques to establish the credibility of the simulation models.
Chapter Three describes the access protocols that are suitable for the ISDN. Queueing
and simulation models, based on the approaches mentioned in Chapter Two, are used in the
performance studies and numerical comparisons. In particular, the pre-emptive access procedures are suggested as alternatives to improve the signalling delay.
Chapter Four derives an appropriate queueing model for the analysis of the 95 percentile
of the s-delay in ISDN, from which the Laplace Transform of the s-delay is obtained.
Inversion of the Laplace Transform can only be obtained by using numerical methods. Comparison with simulation results is made to validate the queueing model.
Chapter Five presents a new access protocol based on the packet-switching technology.
Each station is assumed to generate messages consisting of an arbitrarily distributed, random
number of fixed size packets. The channel is time-slotted with a slot time equal to a packet
transmission time. The protocol ensures that an ongoing message transmission can not be preempted by any messages of the same class, but can be pre-empted at the beginning of the next slot by a higher priority message. Study of this protocol is based on simulation and analytical techniques. From the mean signalling delay formula derived, the optimal packet size is obtained. With the optimal packet size, the performance of the mean signalling delay of the
Packet Switching protocol is found to be as good as those preemptive ones. Comparisons
between various priority protocols are presented to indicate the delay-throughput characteristics among them.
Chapter Six discusses the fairness of the access protocols in ISDN. The fairness measure
is according to the average end-to-end message delay for each station. This issue is studied
through the design aspects of the scheduling disciplines. A Random Number Prefix scheme is
proposed to improve the fairness measure.
Chapter Seven summarises the major conclusions reached from the investigations.
Further researches are suggested and discussed.
14
Lin, Cheng-Leo George 1958. "Performance evaluation of interconnection networks for ISDN switching applications." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277322.
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Interconnection Networks of various designs have been proposed for use as fast packet switches for broadband ISDN applications. We use stochastic activity networks to model and simulate these designs. In particular, we use stochastic activity networks to compare three switch designs (basic banyan, modified delta, and a design with multiplexer and demultiplexer) under both uniform and non-uniform workload assumptions. Regarding contention resolution, we consider two policies, one with blocking, and one where the packet is rejected and must be retransmitted. For each scenario, we determine blocking probability and mean transmission delay. We find that while traditional designs work well with uniform workloads, they do not work so well with non-uniform workloads, and in fact, the simpler design with multiplexer and demultiplexer works better in some reject-retransmission cases. The modified delta network, due to its multiple path, performs the best among the three designs with uniform workloads. (Abstract shortened with permission of author.)
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Swedan, S. E. K. "Performance analysis of user access methods in the U.K. ISDN." Thesis, University of Strathclyde, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381142.
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Makhamreh, Ibrahim Issa. "Modeling and analysis of packet switch architectures for broadband ISDN." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/6928.
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In this thesis we analyze broadband switching architectures based on the Asynchronous Transfer Mode (ATM). Many architectures have been proposed in the literature for high-speed packet switches. We first review some of these switch architectures and their performance. The high-performance switch architectures, in general, require that the buffers be placed at the output ports. These output buffered switches tend to have large hardware complexity or require high speedup in their operation. Our focus is on high-performance switch architectures with low speedup output buffers or a shared buffer. An N $\times$ d ATM switch with finite output buffers is modeled as a discrete-time queue. The case d = 1 represents an ATM multiplexer with N input source and a finite capacity buffer. Loading at the input as well as at the output is considered to be imbalanced, which greatly affects the switch performance especially the hot spot traffic pattern. We also consider the switch with reduced speedup. In this case, the number of cells going to an output buffer in one time slot is limited to L N. This greatly simplifies the implementation of the switch. The arrivals to an input port of the switch, besides being bursty, are correlated in the sense that a burst arriving to an output port brings with it several cells belonging to the same virtual connection. As a worst case, we assume that consecutive cells in a burst are heading to the same output port. This greatly affects the dimensioning of the switch buffer. The input process to each input port is modeled by an Interrupted Bernoulli Process (IBP). We have developed an aggregation technique which allows the reduction of the state space that describes the arrival processes to the switch. This makes handling the output buffer driven by the induced process more manageable. Traffic priorities in ATM networks is an important issue because such networks will support applications with diverse traffic characteristics. In the light of this, we consider traffic priorities in an output buffered switch and in a completely shared-buffer switch. The transient analysis of the output buffer is also studied by considering the mean time until buffer overflow. The switch architecture that has the maximum mean-time-to-blocking is favorable. The busy period of the output buffer is also characterized. In routing the whole burst to an output buffer, the output process becomes more bursty than the input process.
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Gupta, Anil K. "Analysis of novel high-performance switch architectures for broadband-ISDN." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7888.
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In this thesis, we present an analysis of three novel switch architectures for Broadband-ISDN using the Asynchronous Transfer Mode (ATM). Our focus is on high-performance switch architectures, which have low to medium hardware complexity. The first switch architecture presented is a speed-up switch with input and output buffers, where a back-pressure mechanism is applied to avoid packet loss at the output buffers. We examine the maximum throughput, mean delay and packet loss rate at the input buffers of this speed-up switch. The switch with a speed-up of 3, and 20 buffers at each output port can achieve a maximum throughput of 90% or more. These results are of a great practical value since a switch with high speed-up is difficult to realize. A simple implementation of the switch is also presented. The second switch architecture, called Limited Intermediate Buffer (LIB) switch, is based on a crossbar switch fabric. A buffer to store a single packet is provided at each crosspoint of this switch. In addition to this, buffers are provided at the input ports to reduce the packet loss. We propose a new scheduling policy called head-of-line priority selection, which reduces the head-of-line blocking and thus improves the performance of the LIB switch substantially. A 16 x 16 switch under uniform random traffic can achieve a throughput of 87.5%. A three-stage interconnection network consisting of symmetric and asymmetric LIB switch modules is also presented. The simulation results of the interconnection network prove the efficacy of the LIB switch architecture and the proposed head-of-line priority selection scheme. Finally, the handling of delay and loss sensitive traffic in ATM networks is discussed. To keep the protocols simple at the ATM layer, we suggest that the handling of these priorities should be de-linked. The performance of two classes of delay-sensitive traffic in an input buffered nonblocking switch architecture is analyzed. The result of the analysis under two different non-preemptive priority schemes suggests that, to reduce the hardware complexity, the packets should not be distinguished based on their priority within the switch fabric. To overcome the throughput limitation of the input buffered switch, a dual plane switch architecture is presented, where each plane is a nonblocking switch with input buffers.
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Roohani, Siyer [Verfasser]. "Der Endothelinrezeptorantagonist Macitentan verbessert die Isosorbid-5-Mononitrat (ISMN) und Isosorbiddinitrat (ISDN)-induzierte endotheliale Dysfunktion, oxidativen Stress und vaskuläre Inflammation / Siyer Roohani." Mainz : Universitätsbibliothek der Johannes Gutenberg-Universität Mainz, 2021. http://d-nb.info/1224810570/34.
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Weerasiri, Don Kalana Manohara. "A synchronization technique to provide quality of service in broadband ISDN." Thesis, University of Canterbury. Electrical and Electronic Engineering, 1995. http://hdl.handle.net/10092/8902.
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This thesis analyzes the different Quality of Service (QoS) parameters that are important in setting up multimedia calls in Broadband ISDN (B-ISDN). Unlike in traditional telecommunication networks, service providers of Broadband ISDN provide guaranteed Quality of Service. This requires a comprehensive QoS management framework. The users of B-ISDN are able to adapt the Quality of Service of multimedia to their requirements. The main adaptable QoS parameters include video parameters, audio parameters and synchronization parameters. Intra-media synchronization and inter-media synchronization are important aspects of overall QoS provision. The audio and video streams of a particular source can be transmitted in different paths as these streams may have varying QoS requirements. Thus the audio and video streams will incur different transfer delays. The encoder and decoder processing delays of audio and video are also different. When presenting audio and video, the video stream should not be allowed to lag or lead the audio stream beyond acceptable skew tolerances. In specialized applications, multiple audio and video streams have to be played out in synchrony at the receiver. Also the layers of a layered coding system may be transmitted in different paths and the layers should be perfectly synchronized at the receiver.
Management of special resources such as layered encoders and decoders, media combiners code converters etc., ensures that intra-media and inter-media synchronization is maintained in isochronous communications. The different special resources and their relevance to QoS parameters such as intra-media and inter-media synchronization is discussed in detail.
In this thesis, a comprehensive synchronization mechanism called Static Delay
Compensation (SDC) is proposed to guarantee synchronization QoS. When synchronizing two or more media streams static delays are added to streams with lower end-to-end delays. It will be shown that SDC will satisfy almost all of the synchronization QoS requirements.
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Hamid, Khairuddin Ab. "Kalman prediction method for congestion avoidance in ISDN frame relaying networks." Thesis, University of Essex, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303473.
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Kapil, Vivek Carleton University Dissertation Engineering Electrical. "Measurement and characterisation of impulse noise on DSL for ISDN applications." Ottawa, 1989.
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Whitley, Toby. "Exploring mobility in wireless ATM networks." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367662.
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Salleh, Ahmad Zaki Mohd. "Transmission of time critical data over a packet satellite link." Thesis, University of Aberdeen, 1994. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU068949.
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This thesis presents some new techniques in frame oriented transmission systems with particular emphasis on HDLC (High Level Data Link Control) links. The advent of multimedia and applications requiring high bandwidth has prompted the development of high performance networks. In addition to that, accessibility is also an important issue. Satellite links have become a major contributor in providing access to larger networks where terrestrial connections are not possible due to geographical constraints. The development of VSATs (Very Small Aperture Terminal) has further increased the interest in providing extra-terrestrial links as a means of accessing a network. Because VSAT links are less reliable than terrestrial connections, bandwidth management becomes an important issue. The major problems are identified in this thesis. Frame oriented transmission systems have provided a very efficient method for data transmission. Data from several sources may be multiplexed into a common link. Recently, data networks have been successfully used for the transmission of various types of traffic. This diverse traffic has different QOS requirements such as throughput and delay. Certain types of traffic have an inherent priority. This traffic is referred to as time-critical or temporal. Temporal data has a short lifetime after which the data become useless regardless of whether the data has been corrupted or not. Some data sources such as voice and video, are able to tolerate small amounts of errors provided they are received within their lifetime period. From here we see that there are two very contrasting features of the data types. Conventional packet protocols are designed to ensure data integrity in return for packet delays due to retransmission and congestion control.
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Ip, W. H. "Cordless access to the basic rate service of ISDN using DECT technology." Thesis, Swansea University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637373.
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This thesis describes research that has been carried out by the author into the feasibility of providing a cordless (radio) access to the basic rate service of the integrated services digital network (ISDN). The radio technology investigated is based on that recently adopted as the pan-European cordless standard known as the Digital European Cordless Telecommunications (DECT) standard. Although in the standard it is envisaged that DECT will provide support for the basic service of ISDN, the actual interworking details between the two systems have still to be defined. This research, therefore, contributes to this aspect of the standard. The proposed scheme endeavours to merge the two systems together so as to provide transparent, cordless access to the basic rate service of ISDN. All aspects of the interworking approach have been fully researched and the operation of the interworking unit has been formulated in the form of a finite state machine. Most of the reported results for predicting the performance of a DECT radio link have been obtained using testbeds and relate to path loss, signal-to-noise ratio and fading characteristics. Although these parameters provide a good estimation of the performance of a link for voice services - in terms of bit error rate for example - in general, for the more stringent requirements of data services, the link performance of a channel, especially one of poor quality, dictates that an error correction scheme must be used. To date, however, the provision of data services over DECT has not yet been studied in detail. This research therefore also contributes to this aspect of the DECT standard. Two error correction schemes have been proposed and their performance under different channel conditions have been quantified. The results are based on error measurements obtained from a DECT testbed and computer simulation modelling has been used to investigate the performance of both schemes.
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Doble, James Carleton University Dissertation Engineering Electrical. "Distribution of protocol functions in an interworking-based ISDN switching node implementation." Ottawa, 1988.
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Omundsen, Daniel (Daniel Simon) Carleton University Dissertation Engineering Electrical. "A pipelined, multi-processor architecture for a connectionless server for broadband ISDN." Ottawa, 1992.
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Smith, Quentin D. "AN EVOLUTIONARY APPROACHTO A COMMUNICATIONS INFRASTRUCTURE FOR INTEGRATED VOICE, VIDEO AND HIGH SPEED DATA FROM RANGETO DESKTOP USING ATM." International Foundation for Telemetering, 1993. http://hdl.handle.net/10150/608864.
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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, NevadaAs technology progresses we are faced with ever increasing volumes and rates of raw and processed telemetry data along with digitized high resolution video and the less demanding areas of video conferencing, voice communications and general LAN-based data communications. The distribution of all this data has traditionally been accomplished by solutions designed to each particular data type. With the advent of Asynchronous Transfer Modes or ATM, a single technology now exists for providing an integrated solution to distributing these diverse data types. This allows an integrated set of switches, transmission equipment and fiber optics to provide multi-session connection speeds of 622 Megabits per second. ATM allows for the integration of many of the most widely used and emerging low, medium and high speed communications standards. These include SONET, FDDI, Broadband ISDN, Cell Relay, DS-3, Token Ring and Ethernet LANs. However, ATM is also very well suited to handle unique data formats and speeds, as is often the case with telemetry data. Additionally, ATM is the only data communications technology in recent times to be embraced by both the computer and telecommunications industries. Thus, ATM is a single solution for connectivity within a test center, across a test range, or between ranges. ATM can be implemented in an evolutionary manner as the needs develop. This means the rate of capital investment can be gradual and older technologies can be replaced slowly as they become the communications bottlenecks. However, success of this evolution requires some planning now. This paper provides an overview of ATM, its application to test ranges and telemetry distribution. A road map is laid out which can guide the evolutionary changeover from today's technologies to a full ATM communications infrastructure. Special applications such as the support of high performance multimedia workstations are presented.
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Manan, Jamalul-lail Abdul. "Performance evaluation of an FDDI-ATM gateway capable of supporting multi-class traffic." Thesis, University of Strathclyde, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322109.
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Alvarez, Isidro. "Development of a security network (SECNET) based on integrated services digital network (ISDN)." FIU Digital Commons, 1996. http://digitalcommons.fiu.edu/etd/2064.
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The progress in the computing and communication industries together with the fast evolution of the semiconductor industry has made possible advances in the communications field. These advances have been used by other related applications to improve the services that they bring about. On the other hand, business crimes have increased three digits orders of magnitude in one decade, making from 20% to 30% of small businesses fail. These conditions demand new solutions to make security systems more reliable and efficient.
The present work combines ISDN as a network with a security system to create a security network (SECNET). It will create intelligent and distributed security devices that communicate information from different places to a main security office by using the ISDN lines available at the premises. This work also introduces a new idea of individual equipment protection.
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Choi, Yiu Kuen. "Adaptive traffic regulation at the burst level for real time ATM applications." Thesis, University of Sunderland, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339543.
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Yu, Oliver T. W. "Integrated congestion management at the user-network interface of an ATM/B-ISDN network." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30126.
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This thesis presents an integrated congestion management platform of user traffic at the UNI of the ATM-based network considering the presence of signalling traffic. Integrated congestion management dictates that congestion control schemes are applied during the call access phase (call admission control scheme) and the information transfer phase (buffer control scheme) of user traffic source. The congestion control schemes are devised to meet the congestion performance requirements and to optimize the performance if possible.
UNI call admission and buffer controls developed for the conventional packet-switched network are not applicable to the ATM-based network because of the different input traffic characteristics. In most of the past investigations on the performance of conventional packet-switched networks, the individual input traffic is mostly computer-to-computer data; such individual and aggregate traffic are well-known to follow the Poisson process. On the other hand, ATM-based networks allow a variety of input traffic in addition to the Poisson-distributed traffic. In this thesis, individual user traffic process is modelled as a two-state Markov modulated Poisson process; the aggregate user traffic process is modeled as a batch Bernoulli renewal process under short-term condition and as a fluid process under long-term heavy traffic condition.
The signalling traffic at the UNI carries call control messages and network management
messages originated from the user nodes. The signalling traffic must be serviced quickly since they directly affect call establishment and network efficiency. Up to now, all related congestion control researches only consider user traffic. Consequently, the primary objective for this thesis is to study the effect of the higher-priority signalling
traffic on the multiplexing of user traffic at the UNI. A novel modeling of user traffic multiplexing through the ATM statistical multiplexer at the UNI is proposed: it is characterized
by a queueing model with random service disruptions due to the transport of higher priority signalling traffic.
The congestion performance requirements of the user traffic for the UNI are studied in terms of the stochastic cell loss requirement and the deterministic upper-bound cell delay requirement. However, in order to investigate the stochastic cell loss phenomenon due to buffer overflow, the stochastic queue behaviour must first be examined. Consequently, a novel algorithm to solve the stationary distribution of the queue length process under short-term heavy traffic and finite buffer capacity conditions is presented.
A novel UNI call admission control scheme is proposed, and its objective is to maintain the required network performance assigned to the UNI access-node by exerting call admission control in the call access phase of each user traffic source. It is analyzed using an input-limit static control model employing stochastic ordering between the cell loss ratio random variable and the desired threshold random variable as a criterion to decide if a new call should be admitted. The cell loss ratio random variable has been chosen as the performance objective rather than the long-term-time-averaged cell loss ratio, so as to take into account of the dynamic nature of bursty traffic sources.
A novel UNI intra-node buffer control scheme is proposed, and its objective is to optimize the network performance of the UNI access-node by exerting buffer control in the aggregate information transfer phase of the user traffic sources. It is analyzed by means of a sequential decision process model characterized by a stationary, Markovian and deterministic threshold control policy.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Prakash, Nisheeth. "The use of ISDN signaling for real-time applications at homes and small businesses." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ33825.pdf.
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MELO, Carlos Afonso Araújo. "Um sistema computacional para leitura e análise de mensagens ISUP do sistema móvel celular." Universidade Federal do Maranhão, 2002. http://tedebc.ufma.br:8080/jspui/handle/tede/317.
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Previous issue date: 2002-10-03In this work a system is proposed to minimize the time of search of possible flaws in messages ISUP. The entrance of the proposed system is represented by files containing messages of user's part ISDN, they can be from ACM (Address completes) to USR (User-to-user information). the exit of the proposed system is exhibited through another file containing the reads message and all your meaning, as well as an analysis of the translation. The results obtained show that the time for decoding is extremely reduced. The consideration presented generates taking of decision demonstrating the applicability of the proposed system.
Neste trabalho é proposto um sistema para minimizar o tempo de busca de possíveis falhas em mensagens ISUP. A entrada do sistema proposto é representada por arquivos contendo mensagens da parte de usuário ISDN, que podem ser desde a ACM (Address complete) até a USR (User-to-user information). A saída do sistema proposto é exibida através de um outro arquivo contendo a mensagem lida e todo o seu significado, assim como uma análise da tradução. Os resultados obtidos mostram que o tempo para decodicação é extremamente reduzido. A consideração apresentada gera tomada de decisão demonstrando a aplicabilidade do sistema proposto.
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Megemont, Marine. "Sensibilisation centrale trigéminale et interactions neurone/astrocyte dans un modèle de migraine chronique." Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAS017.
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La répétition des crises de migraine entraine une plasticité neuronale inadaptée et conduit à la chronicisation de la maladie. La sensibilisation des réseaux de la douleur joue un rôle important dans la transition vers les formes chroniques de la migraine. Il est reconnu que les astrocytes sont activés dans le noyau spinal caudal du trijumeau (Sp5C) en réponse à une lésion du tissu périphérique et sont impliqués dans la sensibilisation centrale. Nous faisons l’hypothèse que les astrocytes et la D-Sérine, un gliotransmetteur co-agoniste des récepteurs NMDA, participent à la sensibilisation centrale sous-jacente dans un modèle de migraine induite par un donneur d'oxyde nitrique (NO) chez le rat. En combinant des approches comportementales, immunohistochimiques, et électrophysiologiques in vivo, notre étude a montré le rôle de l'activité des astrocytes dans l'hypersensibilité cutanée céphalique et l'activation neuronale au sein du Sp5C. L'administration systémique répétée d'isosorbide dinitrate (ISDN), donneur de NO, induit une surexpression de p-ERK et de GFAP dans le Sp5C, une allodynie céphalique mécanique persistante et une facilitation des réponses liées à l’activation des fibres C des neurones du Sp5C. Nous démontrons pour la première fois que l'application intracisternale d'acide L-α-aminoadipique (gliotoxine) et de D-Amino-Acid-Oxidase (enzyme dégradant la D-sérine) empêche l'allodynie et la sensibilisation du Sp5C. Cet effet préventif était supprimé par l'administration de D-sérine. Nos résultats suggèrent que les astrocytes contribuent à la sensibilisation centrale du trijumeau et à l'hypersensibilité cutanée céphalique qui caractérisent la progression de la migraine. Ils montrent que l'altération de l'activité des astrocytes pourrait constituer un nouvel élément clé dans les mécanismes physiopathologiques de la migraineRepeated migraine attacks are associated with maladaptive neural plasticity and lead to chronic headache. Sensitization of pain networks play an important role in the transition to the chronic forms of the disorder. It is increasingly recognized that astrocytes are activated in the spinal trigeminal nucleus caudalis (Sp5C) in response to peripheral tissue injury and are involved in central sensitization. Here, we hypothetized that astrocytes and D-Serine, an astroglial neurochemical and NMDA co-agonist, participate in the central sensitization underlying a NO-donor-induced migraine model in the rat. Combining behavioral, immunohistochemical and in vivo electrophysiological approaches, our study proved the contribution of astrocytes activity in cephalic cutaneous hypersensitivity and neuronal activation within the MDH. Recurrent systemic administration of isosorbide dinitrate (ISDN), a nitric oxide donor, induce an overexpression of p-ERK and GFAP in Sp5C, a persistent cephalic mechanical allodynia and facilitated C-fiber-electrically-evoked responses of Sp5C neurons. We demonstrate for first time that intracisternal application of L-α-Aminoadipic acid (gliotoxin) and D-Amino-Acid-Oxidase (D-Serine degrading enzyme) prevented allodynia and trigeminal sensitization, but this preventive effect was abolished by D-serine administration. Our results suggest that astrocytes contribute to the trigeminal central sensitization and cephalic cutaneous hypersensitivity that characterize the migraine progression. They show that alteration of astrocyte activity could be a new key element in the pathophysiological mechanisms of migraine
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Schwarz, Albrecht. "Modellierung und Bewertung von Verfahren zur Last- und Leistungsregelung in Steuereinheiten von B-ISDN-, ATM-Vermittlungssystemen /." Stuttgart : Inst. für Nachrichtenvermittlung und Datenverarbeitung, 2002. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009999625&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Arias, Christopher V. "An evaluation of B-ISDN for the communication architecture requirements of Distributed Interactive Simulation (DIS)." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA280783.
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Thesis (M.S. in Information Technology Management) Naval Postgraduate School, March 1994.Thesis advisor(s): Carl R. Jones, Myung W. Suh. "March 1994." Bibliography: p. 58-59. Also available online.
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Hage, Mirna. "A study of a symbol-rate timing recovery algorithm for a digital ISDN U-transceiver." Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/5590.
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A symbol rate timing recovery scheme suitable for ISDN transmission on digital subscriber loops is investigated. Four timing estimates based on this scheme are studied for steady-state and convergence behavior. Theoretical analysis and simulation results are included. The effect of the various system parameters such as channel distortion, noise and dead-zone threshold is examined for the four timing estimates. Their performance on realistic loops in a practical U-transceiver using 2B1Q line code is characterized and compared. The performance will be evaluated principally by the receiver convergence, steady-state timing jitter and noise margin allowed before convergence is lost.
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Wu, Jiyong. "Contribution a l'etude d'une chaine de telecommunication privee haut debit a integration de services (b-isdn)." Paris, ENST, 1991. http://www.theses.fr/1991ENST0020.
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La chaine de telecommunication privee haut debit presentee est constituee de plusieurs elements: le terminal multimedia, le commutateur prive haut debit, le reseau optique et le commutateur aim comme nud du reseau. Les objectifs principaux de cette conception sont: a) introduire de nouveaux services dans le domaine prive comme messagerie vocale visiophone, videoconference. . . ; b) etendre la limite geographique et la connectivite des systemes et des reseaux existants: c) experimenter et valider les technologiques nouvelles: d) mesurer de facon quantitative les besoins reels de nouveaux services. La contribution a cette etude se divise en 5 parties: 1) proposition et etude des paquetiseurs et d'un multiplexeur de paquets pour le terminal multimedia; 2) definition d'un nouveau commutateur prive haut debit multiservices (avec des brevets europeens). Ses performances sont etablies par modelisation et simulation; 3) etude de la politique de l'allocation des canaux en mode circuit envisagee pour fddi-ii et qpsx. Ensuite, proposition des politiques nouvelles afin d'ameliorer les performances; 4) etude de deux files d'attente en competition avec capacite finie et application pour la definition des schemas de priorite de transmission dans l'interconnexion des pbx haut debit et des reseaux locaux; 5) performance d'un commutateur atm pour les services video
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Darmaros, Theodore. "Implementing the Integrated Services Digital Network (ISDN) : prospects and problems in the realisation of a telecommunications concept." Thesis, University of Sussex, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297115.
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The present thesis discusses the interrelation between technical change, institutional transformation and public policy in the context of the planning and early development of new public telecommunications infrastructures. Efforts to implement ISDN have featured prominently in the above developments during the 1980s, thus offering the empirical ground on which the thesis focuses. Specifically, the thesis aims to identify the main critical factors that have been shaping the realisation of ISDN nationally and internationally and assess their impact in its early commercialisation stage. A number of analytical concepts provide the background for the above exercise: the Schumpeterian "creative destruction" and its variants; the notion of complementarity between technical change and institutional restructuring; different classifications of the innovation process; the ideas of technological paradigms and trajectories; the role of user-producer relations. ISDN is assessed in view of the broader transformations that have revolutionised the telecommunications industry during the 1980s. The innovative record of "technical trends" and socio-technical "concepts" examined by the thesis supports the case for technological pluralism. Their presence opens a variety of implementation alternatives for policy makers and defies the technological determinism strongly present in the original versions of the ISDN concept. Moreover, the spectrum of liberalisation regulatory options analysed, creates radically different conditions for the realisation of ISDN from the monopoly environment it was conceived in. As a result, ISDN is forced to change, adapting to a competitive, "open network" environment. The thesis examines the specific experiences of ISDN implementation in the United States, Japan and the European Community (France, Germany and the U.K., plus policies promoted by the European Commission) for its early diffusion period (up to 1990). It is demonstrated that ISDN has been pushed by telecommunications suppliers as part of both their longer-term strategic plans as well as their shorter-term tactical moves. Yet supply push, including international standardisation efforts, has been unable to offer success alone. A weak user participation, later realised by some providers; a slow and complex adaptation of ISDN to the new regulatory realities; difficulties to identify "winning" commercial applications for the right markets. These are the most important problem factors in ISDN's smooth commercialisation, although with varying impact in different national environments.
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Riley, Thomas A. D. (Thomas Atkin Denning) Carleton University Dissertation Engineering Electrical. "A comparison of implementation aspects in oversampled analog to digital converters for use in ISDN subscriber loops." Ottawa, 1989.
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Wu, Jiyong. "Contribution à l'étude d'une chaîne de télécommunication privée haut débit à intégration de services (B-ISDN) : version non confidentielle /." Paris : École nationale supérieure des télécommunications, 1991. http://catalogue.bnf.fr/ark:/12148/cb355858407.
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Queiroz, Edvanina de Sousa Costa. "Efeito do óxido nítrico sobre fêmures e vértebras lombares de ratos orquiectomizados." Universidade Federal de São Carlos, 2007. https://repositorio.ufscar.br/handle/ufscar/1199.
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Previous issue date: 2007-07-15Financiadora de Estudos e Projetos
Osteoporosis is attributed to an imbalance between bone formation and resorption, followed by bone mass loss and microarchitectural deterioration, leading to increased bone fragility and fracture risk. Nitric oxide (NO) is a signaling molecule with important regulatory effects on bone cell function. Nitric oxide donor nitroglycerin has been reported to alleviate ovariectomy-induced and corticosteroid-induced bone loss. The aim of the present study was to investigate the effect of NO on cancellous and cortical bone of orchiectomized rats. A total of 98 male Wistar rats (four months old) were randomly divided in the following groups - Experiment I: intact treated with saline (stomacal gavage - gv), orchiectomized treated with saline (gv), and orchiectomized treated with NO donor isosorbide dinitrate - ISDN (gv); Experiment II: intact treated with saline (subcutaneous injection - sc), orchiectomized treated with saline (sc), and orchiectomized treated with NO synthase inhibitor NG-nitro-L-arginine-methylester - L-NAME (sc); Experiment III: intact treated with saline (intraperitoneous injection - ip), orchiectomized treated with saline (ip), and orchiectomized treated with NO precursor L-arginine (ip); Basal group: one group was killed at the beginning of the study (four months old) and served as a baseline group. The animals were killed after 8 weeks of treatment. At death, both femurs and lumbar vertebrae (L5-6) were obtained from each rat, and changes in both cancellous and cortical bone mass and biomechanical competence were assessed. The treatment with NO donor isosorbide dinitrate protected the cortical bone mass of adult rats from the deleterious effects of castration. The protective effect of ISDN treatment on the cancellous bone mass was not as significant as the one observed on the cortical bone. The L-NAME treatment did not increase the deleterious effects induced by orchiectomy in both cancellous and cortical bone mass. No effect was observed with the L-arginine treatment, in the dose used in this study. In conclusion, this study suggest that NO donor isosorbide dinitrate can be used in the future as an alternative pharmacological strategy for the prevention of androgen deficiency osteoporosis, in men with proven hypogonadism and in eugonadal men.
A osteoporose é atribuída a um desequilíbrio entre a reabsorção e a formação óssea, seguido por perda de massa óssea e deterioração da microarquitetura óssea, levando ao aumento da fragilidade óssea e do risco de fraturas. O óxido nítrico (NO) é uma molécula sinalizadora com efeito regulatório importante sobre a função celular óssea. A nitroglicerina, um doador de NO, tem sido mostrada como uma substância eficiente para atenuar perdas ósseas induzidas por ovariectomia e por corticosteróide. O objetivo do presente estudo foi investigar o efeito do NO sobre o osso trabecular e o osso cortical de ratos orquiectomizados. Um total de noventa e oito ratos Wistar com quatro meses de idade foram aleatoriamente divididos nos seguintes grupos: Experimento 1 = intactos tratados com salina (gavagem estomacal - gv), orquiectomizados tratados com salina (gv), orquiectomizados tratados com o doador de NO dinitrato de isossorbida ISDN (gv); Experimento 2 = intactos tratados com salina (subcutânea - sc), orquiectomizados tratados com salina (sc), orquiectomizados tratados com o inibidor da síntese de NO NG-nitro-L-arginina-metil ester - L-NAME (sc); Experimento 3 = intactos tratados com salina (intraperitonial -ip), orquiectomizados tratados com salina (ip), orquiectomizados tratados com o precursor de NO L-Arginina - L-ARG (ip); Basal, um grupo foi sacrificado no início do estudo (quatro meses de idade) para servir como linha de base. Os animais foram sacrificados por decapitação após oito semanas de tratamento. Os fêmures e as vértebras lombares (L5 e L6) foram retiradas de cada animal para verificação das mudanças que ocorreram na massa óssea e competência biomecânica do osso trabecular e cortical de cada grupo experimental. O tratamento com o doador de NO, ISDN, preveniu os efeitos deletérios da orquiectomia sobre o osso cortical e atenuou estes efeitos sobre o osso trabecular. O tratamento com L-NAME não intensificou o efeito osteopênico da castração e ainda amenizou tal efeito tanto no osso cortical quanto no osso trabecular. A suplementação com L-arginina realizada durante o período de oito semanas, na dose utilizada, não produziu efeitos significativos. Em conclusão, este estudo sugere que o doador de NO dinitrato de isossorbida pode ser usado no futuro como uma estratégia farmacológica alternativa para a prevenção de osteoporose causada por deficiência androgênica, que acomete homens portadores de hipogonadismo ou são submetidos a orquiectomia.
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Shankaran, Rajan, University of Western Sydney, and School of Computing and Information Technology. "Asynchronous transfer mode security." THESIS_XXX_CIT_Shankaran_R.xml, 1999. http://handle.uws.edu.au:8081/1959.7/252.
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There is a growing interest in the development of broadband services and networks for commercial use in both local area and wide area networks. The primary reasons for this is a pressing need to meet the demand for increased bandwidth for remote sites interconnection, and in high speed data transfer of bulk data such as images etc. There has also been a significant change in the characteristics of network traffic. It is increasingly taking the form of bursty traffic characterized by an unpredictable demand for bandwidth of several megabytes. A new generation of networking technologies have emerged to meet the demand of growing and uncertain bandwidth requirements. One such technology is called Asynchronous Transfer Mode (ATM) for use on broadband networks under the banner of broadband ISDN. ATM enables interconnection at high speeds in the range of Mbit/s or Gbit/s over wide areas, which effectively moves the bottleneck from networks to end systems. Furthermore, the user is able to access bandwidth on demand and the user is only charged for the bandwidth actually used. As more and more information (audio, image and data) is transferred over ATM networks, security issues are becoming increasingly critical. The rapidly growing use of the Internet to transfer confidential and sensitive information only enhances the importance of security services. One may even argue that the success of ATM will be determined not by its cost effectiveness but also to the level of trust that can be placed on its performance, security and availability. The objective of this dissertation is to address the issues involved in the design of security services for ATM networks.Master of Science (Hons)
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Ramesh, Rajaram Posner Edward C. Posner Edward C. "Efficient multichannel methods for high-rate data transmission with application to ISDN (or) pouring water to get more out of copper /." Diss., Pasadena, Calif. : California Institute of Technology, 1992. http://resolver.caltech.edu/CaltechETD:etd-08082007-081649.
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Andrén, Åse Larsen, Tove Mantzakanis, and Maria Blom. "Säkerhets lösning för elektronisk faktura." Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik och datavetenskap, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1440.
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We have chosen to look closer at the area of security for electronic invoices. The purpose of this inquest is to provide our case study with a security analysis of three suggestions and a recommendation of the best solution, according to our test. The three solutions are ISDN via a third party, X.25 via Internet bank and Mail server. The company in our case study is in this report referred to as X, has a strong market position and a large clientele and therefore we were interested in analysing and improving X?s electronic invoice system. X was in the position of testing an electronic invoicing system towards a selective group of business customers. The major problem with the system was the security issue regarding transferring the file.
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Sekercioglu, Ahmet, and ahmet@hyperion ctie monash edu au. "Fuzzy logic control techniques and structures for Asynchronous Transfer Mode (ATM) based multimedia networks." Swinburne University of Technology, 1999. http://adt.lib.swin.edu.au./public/adt-VSWT20050411.130014.
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The research presented in this thesis aims to demonstrate that fuzzy logic is a useful tool for developing mechanisms for controlling traffc flow in ATM based multimedia networks to maintain quality of service (QoS) requirements and maximize resource utilization. The study first proposes a hierarchical, multilevel control
structure for ATM networks to exploit the reported strengths of fuzzy logic at various
control levels. Then, an extensive development and evaluation is presented for a subset of the proposed control architecture at the congestion control level.
An ATM based multimedia network must have quite sophisticated traffc control capabilities to effectively handle the requirements of a dynamically varying mixture of voice, video and data services while meeting the required levels of performance.
Feedback control techniques have an essential role for the effective and efficient management of the resources of ATM networks. However, development of conventional feedback control techniques relies on the availability of analytical system models. The characteristics of ATM networks and the complexity of service
requirements cause the analytical modeling to be very difficult, if not impossible.
The lack of realistic dynamic explicit models leads to substantial problems in developing
control solutions for B-ISDN networks. This limits the ability of conventional techniques to directly address the control objectives for ATM networks. In the literature, several connection admission and congestion control methods for B-ISDN networks have been reported, and these have achieved mixed success. Usually they either assume heavily simplified models, or they are too complicated to implement, mainly derived using probabilistic (steady-state) models.
Fuzzy logic controllers, on the other hand, have been applied successfully to the task of controlling systems for which analytical models are not easily obtainable.
Fuzzy logic control is a knowledge-based control strategy that can be utilized when an explicit model of a system is not available or, the model itself, if available, is highly complex and nonlinear. In this case, the problem of control system design is based on qualitative and/or empirically acquired knowledge regarding the operation of the system. Representation of qualitative or empirically acquired knowledge in a fuzzy logic controller is achieved by linguistic expressions in the form of fuzzy relational equations. By using fuzzy relational equations, classifications related to system parameters can be derived without explicit description.
The thesis presents a new predictive congestion control scheme, Fuzzy Explicit Rate Marking (FERM), which aims to avoid congestion, and by doing so minimize the cell losses, attain high server utilization, and maintain the fair use of links.
The performance of the FERM scheme is extremely competitive with that of control schemes developed using traditional methods over a considerable period of time.
The results of the study demonstrate that fuzzy logic control is a highly effective design tool for this type of problems, relative to the traditional methods. When controlled systems are highly nonlinear and complex, it keeps the human insight alive and accessible at the lower levels of the control hierarchy, and so higher levels
can be built on this understanding.
Additionally, the FERM scheme has been extended
to adaptively tune (A-FERM) so that continuous automatic tuning of the parameters can be achieved, and thus be more adaptive to system changes leading to better utilization of network bandwidth. This achieves a level of robustness that is not exhibited by other congestion control schemes reported in the literature.
In this work, the focus is on ATM networks rather than IP based networks. For historical reasons, and due to fundamental philosophical differences in the (earlier) approach to congestion control, the research for control of TCP/IP and ATM based networks proceeded separately. However, some convergence between them has recently become evident. In the TCP/IP literature proposals have appeared on active queue management in routers, and Explicit Congestion Notication (ECN) for IP. It is reasonably expected that, the algorithms developed in this study will be applicable to IP based multimedia networks as well.
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Bundick, Steven N., and Steven E. Kremer. "THE IMPLEMENTATION OF NASA’s LOW EARTH ORBITER – TERMINAL AS AN AUTONOMOUS GROUND NETWORK ASSET." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/608519.
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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, NevadaAs part of NASA’s goal to reduce costs for satellite telemetry and command ground support, the ground network has installed two autonomous ground terminals known as Low Earth Orbiter - Terminal’s, or LEO-T’s. These systems are highly automated and were developed to prove the feasibility of supporting multi-mission satellites in a handsoff mode.
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Villegas, Ruben M. M. "Statistical processing for telecommunication networks applied to ATM traffic monitoring." Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/6760.
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Within the fields of network operation and performance measurement, it is a common requirement that the technologies involved must provide the basis for an effective, reliable, measurable and controllable service. In order to comply with the service performance criteria, the constrains often lead to very complex techniques and methodologies for the simulation, control, test, and measurement processes. This thesis addresses some of the factors that contribute to the overall spectrum of statistical performance measurements in telecommunication services. Specifically, it is concerned with the development of three low complexity and effective techniques for real-time traffic generation, control and measurement. These techniques have proved to be accurate and near optimum. In the three cases the work starts with a literature survey of known methodologies, and later new techniques are proposed and investigated by simulating the processes involved. The work is based on the use of high-speed Asynchronous Transfer Mode (ATM) networks. The problem of developing a fast traffic generation technique for the simulation of Variable Bit Rate traffic sources is considered in the first part of this thesis. For this purpose, statistical measures are obtained from the analysis of different traffic profiles or from the literature. With the aid of these measures, a model for the fast generation of Variable Bit Rate traffic at different time resolutions is developed. The simulated traffic is then analysed in order to obtain the equivalent set of statistical measures and these are compared against those observed in real traffic traces. The subject of traffic control comprises a very wide area in communication networks. It refers to the generalised classification of actions such as Connection Admission and Flow Control, Traffic Policing and Shaping. In the second part of this thesis, a method to modify the instantaneous traffic profile of a variable rate source is developed. It is particularly useful for services which have a hard bound on the cell loss probability, but a soft bound on the admissible delay, matching the characteristics of some of the services provided by ATM networks. Finally, this thesis is also concerned with a particular aspect of the operation and management of high speed networks, or OAM functions plane, namely with the monitoring of network resources. A monitoring technique based on numerical approximation and statistical sampling methods is developed and later used to characterise a particular traffic stream, or a particular connection, within a high speed network. The resulting algorithms are simple and computationally inexpensive, but effective and accurate at the same time, and are suitable for real-time processing.
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Forchel, Dirk, and Rainer G. Spallek. "VLSI-Realisierungen für ATM: eine Übersicht." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-98769.
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Der Asynchronous Transfer Mode (ATM) stellt die zukünftige und einheitliche Basistechnologie für das Breitband-ISDN dar. Da nahezu alle wesentlichen Protokollfunktionen in Hardware realisierbar sind, soll nachfolgend ein Überblick über bereits angebotene VLSI-Schaltkreise gegeben werden. Eine Systematisierung und Einordnung vorhandener ATM-Chips hinsichtlich ihrer Leistungsfähigkeit und ihres Funktionsumfangs erfolgt in Hinblick auf das sogenannte B-ISDN-Referenzmodell. Dieses Schichtenmodell definiert die notwendigen Protokolle und Schnittstellen für den Asynchronous Transfer Mode. Zum grundlegenden Verständnis wird einleitend eine kurze Einführung in die Basisprinzipien von ATM gegeben.
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Forchel, Dirk, and Rainer G. Spallek. "VLSI-Realisierungen für ATM: eine Übersicht." Technische Universität Dresden, 1997. https://tud.qucosa.de/id/qucosa%3A26201.
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Der Asynchronous Transfer Mode (ATM) stellt die zukünftige und einheitliche Basistechnologie für das Breitband-ISDN dar. Da nahezu alle wesentlichen Protokollfunktionen in Hardware realisierbar sind, soll nachfolgend ein Überblick über bereits angebotene VLSI-Schaltkreise gegeben werden. Eine Systematisierung und Einordnung vorhandener ATM-Chips hinsichtlich ihrer Leistungsfähigkeit und ihres Funktionsumfangs erfolgt in Hinblick auf das sogenannte B-ISDN-Referenzmodell. Dieses Schichtenmodell definiert die notwendigen Protokolle und Schnittstellen für den Asynchronous Transfer Mode. Zum grundlegenden Verständnis wird einleitend eine kurze Einführung in die Basisprinzipien von ATM gegeben.