9 research outputs found

    The Strict-Sense Nonblocking Multirate l

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    This paper considers the nonblocking conditions for a multirate logd(N,0,p) switching network at the connection level. The necessary and sufficient conditions for the discrete bandwidth model, as well as sufficient and, in particular cases, also necessary conditions for the continuous bandwidth model, were given. The results given for dn-1/2f0≄f1+1 in the discrete bandwidth model are the same as those proposed by Hwang et al. (2005); however, in this paper, these results were extended to other values of f0, f1, and d. In the continuous bandwidth model for B+b>1, the results given in this paper are also the same as those by Hwang et al. (2005); however, for B+b≀1, it was proved that a smaller number of vertically stacked logdN switching networks are needed

    Information Switching Processor (ISP) contention analysis and control

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    Future satellite communications, as a viable means of communications and an alternative to terrestrial networks, demand flexibility and low end-user cost. On-board switching/processing satellites potentially provide these features, allowing flexible interconnection among multiple spot beams, direct to the user communications services using very small aperture terminals (VSAT's), independent uplink and downlink access/transmission system designs optimized to user's traffic requirements, efficient TDM downlink transmission, and better link performance. A flexible switching system on the satellite in conjunction with low-cost user terminals will likely benefit future satellite network users

    Multicast cross-path ATM switches: principles, designs and performance evaluations.

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    by Lin Hon Man.Thesis (M.Phil.)--Chinese University of Hong Kong, 1998.Includes bibliographical references (leaves 59-[63]).Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Organization of Thesis --- p.3Chapter 2 --- Principles of Multicast Cross-Path Switches --- p.4Chapter 2.1 --- Introduction --- p.4Chapter 2.2 --- Unicast Cross-Path switch --- p.5Chapter 2.2.1 --- Routing properties in Clos networks --- p.5Chapter 2.2.2 --- Quasi-static routing procedures --- p.5Chapter 2.2.3 --- Capacity and Route Assignment --- p.7Chapter 2.3 --- Multicast Cross-Path Switch --- p.8Chapter 2.3.1 --- Scheme 1 - Cell replication performed at both input and output stages --- p.10Chapter 2.3.2 --- Scheme 2 - Cell replication performed only at the input stage --- p.10Chapter 3 --- Architectures --- p.14Chapter 3.1 --- Introduction --- p.14Chapter 3.2 --- Input Module Design (Scheme 1) --- p.16Chapter 3.2.1 --- Input Header Translator --- p.16Chapter 3.2.2 --- Input Module Controller --- p.17Chapter 3.2.3 --- Input Replication Network (Scheme 1) --- p.19Chapter 3.2.4 --- Routing Network --- p.23Chapter 3.3 --- Central Modules --- p.24Chapter 3.4 --- Output Module Design (Scheme 1) --- p.24Chapter 3.5 --- Input Module Design (Scheme 2) --- p.25Chapter 3.5.1 --- Input Header Translator (Scheme 2) --- p.26Chapter 3.5.2 --- Input Module Controller (Scheme 2) --- p.27Chapter 3.5.3 --- Input Replication Network (Scheme 2) --- p.28Chapter 3.6 --- Output Module Design (Scheme 2) --- p.29Chapter 4 --- Performance Evaluations --- p.31Chapter 4.1 --- Introduction --- p.31Chapter 4.2 --- Traffic characteristics --- p.31Chapter 4.2.1 --- Fanout distribution --- p.31Chapter 4.2.2 --- Middle stage traffic load and its calculation --- p.32Chapter 4.3 --- Throughput Performance --- p.34Chapter 4.4 --- Delay Performance --- p.37Chapter 4.4.1 --- Input Stage Delay --- p.38Chapter 4.4.2 --- Output Stage Delay --- p.39Chapter 4.5 --- Cell Loss Performance --- p.43Chapter 4.5.1 --- Cell Loss due to Buffer Overflow --- p.44Chapter 4.5.2 --- Cell Loss Due to Output Contention --- p.45Chapter 4.6 --- Complexities --- p.50Chapter 5 --- Conclusions --- p.57Bibliography --- p.5

    Performance study of multirate circuit switching in quantized clos network.

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    by Vincent Wing-Shing Tse.Thesis submitted in: December 1997.Thesis (M.Phil.)--Chinese University of Hong Kong, 1998.Includes bibliographical references (leaves 62-[64]).Abstract also in Chinese.Chapter 1 --- Introduction --- p.1Chapter 2 --- Principles of Multirate Circuit Switching in Quantized Clos Network --- p.10Chapter 2.1 --- Formulation of Multirate Circuit Switching --- p.11Chapter 2.2 --- Call Level Routing in Quantized Clos Network --- p.12Chapter 2.3 --- Cell Level Routing in Quantized Clos Network --- p.16Chapter 2.3.1 --- Traffic Behavior in ATM Network --- p.17Chapter 2.3.2 --- Time Division Multiplexing in Multirate Circuit Switching and Cell-level Switching in ATM Network --- p.19Chapter 2.3.3 --- Cell Transmission Scheduling --- p.20Chapter 2.3.4 --- Capacity Allocation and Route Assignment at Cell-level --- p.29Chapter 3 --- Performance Evaluation of Different Implementation Schemes --- p.31Chapter 3.1 --- Global Control and Distributed Switching --- p.32Chapter 3.2 --- Implementation Schemes of Quantized Clos Network --- p.33Chapter 3.2.1 --- Classification of Switch Modules --- p.33Chapter 3.2.2 --- Bufferless Switch Modules Construction Scheme --- p.38Chapter 3.2.3 --- Buffered Switch Modules Construction Scheme --- p.42Chapter 3.3 --- Complexity Comparison --- p.44Chapter 3.4 --- Delay Performance of The Two Implementation Schemes --- p.47Chapter 3.4.1 --- Assumption --- p.47Chapter 3.4.2 --- Simulation Result --- p.50Chapter 4 --- Conclusions --- p.59Bibliography --- p.6

    On-board B-ISDN fast packet switching architectures. Phase 1: Study

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    The broadband integrate services digital network (B-ISDN) is an emerging telecommunications technology that will meet most of the telecommunications networking needs in the mid-1990's to early next century. The satellite-based system is well positioned for providing B-ISDN service with its inherent capabilities of point-to-multipoint and broadcast transmission, virtually unlimited connectivity between any two points within a beam coverage, short deployment time of communications facility, flexible and dynamic reallocation of space segment capacity, and distance insensitive cost. On-board processing satellites, particularly in a multiple spot beam environment, will provide enhanced connectivity, better performance, optimized access and transmission link design, and lower user service cost. The following are described: the user and network aspects of broadband services; the current development status in broadband services; various satellite network architectures including system design issues; and various fast packet switch architectures and their detail designs

    Switching techniques for broadband ISDN

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    The properties of switching techniques suitable for use in broadband networks have been investigated. Methods for evaluating the performance of such switches have been reviewed. A notation has been introduced to describe a class of binary self-routing networks. Hence a technique has been developed for determining the nature of the equivalence between two networks drawn from this class. The necessary and sufficient condition for two packets not to collide in a binary self-routing network has been obtained. This has been used to prove the non-blocking property of the Batcher-banyan switch. A condition for a three-stage network with channel grouping and link speed-up to be nonblocking has been obtained, of which previous conditions are special cases. A new three-stage switch architecture has been proposed, based upon a novel cell-level algorithm for path allocation in the intermediate stage of the switch. The algorithm is suited to hardware implementation using parallelism to achieve a very short execution time. An array of processors is required to implement the algorithm The processor has been shown to be of simple design. It must be initialised with a count representing the number of cells requesting a given output module. A fast method has been described for performing the request counting using a non-blocking binary self-routing network. Hardware is also required to forward routing tags from the processors to the appropriate data cells, when they have been allocated a path through the intermediate stage. A method of distributing these routing tags by means of a non-blocking copy network has been presented. The performance of the new path allocation algorithm has been determined by simulation. The rate of cell loss can increase substantially in a three-stage switch when the output modules are non-uniformly loaded. It has been shown that the appropriate use of channel grouping in the intermediate stage of the switch can reduce the effect of non-uniform loading on performance

    Modelling, Dimensioning and Optimization of 5G Communication Networks, Resources and Services

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    This reprint aims to collect state-of-the-art research contributions that address challenges in the emerging 5G networks design, dimensioning and optimization. Designing, dimensioning and optimization of communication networks resources and services have been an inseparable part of telecom network development. The latter must convey a large volume of traffic, providing service to traffic streams with highly differentiated requirements in terms of bit-rate and service time, required quality of service and quality of experience parameters. Such a communication infrastructure presents many important challenges, such as the study of necessary multi-layer cooperation, new protocols, performance evaluation of different network parts, low layer network design, network management and security issues, and new technologies in general, which will be discussed in this book
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