Presents a new category of optical CDMA systems which work based on spectral encoding. In such systems, that the authors refer to as frequency-encoded CDMA (FE-CDMA) systems, the coding is done in the frequency domain while in the usual CDMA systems the code multiplies the modulation signal in the time domain. They present a new type of FE-CDMA system, based on encoding noncoherent broadband sources. They discuss the advantages of the system compared to other optical CDMA systems and present its performance. They show that very efficient, low-cost, CDMA systems can be obtained with an aggregate throughput of many gigabits per second. Also, for this system, the spreading gain of CDMA is independent of the modulation bandwidth. Hence, the system can accommodate variable bit rates, naturally. >

Optical code-division-multiplexed systems based on spectral encoding of noncoherent sources

A new model of nonuniform traffic is introduced for a single-hop packet-switching system. This traffic model allows arbitrary traffic streams subject only to a constraint on the number of data packets which can arrive at any, individual source in the system or for any individual destination in the system over time periods of specified length. The nonuniform traffic model is flexible enough to cover integrated data networks carrying diverse classes of data. The system model is rather general, and includes passive optical star wavelength-division networks. Transmission algorithms are introduced for a single-hop packet-switching system with such nonuniform traffic and with propagation delay that is negligible relative to the packet length. The algorithms are based on collision-free scheduling of packets using graph-matching algorithms since the global state of the system is known to all stations at any time.

Scheduling nonuniform traffic in a packet-switching system with small propagation delay

The rapid development of Asynchronous Transfer Mode technology in the last 10-15 years has stimulated renewed interest in the design and analysis of switching systems, leading to new ideas for system designs and new insights into the performance and evaluation of such systems. As ATM moves closer to realizing the vision of ubiquitous broadband ISDN services, the design of switching systems takes on growing importance. This paper seeks to clarify the key architectural issues for ATM switching system design and provides a survey of the current state-of-the-art.

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Architectural choices in large scale ATM switches

From the Publisher:
Complete and comprehensive coverage of packet switching concepts and technologies 
The rapid growth of Internet traffic has spurred a new concentration on IP routers and ATM, MPLS, and optical switches. This book addresses the basics, theory, architectures, and technologies for implementing ATM switches and IP routers. It focuses on the architecture for the next generation of broadband switches and routers and provides detailed treatment of both theoretical and practical topics for professionals and students alike. 
Broadband Packet Switching Technologies is written with engineers and industry researchers in mind. It describes the basic concepts and fundamentals of ATM switches and IP routers, then divides the switches into different categories. In each category, the authors discuss the operations, problems, strengths, and weaknesses of the switches in performance and implementation. Detailed solutions and algorithms are also provided. The authors also extend fundamental packet-switching concepts to wireless and fiber-optic networks. 
Broadband Packet Switching Technologies fills the need for a textbook and reference dedicated to high-speed networking technologies that serves the specific needs of professionals in the telecommunications industry and provides expert material for students in related fields.

Broadband Packet Switching Technologies: A Practical Guide to ATM Switches and IP Routers

The architecture of an asynchronous transfer mode (ATM) switching system for prototype applications is presented. The general concept to upgrade the existing ISDN switch with an ATM module is introduced, and the building blocks of this ATM module are described in detail. Switching of ATM cells is performed in a single application-specific integrated circuit (ASIC). ASICs can be cascaded to form large switching modules. Peripheral modules interface the ATM switch to external transmission systems and perform all ATM-related functions, including means for redundancy of the switching network. The redundancy scheme tolerates single failures without affecting the user information. A switching network architecture is shown to be capable of fulfilling varying demands in terms of the number of ports for ATM switches and cross connects, concentrators, and multiplexers. >

A scalable ATM switching system architecture

The authors consider the generic problem of designing a large N*N(N>1000) high-performance, broadband packet (or asynchronous transfer mode) switch. They provide ways to construct arbitrarily large switches out of modest-size packet switches, without sacrificing overall delay/throughput performance. They propose and study a growable switch architecture based on three key principles: (a) a generalized knockout principle which exploits the statistical behavior of packet arrivals and thereby reduces the interconnect complexity; (b) output queuing, which yields the best possible delay/throughput performance; and (c) distributed intelligence in routing packets through the interconnect fabric. Other features include the guarantee of a first-in first-out packet sequence, broadcast and multicast capabilities, and compatibility with variable-length packets. In a broadband ISDN (integrated services digital network) example, the authors show a 2048*2048 switch configuration with building blocks of 42*16 packet switch modules and 128*128 interconnect modules. >

Y.S. Yeh

Papers

A growable packet (ATM) switch architecture: design principles and applications