The authors propose a large asynchronous transfer mode (ATM) switch architecture based on memory switches of the type being developed by several research groups and on optical star couplers. Fast contention resolution makes it possible to combine a number of these modules, memory switches, and optical stars in order to attain a capacity of 2.5 Tb/s. This switch architecture has a relatively small failure group size of 128 STS-3 lines out of a total of 16384. The scaling of the switch to smaller capacities is discussed, showing how tradeoffs in the various parameters can be used to overcome particular technological limitations. Fault tolerance and recovery schemes are presented, showing that with minimal increase to the switch complexity and cost, a very reasonable fault recovery scheme is available for almost every sort of failure.>

The very broad bandwidth of low-loss optical transmission in a single-mode fiber and the recent improvements in single-frequency tunable lasers have stimulated significant advances in dense wavelength division multiplexed optical networks. This technology, including wavelength-sensitive optical switching and routing elements and passive optical elements, has made it possible to consider the use of wavelength as another dimension, in addition to time and space, in network and switch design. The independence of optical signals at different wavelengths makes this a natural choice for multiple-access networks, for applications which benefit from shared transmission media, and for networks in which very large throughputs are required. Recent progress in multiwavelength networks are reviewed, some of the limitations which affect the performance of such networks are discussed, and examples of several network and switch proposals based on these ideas are presented. Discussed also are critical technologies that are essential to progress in this field.>

For pt.I see ibid., vol.37, no.8, p.824-33 (1989). In Part I a technique based on optical orthogonal codes was presented to establish a fiber-optic code-division multiple-access (FO-CDMA) communications system. The results are used to derive the bit error rate of the proposed FO-CDMA system as a function of data rate, code length, code weight, number of users, and receiver threshold. The performance characteristics for a variety of system parameters are discussed. A means of reducing the effective multiple-access interference signal by placing an optical hard-limiter at the front end of the desired optical correlator is presented. Performance calculations are shown for the FO-CDMA with an ideal optical hard-limiter, and it is shown that using an optical hard-limiter would, in general, improve system performance.>

Integrated optics and optoelectronics will play key roles in the evolution of the telecommunications network. We briefly review the available and developing technologies for integrated optical and optoelectronic devices, and summarize their characteristics and their natural areas of application in telecommunications. We then describe the trends and developments in fiber communication systems, services, and architectures, and how they can benefit from these devices. Major areas in which these devices are expected to contribute are: lowering the costs of high-speed network termination equipment to aid in providing inexpensive wide-band services to the subscriber; increasing the fraction of the fiber's natural bandwidth that can be made available for network usage; and increasing the network flexibility to facilitate multiservice integration.