We describe some of the results of the Advanced Research Projects Agency (ARPA) sponsored Consortium on Wideband All-Optical Networks in developing architectures, technology components, and applications for the realization of scaleable, wideband, and transparent optical wavelength-division multiplexing (WDM) networks. Our architecture addresses all-optical transport over the wide, metropolitan, and local areas. It utilizes wavelength partitioning, routing, and active multiwavelength cross-connect switches to achieve a network that is scaleable in the number of users, data rates, and geographic span. The network supports two services which can be point-to-multipoint or multipoint-to-multipoint simplex or duplex connections. The A service is a transparent physically circuit-switched service and the B-service is a scheduled time-slotted circuit which is transparent within its time slots. We have developed a 20-channel local and metropolitan area WDM testbed deployed in the Boston area, now undergoing characterization and experimental applications.

Our goal is to devise a computer comprising large numbers of cooperating processors (LSI). In doing so we reject the sequential and memory cell semantics of the von Neumann model, and instead adopt the asynchronous and functional semantics of dataflow. We briefly describe the high-level dataflow programming language Id, as well as an initial design for a dataflow machine and the results of detailed deterministic simulation experiments on a part of that machine. For example, we show that a dataflow machine can automatically unfold the nested loops of n X n matrix multiply to reduce its time complexity from 0(n3) to 0(n) so long as sufficient processors and communication capacity is available. Similarly, quicksort executes with average 0(n) time demanding 0(n) processors. Also discussed are the use of processor and communication time complexity analysis and "flow analysis," as aids in understanding the behavior of the machine.