This paper describes several high performance computing testbeds being developed for Ballistic Missile Defense Organization applications that are based on high speed wavelength division multiplexed (WDM) fiber optic packet network technology. By combining high speed (> 100 Gb/s per channel), low latency (< 1 us), and scalability, these WDM networks offer the possibility of creating very closely coupled meta-supercomputers for real-time theater defense applications. The testbeds consist of: (1) coarse grain architecture consisting of a few large massively parallel processor supercomputers connected by striped WDM trunks, (2) fine grain architecture consisting of clusters of workstations connected by a fast WDM packet network, and (3) a hybrid satellite/WDM fiber network for global grid. These all-optic networks are expected to enable a number of distributed teraflop applications, such as real- time image fusion, real-time radar signature analysis and modeling, very large scale simulation, and realistic synthetic scene generation. This paper describes these testbeds in more detail and their specific WDM component requirements.
Wafer and chip stacking are envisioned as means of providing increased processing power within the small confines of a three-dimensional structure. Optoelectronic devices can play an important role in these dense 3-D processing electronic packages in two ways. In pure electronic processing, optoelectronics can provide a method for increasing the number of input/output communication channels within the layers of the 3-D chip stack. Non-free space communication links allow the density of highly parallel input/output ports to increase dramatically over typical edge bus connections. In hybrid processors, where electronics and optics play a role in defining the computational algorithm, free space communication links are typically utilized for, among other reasons, the increased network link complexity which can be achieved. Free space optical interconnections provide bandwidths and interconnection complexity unobtainable in pure electrical interconnections. Stacked 3-D architectures can provide the electronics real estate and structure to deal with the increased bandwidth and global information provided by free space optical communications. This paper will provide definitions and examples of 3-D stacked architectures in optoelectronics processors. The benefits and issues of these technologies will be discussed.
This paper describes a new interconnect and local area network transmission concept for computer communications based on spectrally encoding one or more computer words into a wavelength datagram. At physical and data link level, this system resembles an optical ribbon cable, except that all the bits pass on one fiber optic waveguide. At the network level, such fiber optic link segments can be interconnected all-optically using 2x2 optical switches into ShuffleNet or other architectures that permit a photonic packet to pass from source to destination without being incumbered with the extra delay and bandlimiting associated with electronic switching and regeneration. Unique properties of such a system include low latency (<10ns), very high bandwidth (<100Gbit/s per port), precise time alignment (<10ps) of the individual word bits over km distances, and dynamic scalability to support cluster computing and distributed supercomputing. Novel system elements disclosed in this paper include: (J) a bit parallel wavelength (BPW) fiber optic link that uniquely maintains wavelength channel time alignment, (2) an innovative parallel stepped wavelength optical transmitter that time synchronizes each laser diode element at its optical output, (3) a spectral encoder/decoder that adds fault tolerance and optical message addressing capability, and (4) a technique for transmitting and maintaining time aligned multi-X solitons as parallel bits through fiber media. Applications to teraflop high performance parallel computing and DoD input/output (I/O) bound applications are described.