Brewster Roe Hemenway

The OSMOSIS Optical Packet Switch for Supercomputers: Enabling Technologies and Measured Performance

The OSMOSIS project explores the role of optics in large-scale interconnection networks for high-performance computing (HPC) systems. Its main objectives are solving the technical challenges to meet the stringent HPC requirements of high bandwidth, low latency, low error rates, and cost-effective scalability. We discuss the technologies and architectural innovations that enabled us to build a demonstration system meeting these targets. We demonstrate the optical performance for the 64 ports @ 40 Gb/s data paths across the semiconductor optical amplifier based optical crossbar, and report on the implementation of the electronic central controller.

Optimization of a supercomputer optical interconnect architecture

We present a novel, optimal architecture for a NxN supercomputer optical interconnect, composed of arrayed waveguide grating multiplexers/demultiplexers and a minimum total number, of the order of N In N, of semiconductor optical amplifiers used as on-off gates.

Interconnection of metropolitan and backbone networks

As Internet traffic continues to grow, eventually dominating voice traffic, the network economics and traffic granularities may become favorable for merging the metropolitan core with the long-distance backbone network, to form an integrated 10 Gb/s wavelength-routed network architecture.

Value proposition for configurable optical network elements

The value of configurable optical network elements for the fast provisioning of wavelength services is assessed against manual provisioning. Results are presented that were obtained by evaluating the long haul wavelength circuit provisioning process.

Influence of Transmission Impairments on the OSMOSIS HPC Optical Interconnect Architecture

We examine the impact of transmission impairments on the performance of the optical supercomputer interconnect architecture, initially proposed in the context of the optical shared memory supercomputer interconnect system (OSMOSIS) project. We study two versions of the aforementioned optical interconnect that differ in terms of the number of semiconductor optical amplifiers (SOAs) used as ON-OFF gates. For practical reasons related to packet arbitration, the size of the crossbar switch of the optical interconnect in this study is limited to 64 ports. The switch is based on a broadcast-and-select architecture and employs DWDM in conjunction with 10 Gb/s intensity modulation/direct detection per wavelength channel. We show, both by experiment and by simulation, that the minimization of the number of SOAs in the optical switch by taking advantage of the cyclic routing capability of optical arrayed waveguide multiplexers/demultiplexers leads to negligible performance deterioration compared to conventional wavelength-space switches that are prohibitive slower and do not use any inherent gain properties like in OSMOSIS.

Wavelength-space permutation switch with coherent PDM QPSK transmission for supercomputer optical interconnects

We experimentally study the performance of an economically-viable, high-capacity supercomputer optical interconnect employing wavelength-space optical packet switching, polarization division multiplexed (PDM) quadrature phase shift keying (QPSK) modulation and coherent detection.

Performance assessment of an optimized optical supercomputer interconnect architecture

We investigate the performance of an optimized optical supercomputer interconnect architecture using a minimum number of on-off gates. A 64×64 optical interconnection is demonstrated using 10 Gb/s IM/DD and 2.5 GBd coherent PDM/QPSK optical links.

Implementation Challenges in the OSMOSIS Optical HPC Switch

OSMOSIS is an optical packet-switching interconnection network for high-performance computing systems. It aims at delivering sustained high bandwidth, very low latency, and cost-effective scalability. We describe how we address the challenges in the implementation of its optical data path and electronic control logic

Differential signaling for low optical energy consumption in datacom optical interconnects

We propose the use of differential signaling based on parallel transmission of complementary M-ary PAM optical waveforms over fibers of approximately the same length, in conjunction with balanced direct detection, to reduce optical interconnect energy consumption.

Experimental demonstration of fast-response spectral power equalizer for reconfigurable WDM optical networks

A fast spectral power equalizer was designed and tested in a reconfigurable optical network testbed. Its response time is ~100 microseconds. Dynamic power fluctuation caused by add/drop switching in reconfigurable optical networks can be compensated by this technology.