ABSTRACT

              Design of a petaflops network computer 
           		Larry Wittie

In this talk, I will show two ways to build a bread-box-sized switching
network that can deliver 1 PetaByte/second in random access memory traffic.
This is the data equivalent of 1,000 Harvard University libraries per
second, or roughly all written material on earth delivered every second.

Rapid Single Flux Quantum (RSFQ) is a digital logic for superconducting
circuits. RSFQ has made computing at a petaflops (10^15 floating-point
operations per second) scale feasible within the next decade.  RSFQ logic
is fast: simple circuits already work at 700 GigaHertz.  However, the
major advantage of RSFQ technology for computers is not so much its
unparalleled speed, as its uniquely low power consumption: about 1/1000th
that of semiconductor logic.  An RFSQ computer 4 million times faster than 
your desktop PC needs only household current to run, not the multimegawatts
that an equally powerful semiconductor system would require.

This work is a part of a well-funded project to design a petaflops-scale
computer using a hybrid technology multi-threaded architecture (HTMT).
The superconductor core of the HTMT system will be a high-bandwidth
low-latency RSFQ cryoelectronic switching network (CNET) connecting 4,096
computing modules with each other and with 100,000,000 MegaBytes of
room-temperature semiconductor memories.