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∂AIL Mr. Joel Trimble↓Sensor and Control Technology Division
↓Office of Naval Research↓800 South Quincy St↓Arlington, VA 22217∞

Dear Mr. Trimble:

	Lowell Wood has asked me to write you giving my opinion
of the S-1 computer project.
   
	I have followed this project since its inception.
Initially I was skeptical about whether the group could design a
large computer, but now it is clear that they can and that the
computer is likely to work.  Whether it will be as fast as they
expect still remains to be seen, but I see no reason at present
for more than the usual worry about any computer design.

	Ever since the architecture became firm, I have been enthusiastic
about it, because it is the first large computer architecture to
solve two important problems:

	1. It has a large enough address for the next fifteen years.
The D.E.C. PDP-10, which we use in our laboratory, is nearing the
end of its utility for lack of address, and for many reasons, the
IBM 370 architecture is not a satisfactory successor.

	2. The S-1 embodies the most plausible approach to getting
efficient computation from a multi-processor computer.  Namely, each
processor has its own control unit, each processor addresses the whole of
memory, and tasks that can be done in parallel are put on queues and then
done by whatever processors become free.  I have long been convinced that
such a multi-processor computer can be programmed to use all processors
efficiently on large problems with little more difficulty than programming
a single processor, with only minor additions to present programming
languages, and often with only minor changes to present programs.
We also believe that this machine organization is suitable for general
time-sharing use.

	I anticipate that the S-1 project will succeed, and if it does,
we would hope to acquire a system for our Laboratory and for the
Stanford University Computer Science Department.

.sgn