Since folks are debating whether 21 bits is really enough for Unicode
forever, I thought I should toss in these gems from my quotation
collection, about previous mistakes when people thought something was
big enough:
\QUOTATION{
There is only one mistake that can be made in computer design that is
difficult to recover from---not having enough address bits for memory
addressing and memory management. The PDP-11 followed the unbroken
tradition of nearly every computer.
}{
C. G. Bell and W. D. Strecker\\
1976 % Hennessy and Patterson p. 481
}
\QUOTATION{
A partial list of successful machines that eventually starved to death
for lack of address bits includes the PDP-8, PDP-10, PDP-11, Intel
8080, Intel 8086, Intel 80186, Intel 80286, AMI 6502, Zilog Z80,
CRAY-1, and CRAY X-MP.
}{
David A. Patterson and John L. Hennessy\\
1990 % p. 481
}
\QUOTATION{
Pitfall: Extending an address space by adding segments on top of a
flat address space.\\[1ex]
\ldots{} From the point of view of marketing, adding segments solves
the problems of addressing. Unfortunately, there is trouble any time
a programming language wants an address that is larger than one
segment, such as indices of large arrays, unrestricted pointers, or
reference parameters. \ldots{} In the 1990s, 32-bit addresses will be
exhausted, and it will be interesting to see if history will repeat
itself on the consequences of going to larger flat addresses versus
adding segments.
}{
John L. Hennessy and David A. Patterson\\
1990 % p. 483
}
I haven't a similar quote about 32-bit IP addresses, but IPv6 (see RFC
1883) notes `` IPv6 increases the IP address size from 32 bits to 128
bits, to support more levels of addressing hierarchy, a much greater
number of addressable nodes, and simpler auto-configuration of
addresses.''
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