Reed's views, was [e2e] Cannara's views

Cannara cannara at
Sat Apr 14 22:54:46 PDT 2001

David, just a few comments on the pedantry front, since we're now into oracle
mode for the young ones...

"David P. Reed" wrote:
> I changed the subject line because this has nothing to do with Outer Space.
> For the students and others that might actually find Cannara's views
> plausible, let me offer another clear point of view.
> There are two things that Cannara says over and over.
> 1) The current internet protocol doesn't "optimize" the use of new
> technologies (or incorporate those theoretical results that are closely
> tied to the special properties of those cool new things).
> 2) New phenomena weren't anticipated in the original design.
> (1) is true.  The current internet protocol NEVER "optimized" the use of
> any technology.  So what?  That was part of the design philosophy.  In
> order to be flexible enough to incorporate heterogeneity and change, you
> can't optimize for a particular technology.  More importantly, if you do,
> you die at the next change.

...Au contraire, TCP/IP was optimized for small MTU, 56kb/s, byte-oriented
transfers, implemented on 16-bit machines that could do 32-bit (double-word)
ops.  In other words, Telnet, RPC, FTP, etc.  TCP still counts bytes in
sequence #s.  When all 3GBytes of Beethoven's symphonies can be ATMed in
19sec, or OC48'd in 1 second, having a transport getting fooled by false
congestion positives and dropping out for a second or so doesn't really make
sense, no matter how many times we click our slippers and say: "I didn't
optimize", "I didn't optimize"...
> (2) is wholly false.  The original design philosophy was based on a
> principle of humility - we KNEW we couldn't ever anticipate new apps or
> patterns of use.  At the time, computer-computer connections over LANs were
> thought to be important.  I had designed a protocol to "optimize" what we
> thought might happen in those environments (as had PARC, with PUP).  Rather
> than "fork" the design to pursue our own egotistical desires to demonstrate
> genius in a narrow subset of networking, both groups ended up supporting
> the incorporation of a couple of the important insights into a
> far-from-optimal Internetworking approach.  And guess what?  It paid off.

..."Wholly false" -- so all new technology was anticipated, but ignored?  Why,
because clairvoyance was assigned no value?  What do you know of the future
now that you're not telling us and that networking can safely ignore?  I can't
imagine this is what you mean by "wholly false".  It's interesting that a
networking system that, for instance, couldn't anticipate needing more than 32
bits for addressing all those machines the future held, when Xerox already had
implemented 80 in XNS, is somehow bestowing a "pay off".  It certainly has
paid off for all who make products and money plugging the holes and working
around the 'features' of TCP/IP these days.



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