[TUHS] OSI stack (Was: Posters)

Paul Winalski paul.winalski at gmail.com
Thu Feb 7 04:22:08 AEST 2019

On 2/6/19, Noel Chiappa <jnc at mercury.lcs.mit.edu> wrote:
>     > On Wed, Feb 06, 2019 at 10:16:24AM -0700, Warner Losh wrote:
>     > In many ways, it was a classic second system effect because they were
>     > trying to fix everything they thought was wrong with TCP/IP at the time
> I'm not sure this part is accurate: the two efforts were contemporaneous; and
> my impression was they were trying to design the next step in networking, based
> on _their own_ analysis of what was needed.

That's my recollection as well.  The OSI effort was dominated by the
European telcos, nearly all of which were government-run monopolies.
They were as much (if not more) interested in protecting their own
turf as in developing the next step in networking.  A lot of the
complexity came from the desire to be everything to everybody.  As is
often the case, the result was being nothing to nobody.

Phase V of DEC's networking product (DECnet) supported X.25 as an
alternative to DEC's proprietary transport/routing layer.  I had to
install this on one of our VAXen so we could test DECmail, our
forthcoming X.400 product.  I remember X.25 being excessively
complicated and a bear to set up compared to Phase IV DECnet (the
proprietary protocol stack).

-Paul W.

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