Date: Sat, 23 Apr 2005 00:52:50 -0400
To: WSFA members <WSFAlist at WSFA.org>
From: "Mike B." <omni at omniphile.com>
Subject: [WSFA] Re: Net History (was Re: Quoting)
Reply-To: WSFA members <WSFAlist at WSFA.org>

At 12:19 AM 4/23/05 -0400, Steve Smith wrote:

>Originally, ARPANet and later the Internet was just one more network.
>There were lots of others -- Compuserve, Tymenet, Genie, The Well, and,
>of course, AOL.  Not to mention about a zillion PC BBSs.  Each had its
>own standard for mail, news, and so forth.  Problem was, they couldn't
>communicate with each other.

Mostly right.  I ran a FidoNet BBS in the late 80s.  At the time I worked
at Goddard SFC on one of the main routine nodes for the DECnet-based SPAN
network.  Just to see if it was possible, I sent myself an e-mail from home
at lunchtime, to my work account.  It took almost 2 hours to get there, but
it worked.

I had to send it over FidoNet (a store and forward sort of thing using
modems on MS-DOS PCs mostly) to the system in the local net that was the
gateway to Usenet (The Black Cat's Shack...don't recall the node number but
it was net 109).  That system sent it to the Arpanet gateway.  That system
sent it over Arpanet to the SPAN gateway (which I think was at JPL), which
then sent it over SPAN to my work account at Goddard.  This involved a very
arcane "mail to:" address, as it was before DNS so the routing was part of
the address and it involved three different mail protocols...FidoNet,
Arpanet and DECnet's.

>a nuclear war, but the design is certainly robust.)  The others were all
>modeled on a central server that controlled everything.

The commercial ones like Compuserve and Genie were, but FidoNet was fairly
distributed and DECnet is too.

FidoNet had BBSs grouped into "nets" based on who was a local call to whom.
 Each net had a gateway to a regional concentrator or a "backbone" system
that was willing to take on the long distance charges needed to move data
between local calling areas.  Some of these had WATTs lines and some just
didn't mind a lot of long distance charges and some took advantage of deals
like Sprint offered where calling at particular times got you really low
rates (usually the middle of the night).  Every node in the world had info
on every other (updated weekly), so it was possible to send directly to the
destination system if you wanted to pay the costs, otherwise you sent to
the gateway system and rode free.  FidoNet had over 10,000 nodes in it when
I shut down mine.

DECnet uses "routers" and "end nodes".  "End nodes" only know how to talk
to routers in their network (usually local systems).  Routers are either
level one or level two.  Level one routers can talk to any system in the
local network, while level two routers can talk to any local system or to
systems in other networks.  It's mostly a matter of how big a database they
maintain and who they update with changes...along with what forms of
hardware connectivity they have.  You can have the same sort of redundant
routes that the internet has, and weight them according to usage preference
(i.e. make the faster or cheaper one preferable so the slower or more
expensive one only gets used when the other is saturated or down).  SPAN
was one of the larger DECnet networks with over 8000 nodes.  DEC had a much
bigger one internally, which maxed out the 65,000 system limit and resulted
in DECnet Phase V, which had larger limits.
;-)

As to exploding computers on TV, I keep wondering when in the period
between now and Star Trek's time the human race forgot all about how to
build relays and other forms of remote power switching along with circuit
breakers and fuses so that overloads in high power equipment (like phasers
and warp engines) don't result in electrocuted console operators and
showers of sparks on the bridge.  Heck, my *motorcycle* uses that stuff to
avoid running heavy starter cables up to the handlebars and back to control
the starter motor, along with the attendant risk to the rider working the
switch in possibly wet conditions of having a couple dozen amps at 12 volts
under his thumb, so I just wonder why a *starship* can't do that?

-- Mike B.
--
"The right to buy weapons is the right to be free."
    -- A.E. Van Vogt, "The Weapon Shops Of Isher", ASF December 1942