[TUHS] BerkNet

Cory Smelosky b4 at gewt.net
Wed Nov 26 16:48:27 AEST 2014

Sent from my iPhone

> On Nov 26, 2014, at 01:28, Erik E. Fair <fair-tuhs at netbsd.org> wrote:
>    Date: Fri, 21 Nov 2014 01:07:59 -0500 (EST)
>    From: Cory Smelosky <b4 at gewt.net>
>    I take it you actually understand BERKNET's addressing then? I could 
>    never figure it out!
> BerkNET was its own thing: it was effectively a store & forward batch/file
> based networking system which could handle E-mail, print jobs, and remote
> execution of commands for your account on another machine, if you sent the
> password to the account along. It's somewhat similar to UUCP, actually. Eric
> Schmidt (of Sun, Novell, & Google) wrote the code as a UCB grad student,
> because (as I heard it) the Berkeley Computer Center wanted to be paid money
> every time an operator had to hang a magtape on a tape drive, and the CS
> department was tired of being bled to move small files around.

That explains that!

> BerkNet used one single ASCII character designation per machine, originally
> just 26 allowed, and later extended to numerals for a total of 36 (before
> Ethernet & TCP/IP obsoleted it). The routing table for BerkNet was a
> statically-compiled table in every instance of its primary daemon, and if the
> network topology changed sufficiently, each daemon had to be modified and
> recompiled. No redundancy allowed in the network, if I recall correctly.

Heh, looks like I won't bother with Berknet then. ;)

> Pretty slow convergence for changes to the routing table.

To say the least!

> Longer names were also allowed as aliases for the single letter, and that's
> what was sent to the rest of the world in E-mail addresses, e.g.
> cory:cc-54 at berkeley (Computer Club account #54, on the Cory Hall PDP-11/70;
> I think Cory's letter was "y") was my first ARPANET-reachable E-mail address.
> There might be some instances of that in the HUMAN-NETS or SF-LOVERS archives
> from 1981. I suspect that BerkNet's colon separator for host:file was how
> the rcp command got that syntax, and probably how ssh inherited it.
> Google turned up the following: http://typewritten.org/Articles/berk-net.html
> Being RS-232 serial-based, the interrupt loading was horrific ... so they
> restricted the bandwidth to 1200 baud (plus, there were some rather long RS-232
> cable runs between buildings), unless you used a serial interface card that
> had some input buffering & DMA I/O like the DH-11. The DZ-11 was
> contraindicated. To further lower overhead, there's even a TTY line discipline
> for BerkNet, so you don't wake up the daemon until a full packet arrives, even
> though the TTY interface is set to "raw" mode.
> I was for a time a system administrator for the "x" machine at UCB: the Onyx
> Z8002 installed for the undergrads in the basement of Evans Hall (room B50).
> That's also the machine on which "B news" was written by Matt Glickman.

What OS did that machine run? I don't think BSD unless it was elsewhere in the tree.

> Later, I ran a small BerkNet (before we got Ethernet) at Dual Systems in
> Berkeley, between the Dual 83/80 mc68000-based S-100 systems in the various
> departments (engineering, sales, manufacturing/test), before we got an S-100
> Ethernet card working and ran thick Ethernet. We were able to run it at 19,200
> baud because Dual made some really sweet, 256-byte input buffer, DMA I/O,
> 4-port serial cards: the SIO-4/DMA, based around the Zilog z8530 DUART.

I'd love a 68k S-100 system.

> I insisted that we wait for ARP to be done before we deployed Ethernet &
> TCP/IP, because evil old hack of grabbing a Class A IP network number,
> pretending that the first three MAC address bytes were always the same (after
> all, everyone always uses Ethernet interfaces from the exact same manufacturer
> in every host on a given LAN, right?) and mapping the last three MAC bytes
> into the host part of the Class A wasn't going to fly in the real world.

Yeah...that would not have worked well. ;)

> The hacks we used to do to make these turkeys fly ...
>    Erik <fair at netbsd.org>

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