From mboxrd@z Thu Jan 1 00:00:00 1970 From: b4@gewt.net (Cory Smelosky) Date: Wed, 26 Nov 2014 01:48:27 -0500 Subject: [TUHS] BerkNet In-Reply-To: <14353.1416983329@cesium.clock.org> References: <14353.1416983329@cesium.clock.org> Message-ID: <65EA978B-BD50-4694-89A7-3711F5F8555B@gewt.net> Sent from my iPhone > On Nov 26, 2014, at 01:28, Erik E. Fair wrote: > > Date: Fri, 21 Nov 2014 01:07:59 -0500 (EST) > From: Cory Smelosky > > 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