[HECnet] Maximum number of L2 routers?

[Clement T. Cole]

Unix certainly could   bridge and route with 4.1a after Sam wrote the routed stuff which he will tell you was ripped off from a Xerox routing protocol.     My memory is hazy here.   I think he started that work with BBN stack which a couple of us ran on 4.1 before joy created sockets.     I have memories of debugging that with Eric cooper and Sam because they were in Evans and I ran the link in Cory in the CAD group at the time as one of our 3 780s was on both the Cory LAN and the other end of a link to Evans [3meg Ethernet not even 3com or interlan he in those days]. My memory is that the other end of that Evans link was the system KIM which was on the Evans internal LAN and the link between the buildings.

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On Feb 28, 2015, at 3:24 PM, Cory Smelosky <b4 at gewt.net> wrote:

On Sat, 28 Feb 2015, Johnny Billquist wrote:

Not sure what you mean with a star configuration. The first (proprietary) glass fiber repeaters were star designs, was that what you meant?

Not all ethernet segments have to be in one line. But since the maximum number of repeaters between any two nodes were two, you could (obviously) have repeaters in configurations that just made sure not more than two were involved in any given path, but there could be more than two totally.
The simplest such configuration would be a star.


How are you doing more than one line without bridges or repeaters? Have I misread?

(Not counting routing)

But my memory is fuzzy enough at this point that I should probably go read the docs instead of continuing to ramble here...

DEC also sold remote bridges and repeaters. A glass fiber trunc connected either two remote repeaters or bridges or one of each. I forgot how long a fiber segment could be, 2500 m IIRC. That gave you some room to plan on a large site. Two remote repeaters counted as one in the two repeater rule.
Expensive stuff though. A Lanbridge 100 was 30.000 guilders in 1988. A remote bridge was even more expensive.

Yeah.

But the ethernet was older than those devices. If my memory serves me right, the original repeater (from DEC) was the DEREP. Probably even more expensive back in the day. :-) And there were no bridges back then.


Hmmmm, when did VMS/BSD get software bridging capabilities?

    Johnny


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Cory Smelosky
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