.From: Tony Duell <ard_at_p850ug1.demon.co.uk>
.
>> I've only found one place where it's a problem so far, with an NE2000
card
>> in a slow XT compatible the data rate (even at 10 Mbps) was too high
for it
DMA, a must and a lot of packet buffers (ramdisk).
>I would be suprised if a PDP11 or PERQ or D-machine or... would manage
>anything close to 100Mbps. In fact I know it won't.
PDP-11 (q or unibus) will not. 100mb/S rate needs a minimum of
12.5mb second sustained transfer and burst rates slightly higher.
None of the ISA-8/16 bit systems can.
>Of course another issue is that some of these machines have built-in
>ethernet interfaces (PERQs do, for example), and there's no way of
adding
>a 100Mbps card to them.
Fortunately 10mb/s is still around for a while.
>> Hubs and switches are getting cheap and small. An 8 port switch is
about the
>
>What's the cost got to do with finding space for it, finding power for
>it, or maintaining it?
It's wall wart powered but software maintenance for them can be a pain.
Not much bigger than a unmanaged hub. There is little value in switches
until you get more than 4-5 systems that want to carry intense
conversations
concurrently.
>> AUI tranciever in a junk bin, but I've never seen 10BaseT-coax
converter
the net at work uses a few of them, those are just baluns. Also the
10bt to AUIs are handy for boosting signal. They seem better at taking
a noisy 10bt and pumping it on the backbone (thinnet) than a simple
unmanaged hub.
>Got a load of assorted transceivers for 10 p each recently (about 15
>cents to you...).
They can be found cheap, used.
Allison
Received on Wed Nov 22 2000 - 20:50:26 GMT