Vintage Computer Festival <vcf(a)siconic.com> wrote:
On 8 Jul 2003, Frank McConnell wrote:
I just get something of a chuckle out of people
who figure all
Ethernet cards are alike. Perhaps they have forgotten the lessons of
the 3Com 3C50[01].
What lesson was that? I thought they were fine. At least I never had
problems with them.
I am pleased to be able to say that I no longer remember the details,
but the problem was something like that the card had enough room in
its buffer to hold no more than one received packet. If you sent it
another one before the processor on its end got around to reading the
packet out of it, one packet or the other got dropped (I'm thinking
the one in the buffer got dropped so that the new one could be
buffered).
If you didn't want any packets to get dropped, you needed to be careful
to not overrun the buffer by having more than one packet outstanding.
Keep in mind that this was 1987 or so and PC clock speeds were right
around Ethernet bus speed, so the PC couldn't get the packets out of
the buffer as quickly as the network could put them there.
If someone else out there remembers more, please do feel free to jump in.
-Frank McConnell