Strange situation with a NetGear PCI 10/100 tulip based card.  It
appears to receive its own ARP broadcast instead of the response from
the target machine.  Before pointing the finger at tulip, has anybody
seen this symptom on any other network card?  Does it ever make sense
for a card to receive its own broadcasts?

Three machines on a 10Mb hub.

A Another box, Linux
B Bad card, Linux 2.0.36
C Cisco router

B issues ARP for C but never sees a response.  Monitoring the LAN from
A, the ARP request and response are both good - rules out the cable,
hub and collisions.  B "receives" a packet but a dump of the "incoming"
packet in tulip.c shows it is identical to the outgoing broadcast
request.  Not surprisingly, B discards it.

To complicate the issue, if A pings B, the ARP broadcast "where is B,
tell A" is received correctly by B, it fills in its ARP table and runs
fine.  So B correctly receives other broadcasts and, once its ARP cache
is filled, it has no problem with *any* unicast packets.  Manually
setting C's address in B's ARP cache avoids the initial broadcast and B
and C communicate via unicast with no problems.

The problem only occurs when B sends a broadcast, it receives its own
broadcast instead of the real response.  This appears to be related to
the load on the network.  If the network is "quiet" then sometimes B
will get the real response instead of its own transmission.

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