Subject: Re: Dumb question time...
To: None <>
From: Arno Griffioen <>
List: port-vax
Date: 06/17/1998 13:43:58
>      What is an Ethernet driver supposed to do with a bad received packet? 
>      Drop it on the floor? Pass it along anyway? Return 0? -1? the number 

Usually it throws the packet away and signals the higher level that a
receive error occured. The higher protocols should take care of

I'm just wonrdering, because in my experience it's pretty uncommon
to see RX errors on ethernet. 

The only times I saw them were when stuff was broken (cables, hubs, etc)
so the data got (partially) mangled. 

Ethernet cards should sort out collission-retransmit themselves, with
data intact.

Could you give any indication as to the type of error it reports?
Framing errors? Overruns? Carrier loss? Excessive collissions? 

Overrun would be caused by the machine reading the packets too slowly
from the buffer, but I thought VAXstations used LANCE chips and
those either doe DMA to memory or to a dual-port buffer. 
(correct me if I'm wrong)

Framing errors would cause me to take a good hard look at the
wiring and components (not forgetting transceivers!!).

Hope this helps a bit.

							Bye Arno.

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