NIC Setting: Full or Half Duplex ??

[Synapse Syndrome]

One of the lights on my router/switch often turns red indicating that one of
my NICs is reverting to 10mbit speed. I want to change it from
Auto-negotiate to full speed, but do not know whether to use Full or Half
duplex. Which do I use? Searching on Google doesn't give any clear
answers.

Cheers

ss.

 

[Michael Bednarek]

One of the lights on my router/switch often turns red indicating that one of
my NICs is reverting to 10mbit speed. I want to change it from
Auto-negotiate to full speed, but do not know whether to use Full or Half
duplex. Which do I use? Searching on Google doesn't give any clear
answers.

It should be identical to the settings at the device connected to that
port, preferrably not Auto-negotiate at either end.

IMO full-duplex on a busy network is slower than half-duplex unless all
devices implement the same throttling/back pressure mechanism. YMMV.

 

[John Wunderlich]

One of the lights on my router/switch often turns red indicating
that one of my NICs is reverting to 10mbit speed. I want to
change it from Auto-negotiate to full speed, but do not know
whether to use Full or Half duplex. Which do I use? Searching on
Google doesn't give any clear answers.

It depends on what you're connecting to. Generally, a "hub" device
uses half-duplex. A "switch" or "router" device is usually full
duplex. A half-duplex setting expects to see everything it sends on
its receive line; if it does not, it concludes there's been a collision
and the packet is retransmitted. Full duplex has a dedicated buffered
receiver on the end of the transmit lines so it is expected that all
packets sent are transmitted correctly unless an error/retry packet is
sent back.

HTH,
John