Darren.Reed at Sun.COM wrote:
> Garrett D'Amore wrote:
>
>> ...
>> This just doesn't make sense to me.
>>
>> A bunch of the properties above (powermode, radio, channel) are
>> really wifi-only properties.
>
>
> Does "powermode" relate to whether the NIC is on or off?
> Or is this something else, like signal strength?
Powermode relates to what the WLAN nic does when no traffic is present
for it. After a short time, it goes into a kind of sleep mode, and is
brought out of the sleep mode by checking with the AP periodically for
"updates".
Its totally a WiFi specific detail... intended to allow stations that
are mostly idle power down their radios most of the time.
>
> Some time ago there was some internal discussion about
> how to detect when you could turn off NICs mounted on
> the motherboard to save power (every little bit counts.)
Yes. A nic that is not plumbed, for example, should be able to be
powered off. (But mostly in the idle state, MAC chips don't consume
much power. Cassini may be an exception to this rule; probably other
10Gb MACs as well.)
What is more interesting, is the idea of negotiating for a slower speed
when the traffic load is very light, but as traffic increases then
renegotiating for a higher speed link. It takes about 1W for a gigabit
transceiver to run at GigE speeds. Its far far less than that at
100Mbps or 10Mbps speeds. Such an adaptive approach could probably save
a lot of power on laptops with onboard gigE, where every watt counts.
-- Garrett
>
> Darren
>
