which Wifi cards can be used for a WAP?

Sam Leffler sam at errno.com
Sat Apr 2 14:04:35 PST 2005


Joerg Sonnenberger wrote:
> On Sat, Apr 02, 2005 at 12:16:35PM -0500, Brian Reichert wrote:
> 
>>In perusing many of these cards specs, I see many of them offer a
>>'turbo mode' of 108 Mbps.
> 
> 
> That's a vendor-specific mode. I strongly advice you _against_ using it,
> it's using at least one additional channel and only adds speed for very
> short distances. If you follow the common recommendation of leaving one
> channel before and after the active channel, you end up using at least
> 5 channels for turbo mode compared to three for normal, it's not worth
> the trouble.

This is misleading.  First turbo mode can only be used in the 2.4G band 
on channel 6 and does not impact operation on channels 1 and 11.  Any 
channels in between already suffer from normal (i.e. non-turbo) use 
because the channel spread in the 2.4 band means traffic is visible if 
you use the in-between channels.  Further, turbo mode (as part of 
SuperG) requires that the AP detect non-turbo capable stations and 
disable turbo use when such stations are present.

As to whether or not to use it; I said in another note that it's really 
most useful in the 5Ghz band where there's more available spectrum and 
channel spread eliminates any possible interference.

	Sam


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