The spec for RSSI is very loose - RSSI is just a 8 bit unsigned number, guaranteed to be a monotonically increasing function of signal strength. You don't get to know anything about the scale, or linearity of the function. In essence RSSI is a vendor specific value, of no known units. Not very useful unless you know some card specific details to help interpret it.
Now some cards return a signal strength in dBm as the RSSI - note that this fits the requirements of a RSSI measure just fine. RCPI is simply a more tightly specified signal strength measure. Just saying that a RSSI value is not very useful. Simon -----Original Message----- From: Johannes Berg [mailto:[EMAIL PROTECTED] Sent: Thursday, August 17, 2006 12:20 AM To: Simon Barber Cc: Dan Williams; netdev@vger.kernel.org; Jean Tourrilhes Subject: RE: proposal for new wireless configuration API On Wed, 2006-08-16 at 11:02 -0700, Simon Barber wrote: > I'd suggest that the new signal strength measure should be defined as > 'RCPI' - the 'Received Channel Power Indicator' - which is defined in > IEEE 802.11k (the Radio Measurements amendment to 802.11). Except that we unfortunately have no way of getting this with all the reverse engineered devices :) Hence, I guess we should then have multiple different possibilities. A device reporting RCPI would be better than just reporting RSSI, but that's still better than nothing... johannes - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
