OID_802_11_RSSI vs OID_802_11_BSSID_LIST

Hello

I'm using these two objects "OID_802_11_RSSI" and "OID_802_11_BSSID_LIST" in order to read the received signal strength from my NIC (D-Link AirPlus DWLG650+)

When I use the first one (RSSI) I get the signal strength in dBm from the access point that I am connected with. This value is reasonable (-45dBm, -50dBm, -60dBm....). But when I use the second one (BSSID_LIST) I get the macs of each access point in the WiFi area correctly but the value of the received signal strength is impossible (120, 100, 90....). It is said in the OID specifications that the returned value is dBm but it is not possible to receive 120 dBm!!!

Reading some previous posts I've found one called "How to convert RSSI (dbm) to Percentage?" where it is said

>> There is a table to represent the dBm value of each vendor. Fo
>> example
>> RSSI = -70dBm is equivalent to RSSI = 20 in "Conversion for Symbol"

So I thought about the possibility of any conversion but the relationship between the signal strengh of both parameters is not linear..

Anyone can help me to find out what are the units of OID_802_11_BSSID_LIST->RSSI parameter

Thank you.

Benoît
Tue Mar 02 11:08:19 CST 2004

Pretty sure the value is from -200 (0%) to -10 (100%).


-----
Benoît Bousquet
(e-mail address is invalid)

"A. Arias" <anonymous@discussions.microsoft.com> wrote in message
news:5FB24C57-00A8-4A0C-A8A3-38A0220FAE7C@microsoft.com...
> Hello,
>
> I'm using these two objects "OID_802_11_RSSI" and
"OID_802_11_BSSID_LIST" in order to read the received signal strength from
my NIC (D-Link AirPlus DWLG650+).
>
> When I use the first one (RSSI) I get the signal strength in dBm from the
access point that I am connected with. This value is reasonable
(-45dBm, -50dBm, -60dBm....). But when I use the second one (BSSID_LIST) I
get the macs of each access point in the WiFi area correctly but the value
of the received signal strength is impossible (120, 100, 90....). It is said
in the OID specifications that the returned value is dBm but it is not
possible to receive 120 dBm!!!!
>
> Reading some previous posts I've found one called "How to convert RSSI
(dbm) to Percentage?" where it is said:
>
> >> There is a table to represent the dBm value of each vendor. For
> >> example:
> >> RSSI = -70dBm is equivalent to RSSI = 20 in "Conversion for Symbol".
>
> So I thought about the possibility of any conversion but the relationship
between the signal strengh of both parameters is not linear...
>
> Anyone can help me to find out what are the units of
OID_802_11_BSSID_LIST->RSSI parameter?
>
> Thank you.

Thomas
Tue Mar 02 12:43:45 CST 2004

Is it possible that you have some sort of structure alignment problem? I
have seen differences in RSSI values between OID_802_11_RSSI and
OID_802_11_BSSID_LIST, but never impossible results.

If you are running on XP you could try the PCAUSA OIDScope. It has an 802.11
Property Page that displays OID_802_11_RSSI and OID_802_11_BSSID_LIST. If
OIDScope does not show impossible values, then you have a structure packing
or other simple structure access problem. If OIDScope also shows bogus
values, then the adapter or miniport is probably bozo.

OIDScope can be downloaded from:

http://www.pcausa.com/Utilities/ndistools.htm

Good luck,

Thomas F. Divine

"A. Arias" <anonymous@discussions.microsoft.com> wrote in message
news:5FB24C57-00A8-4A0C-A8A3-38A0220FAE7C@microsoft.com...
> Hello,
>
> I'm using these two objects "OID_802_11_RSSI" and
"OID_802_11_BSSID_LIST" in order to read the received signal strength from
my NIC (D-Link AirPlus DWLG650+).
>
> When I use the first one (RSSI) I get the signal strength in dBm from the
access point that I am connected with. This value is reasonable
(-45dBm, -50dBm, -60dBm....). But when I use the second one (BSSID_LIST) I
get the macs of each access point in the WiFi area correctly but the value
of the received signal strength is impossible (120, 100, 90....). It is said
in the OID specifications that the returned value is dBm but it is not
possible to receive 120 dBm!!!!
>
> Reading some previous posts I've found one called "How to convert RSSI
(dbm) to Percentage?" where it is said:
>
> >> There is a table to represent the dBm value of each vendor. For
> >> example:
> >> RSSI = -70dBm is equivalent to RSSI = 20 in "Conversion for Symbol".
>
> So I thought about the possibility of any conversion but the relationship
between the signal strengh of both parameters is not linear...
>
> Anyone can help me to find out what are the units of
OID_802_11_BSSID_LIST->RSSI parameter?
>
> Thank you.

Igor
Tue Mar 02 17:52:19 CST 2004

The 802.11 NIC driver can return either NDIS_WLAN_BSSID structure or
NDIS_WLAN_BSSID_EX. Make sure you check Length field correctly.

"Thomas F. Divine [DDK MVP]" <tdivine@NOpcausaSPAM.com> wrote in message
news:O24ZMYIAEHA.3220@TK2MSFTNGP10.phx.gbl...
> Is it possible that you have some sort of structure alignment problem? I
> have seen differences in RSSI values between OID_802_11_RSSI and
> OID_802_11_BSSID_LIST, but never impossible results.
>