2.2.2.8.1 BssDesc Item
Each BssDesc item has the following packet format.
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1 |
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2 |
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3 |
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Length |
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BSSID |
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Channel |
Reserved |
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Frequency |
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SSID_Length |
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SSID (variable) |
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... |
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RSSI |
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BSS_Type |
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Phy_Type |
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IE_Length |
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IE_Data (variable) |
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Padding (variable) |
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Length (4 bytes): A 32-bit unsigned integer that specifies the size of this BssDesc item. This value MUST be a multiple of 4.
BSSID (6 bytes): The BSSID of the wireless network to which this BssDesc item refers.
Channel (1 byte): The channel used by the wireless network.
Reserved (1 byte): A value that MUST be zero and MUST be ignored on receipt.
Frequency (4 bytes): The frequency of the center channel for the wireless network, in kilohertz (kHz) units.
SSID_Length (4 bytes): A 32-bit unsigned integer that specifies the length in octets of the SSID field. This value MUST be greater than zero and less than or equal to0x00000020.
SSID (variable): The SSID of the BSS of the wireless network. The maximum length of this field is 32 octets.
RSSI (4 bytes): A 32-bit signed integer that identifies the RSSI of the IEEE 802.11 network [IEEE802.11-2007], in dBm. The normal range for an RSSI value is -10 dBm through -200 dBm.
BSS_Type (4 bytes): A 32-bit unsigned integer that specifies the wireless network connection method.
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Value
Meaning
0x00000000
Unknown mode.
0x00000001
802.11 infrastructure mode [IEEE802.11-2007].
0x00000002
802.11 IBSS or ad-hoc mode [IEEE802.11-2007].
Phy_Type (4 bytes): A 32-bit unsigned integer that specifies the wireless band used by the wireless network. Possible values are shown in the following table:
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Value
Meaning
0x00000000
Unknown wireless band.
0x00000001
802.11b [IEEE802.11-2007]
0x00000002
802.11g [IEEE802.11-2007]
0x00000003
802.11a [IEEE802.11-2007]
IE_Length (4 bytes): A 32-bit unsigned integer that identifies the size in octets of the IE_Data field.
IE_Data (variable): The 802.11 Information Elements data blob associated with the wireless network [IEEE802.11-2007].
Padding (variable): An optional field that, if exists, MUST be zero and MUST be ignored on receipt. The size of the field can be anywhere from 0 through 3 bytes. It exists to satisfy the requirement of the Length field.