wlanctl —
examine IEEE 802.11 wireless LAN client/peer table
  
    | wlanctl | [ -p] interface [...] | 
Use the wlanctl utility to print node tables from IEEE
  802.11 interfaces. Use the -a flag to print the nodes
  for all interfaces, or list one or more 802.11 interfaces to select their
  tables for examination. The -p flag causes only nodes
  that do not have encryption enabled to be printed. For example, to examine the
  node tables for atw0, use:
wlanctl may print this node table, for
    example:
atw0: mac 00:02:6f:20:f6:2e bss 02:02:6f:20:f6:2e
	node flags 0001<bss>
	ess <netbsd>
	chan 11 freq 2462MHz flags 00a0<cck,2.4GHz>
	capabilities 0022<ibss,short preamble>
	beacon-interval 100 TU tsft 18425852102545544165 us
	rates [1.0] 2.0 5.5 11.0
	assoc-id 0 assoc-failed 0 inactivity 0s
	rssi 161 txseq 10 rxseq 1420
atw0: mac 00:02:2d:2e:3c:f4 bss 02:02:6f:20:f6:2e
	node flags 0000
	ess <netbsd>
	chan 11 freq 2462MHz flags 00a0<cck,2.4GHz>
	capabilities 0002<ibss>
	beacon-interval 100 TU tsft 18425852105450086784 us
	rates [1.0] 2.0 5.5 11.0
	assoc-id 0 assoc-failed 0 inactivity 0s
	rssi 159 txseq 2 rxseq 551
atw0: mac 00:02:6f:20:f6:2e bss 02:02:6f:20:f6:2e
	node flags 0000
	ess <netbsd>
	chan 11 freq 2462MHz flags 00a0<cck,2.4GHz>
	capabilities 0022<ibss,short preamble>
	beacon-interval 100 TU tsft 18425852102558548069 us
	rates [1.0] 2.0 5.5 6.0 9.0 11.0 12.0 18.0 24.0 36.0 48.0 54.0
	assoc-id 0 assoc-failed 0 inactivity 145s
	rssi 163 txseq 9 rxseq 2563
 
This example is taken from a network consisting of three stations
    running in ad hoc mode. The key for interpreting the node print-outs
    follows:
  - mac
- In the example node table, the first network node has MAC number
      00:02:6f:20:f6:2e.
- bss
- The first node belongs to the 802.11 network identified by Basic Service
      Set Identifier (BSSID) 02:02:6f:20:f6:2e.
- node flags
- Only three node flags, “bss”, “sta”, and
      “scan”, are presently defined. The first node is
      distinguished from the rest by its node flags: flag “bss”
      indicates that the node represents the 802.11 network that the interface
      has joined or created. The MAC number for the node is the same as the MAC
      number for the interface.
- ess
- the name of the (Extended) Service Set we have joined. This is the same as
      the network name set by
      ifconfig(8) with the
      “ssid” option.
- chan
- wlanctlprints the channel number, the center
      frequency in megahertz, and the channel flags. The channel flags indicate
      the frequency band (“2.4GHz” or “5GHz”),
      modulation (“cck”, “gfsk”,
      “ofdm”, “turbo”, and “dynamic
      cck-ofdm”), and operation constraints (“passive
      scan”). Common combinations of band and modulation are these:- 
      - 
        | Band | Modulation | Description |  - 
        | 2.4GHz | cck | 11Mb/s DSSS 802.11b |  - 
        | 2.4GHz | gfsk | 1-2Mb/s FHSS 802.11 |  - 
        | 2.4GHz | ofdm | 54Mb/s 802.11g |  - 
        | 2.4GHz | dynamic cck-ofdm | mixed 802.11b/g network |  - 
        | 5GHz | ofdm | 54Mb/s 802.11a |  - 
        | 5GHz | turbo | 108Mb/s 802.11a |  
 
- capabilities
- ad hoc-mode and AP-mode 802.11 stations advertise their capabilities in
      802.11 Beacons and Probe Responses. wlanctlunderstands these capability flags:
      
        | Flag | Description |  
        | ess | infrastructure (access point) network |  
        | ibss | ad hoc network (no access point) |  
        | cf pollable | TBD |  
        | request cf poll | TBD |  
        | privacy | WEP encryption |  
        | short preamble | reduce 802.11b overhead |  
        | pbcc | 22Mbps ``802.11b+'' |  
        | channel agility | change channel for licensed services |  
        | short slot-time | TBD |  
        | rsn | TBD Real Soon Now |  
        | dsss-ofdm | TBD |  
 
- beacon-interval
- In the example, beacons are sent once every 100 Time Units. A Time Unit
      (TU) is 1024 microseconds (a “kilo-microsecond” or
      “kus”). Thus 100 TU is about one tenth of a second.
- tsft
- 802.11 stations keep a Time Synchronization Function Timer (TSFT) which
      counts up in microseconds. Ad hoc-mode stations synchronize time with
      their peers. Infrastructure-mode stations synchronize time with their
      access point. Power-saving stations wake and sleep at intervals measured
      by the TSF Timer. The TSF Timer has a role in the coalescence of 802.11 ad
      hoc networks (“IBSS merges”).
- rates
- 802.11 stations indicate the bit-rates they support, in units of 100kb/s
      in 802.11 Beacons, Probe Responses, and Association Requests.
      wlanctlprints a station's supported bit-rates in
      1Mb/s units. A station's basic rates are flagged by an asterisk
      (‘*’). The last bit-rate at which a packet was sent to the
      station is enclosed by square brackets.
- assoc-id
- In an infrastructure network, the access point assigns each client an
      Association Identifier which is used to indicate traffic for power-saving
      stations.
- assoc-failed
- The number of times the station tried and failed to associate with its
      access point. Only
- inactivity
- Seconds elapsed since a packet was last received from the station. When
      this value reaches net.link.ieee80211.maxinact, the station is eligible to
      be purged from the node table. See
      sysctl(8).
- rssi
- Unitless Received Signal Strength Indication (RSSI). Higher numbers
      indicate stronger signals. Zero is the lowest possible RSSI. On a hostap-
      or adhoc-mode interface, the node with node flag
      “bss” set uses rssi to indicate the
      signal strength for the last packet received from a station that does not
      belong to the network. On an infrastructure-mode station, the node with
      node flag “bss” set indicates the
      strength of packets from the access point.
- txseq
- The next 802.11 packet sent to this station will carry this transmit
      sequence number. The 802.11 MAC uses the transmit sequence number to
      detect duplicate packets.
- rxseq
- The last packet received from this station carried this transmit sequence
      number.
wlanctl first appeared in NetBSD
  3.0.