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ANCONTROL(8)            FreeBSD System Manager's Manual           ANCONTROL(8)

     ancontrol -- configure Aironet 4500/4800 devices

     ancontrol -i iface -A
     ancontrol -i iface -N
     ancontrol -i iface -S
     ancontrol -i iface -I
     ancontrol -i iface -T
     ancontrol -i iface -C
     ancontrol -i iface -Q
     ancontrol -i iface -Z
     ancontrol -i iface -R
     ancontrol -i iface -t 0-4
     ancontrol -i iface -s 0-3
     ancontrol -i iface [-v 1-4] -a AP
     ancontrol -i iface -b beacon_period
     ancontrol -i iface [-v 0 | 1] -d 0-3
     ancontrol -i iface -e 0-4
     ancontrol -i iface [-v 0-8] -k key
     ancontrol -i iface -K 0-2
     ancontrol -i iface -W 0-2
     ancontrol -i iface -L user_name
     ancontrol -i iface -j netjoin_timeout
     ancontrol -i iface -l station_name
     ancontrol -i iface -m mac_address
     ancontrol -i iface [-v 1-3] -n SSID
     ancontrol -i iface -o 0 | 1
     ancontrol -i iface -p tx_power
     ancontrol -i iface -c frequency
     ancontrol -i iface -f fragmentation_threshold
     ancontrol -i iface -r RTS_threshold
     ancontrol -i iface -M 0-15
     ancontrol -h

     The ancontrol utility controls the operation of Aironet wireless network-
     ing devices via the an(4) driver.  Most of the parameters that can be
     changed relate to the IEEE 802.11 protocol which the Aironet cards imple-
     ment.  This includes such things as the station name, whether the station
     is operating in ad-hoc (point to point) or infrastructure mode, and the
     network name of a service set to join.  The ancontrol utility can also be
     used to view the current NIC status, configuration and to dump out the
     values of the card's statistics counters.

     The iface argument given to ancontrol should be the logical interface
     name associated with the Aironet device (an0, an1, etc.).  If one is not
     specified the device ``an0'' will be assumed.

     The ancontrol utility is not designed to support the combination of argu-
     ments from different SYNOPSIS lines in a single ancontrol invocation, and
     such combinations are not recommended.

     The options are as follows:

     -i iface -A
             Display the preferred access point list.  The AP list can be used
             by stations to specify the MAC address of access points with
             which it wishes to associate.  If no AP list is specified (the
             default) then the station will associate with the first access
             point that it finds which serves the SSID(s) specified in the
             SSID list.  The AP list can be modified with the -a option.

     -i iface -N
             Display the SSID list.  This is a list of service set IDs (i.e.,
             network names) with which the station wishes to associate.  There
             may be up to three SSIDs in the list: the station will go through
             the list in ascending order and associate with the first matching
             SSID that it finds.

     -i iface -S
             Display NIC status information.  This includes the current oper-
             ating status, current BSSID, SSID, channel, beacon period and
             currently associated access point.  The operating mode indicates
             the state of the NIC, MAC status and receiver status.  When the
             "synced" keyword appears, it means the NIC has successfully asso-
             ciated with an access point, associated with an ad-hoc ``master''
             station, or become a ``master'' itself.  The beacon period can be
             anything between 20 and 976 milliseconds.  The default is 100.

     -i iface -I
             Display NIC capability information.  This shows the device type,
             frequency, speed and power level capabilities and firmware revi-
             sion levels.

     -i iface -T
             Display the NIC's internal statistics counters.

     -i iface -C
             Display current NIC configuration.  This shows the current opera-
             tion mode, receive mode, MAC address, power save settings, vari-
             ous timing settings, channel selection, diversity, transmit power
             and transmit speed.

     -i iface -Q
             Display the cached signal strength information maintained by the
             an(4) driver.  The driver retains information about signal
             strength and noise level for packets received from different
             hosts.  The signal strength and noise level values are displayed
             in units of dBms by default.  The sysctl(8)
             variable can be set to raw, dbm or per.

     -i iface -Z
             Clear the signal strength cache maintained internally by the
             an(4) driver.

     -i iface -R
             Display RSSI map that converts from the RSSI index to percent and

     -i iface -t 0-4
             Select transmit speed.  The available settings are as follows:

                   TX rate    NIC speed
                   0          Auto -- NIC selects optimal speed
                   1          1Mbps fixed
                   2          2Mbps fixed
                   3          5.5Mbps fixed
                   4          11Mbps fixed

             Note that the 5.5 and 11Mbps settings are only supported on the
             4800 series adapters: the 4500 series adapters have a maximum
             speed of 2Mbps.

     -i iface -s 0-3
             Set power save mode.  Valid selections are as follows:

                   Selection    Power save mode
                   0            None - power save disabled
                   1            Constantly awake mode (CAM)
                   2            Power Save Polling (PSP)
                   3            Fast Power Save Polling (PSP-CAM)

             Note that for IBSS (ad-hoc) mode, only PSP mode is supported, and
             only if the ATIM window is non-zero.

     -i iface [-v 1-4] -a AP
             Set preferred access point.  The AP is specified as a MAC address
             consisting of 6 hexadecimal values separated by colons.  By
             default, the -a option only sets the first entry in the AP list.
             The -v modifier can be used to specify exactly which AP list
             entry is to be modified.  If the -v flag is not used, the first
             AP list entry will be changed.

     -i iface -b beacon_period
             Set the ad-hoc mode beacon period.  The beacon_period is speci-
             fied in milliseconds.  The default is 100ms.

     -i iface [-v 0 | 1] -d 0-3
             Select the antenna diversity.  Aironet devices can be configured
             with up to two antennas, and transmit and receive diversity can
             be configured accordingly.  Valid selections are as follows:

                   Selection    Diversity
                   0            Select factory default diversity
                   1            Antenna 1 only
                   2            Antenna 2 only
                   3            Antenna 1 and 2

             The receive and transmit diversity can be set independently.  The
             user must specify which diversity setting is to be modified by
             using the -v option: selection 0 sets the receive diversity and 1
             sets the transmit diversity.

     -i iface -e 0-4
             Set the transmit WEP key to use.  Note that until this command is
             issued, the device will use the last key programmed.  The trans-
             mit key is stored in NVRAM.  Currently set transmit key can be
             checked via -C option.  Selection 4 sets the card in ``Home
             Network Mode'' and uses the home key.

     -i iface [-v 0-8] -k key
             Set a WEP key.  For 40 bit prefix 10 hex character with 0x.  For
             128 bit prefix 26 hex character with 0x.  Use "" as the key to
             erase the key.  Supports 4 keys; even numbers are for permanent
             keys and odd number are for temporary keys.  For example, -v 1
             sets the first temporary key.  (A ``permanent'' key is stored in
             NVRAM; a ``temporary'' key is not.)  Note that the device will
             use the most recently-programmed key by default.  Currently set
             keys can be checked via -C option, only the sizes of the keys are
             returned.  The value of 8 is for the home key.  Note that the
             value for the home key can be read back from firmware.

     -i iface -K 0-2
             Set authorization type.  Use 0 for none, 1 for ``Open'', 2 for
             ``Shared Key''.

     -i iface -W 0-2
             Enable WEP.  Use 0 for no WEP, 1 to enable full WEP, 2 for mixed

     -i iface -L user_name
             Enable LEAP and query for password.  It will check to see if it
             has authenticated for up to 60s.  To disable LEAP, set WEP mode.

     -i iface -j netjoin_timeout
             Set the ad-hoc network join timeout.  When a station is first
             activated in ad-hoc mode, it will search out a ``master'' station
             with the desired SSID and associate with it.  If the station is
             unable to locate another station with the same SSID after a suit-
             able timeout, it sets itself up as the ``master'' so that other
             stations may associate with it.  This timeout defaults to 10000
             milliseconds (10 seconds) but may be changed with this option.
             The timeout should be specified in milliseconds.

     -i iface -l station_name
             Set the station name used internally by the NIC.  The
             station_name can be any text string up to 16 characters in
             length.  The default name is set by the driver to ``FreeBSD''.

     -i iface -m mac_address
             Set the station address for the specified interface.  The
             mac_address is specified as a series of six hexadecimal values
             separated by colons, e.g.: 00:60:1d:12:34:56.  This programs the
             new address into the card and updates the interface as well.

     -i iface [-v 1-3] -n SSID
             Set the desired SSID (network name).  There are three SSIDs which
             allows the NIC to work with access points at several locations
             without needing to be reconfigured.  The NIC checks each SSID in
             sequence when searching for a match.  The SSID to be changed can
             be specified with the -v modifier option.  If the -v flag is not
             used, the first SSID in the list is set.

     -i iface -o 0 | 1
             Set the operating mode of the Aironet interface.  Valid selec-
             tions are 0 for ad-hoc mode and 1 for infrastructure mode.  The
             default driver setting is for infrastructure mode.

     -i iface -p tx_power
             Set the transmit power level in milliwatts.  Valid power settings
             vary depending on the actual NIC and can be viewed by dumping the
             device capabilities with the -I flag.  Typical values are 1, 5,
             20, 50 and 100mW.  Selecting 0 sets the factory default.

     -i iface -c frequency
             Set the radio frequency of a given interface.  The frequency
             should be specified as a channel ID as shown in the table below.
             The list of available frequencies is dependent on radio regula-
             tions specified by regional authorities.  Recognized regulatory
             authorities include the FCC (United States), ETSI (Europe),
             France and Japan.  Frequencies in the table are specified in MHz.

                   Channel ID   FCC   ETSI   France   Japan
                   1            2412  2412   -        -
                   2            2417  2417   -        -
                   3            2422  2422   -        -
                   4            2427  2427   -        -
                   5            2432  2432   -        -
                   6            2437  2437   -        -
                   7            2442  2442   -        -
                   8            2447  2447   -        -
                   9            2452  2452   -        -
                   10           2457  2457   2457     -
                   11           2462  2462   2462     -
                   12           -     2467   2467     -
                   13           -     2472   2472     -
                   14           -     -      -        2484

             If an illegal channel is specified, the NIC will revert to its
             default channel.  For NICs sold in the United States and Europe,
             the default channel is 3.  For NICs sold in France, the default
             channel is 11.  For NICs sold in Japan, the only available chan-
             nel is 14.  Note that two stations must be set to the same chan-
             nel in order to communicate.

     -i iface -f fragmentation_threshold
             Set the fragmentation threshold in bytes.  This threshold con-
             trols the point at which outgoing packets will be split into mul-
             tiple fragments.  If a single fragment is not sent successfully,
             only that fragment will need to be retransmitted instead of the
             whole packet.  The fragmentation threshold can be anything from
             64 to 2312 bytes.  The default is 2312.

     -i iface -r RTS_threshold
             Set the RTS/CTS threshold for a given interface.  This controls
             the number of bytes used for the RTS/CTS handshake boundary.  The
             RTS_threshold can be any value between 0 and 2312.  The default
             is 2312.

     -i iface -M 0-15
             Set monitor mode via bit mask, meaning:

                   Bit     Meaning
                   0       to not dump 802.11 packet.
                   1       to enable 802.11 monitor.
                   2       to monitor any SSID.
                   4       to not skip beacons, monitor beacons produces a
                           high system load.
                   8       to enable full Aironet header returned via BPF.
                           Note it appears that a SSID must be set.

     -h      Print a list of available options and sample usage.

     WEP (``wired equivalent privacy'') is based on the RC4 algorithm, using a
     24 bit initialization vector.

     RC4 is supposedly vulnerable to certain known plaintext attacks, espe-
     cially with 40 bit keys.  So the security of WEP in part depends on how
     much known plaintext is transmitted.

     Because of this, although counter-intuitive, using ``shared key'' authen-
     tication (which involves sending known plaintext) is less secure than
     using ``open'' authentication when WEP is enabled.

     Devices may alternate among all of the configured WEP keys when transmit-
     ting packets.  Therefore, all configured keys (up to four) must agree.

           ancontrol -i an0 -v 0 -k 0x12345678901234567890123456
           ancontrol -i an0 -K 2
           ancontrol -i an0 -W 1
           ancontrol -i an0 -e 0

     Sets a WEP key 0, enables ``Shared Key'' authentication, enables full WEP
     and uses transmit key 0.

     an(4), ifconfig(8)

     The ancontrol utility first appeared in FreeBSD 4.0.

     The ancontrol utility was written by Bill Paul <>.

     The statistics counters do not seem to show the amount of transmit and
     received frames as increasing.  This is likely due to the fact that the
     an(4) driver uses unmodified packet mode instead of letting the NIC per-
     form 802.11/ethernet encapsulation itself.

     Setting the channel does not seem to have any effect.

FreeBSD 6.2                   September 10, 1999                   FreeBSD 6.2


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