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

     ancontrol - configure Aironet 4500/4800 devices

     ancontrol [interface] [-AChINQSTZ] [[-v 1|2|3|4] -a AP]
               [-b beacon_period] [-c channel] [-v 0|1 -d 0|1|2|3]
               [-e 0|1|2|3] [-f fragmentation_threshold] [-j netjoin_timeout]
               [-K 0|1|2] [-v 0|1|2|3|4|5|6|7 -k key] [-l station_name]
               [-m macaddress] [[-v 1|2|3] -n SSID] [-o 0|1] [-p tx_power]
               [-r RTS_threshold] [-s 0|1|2|3] [-t 0|1|2|3|4] [-W 0|1|2]

     The ancontrol command 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 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.  ancontrol can also be used to view the current
     NIC status, configuration, and to dump the values of the card's statis-
     tics counters.

     The interface argument given to ancontrol should be the logical interface
     name associated with the Aironet device (e.g., an0, an1, etc...).  If no
     interface is specified, `an0' is used.

     The options are as follows:

     -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.

     [-v 1|2|3|4] -a AP
             Set preferred access point.  The AP is specified as a MAC address
             consisting of 6 hexadecimal values separated by colons.  By de-
             fault, the -a option only sets the first entry in the AP list.
             The -v modifier can be used to specify exactly which AP list en-
             try is to be modified.  If the -v flag is not used, the first AP
             list entry will be changed.

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

     -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 pow-
             er, and transmit speed.

     -c channel
             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

                   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.

     -v 0|1 -d 0|1|2|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.

     -e 0|1|2|3
             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.  The currently set transmit key can
             be checked via -C option.

     -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.

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

     -I      Display NIC capability information.  This shows the device type,
             frequency, speed, power level capabilities, and firmware revision

     -j netjoin_timeout
             Set the ad-hoc network join timeout.  When a station is first ac-
             tivated 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 sta-
             tions may associate with it.  This timeout defaults to 10000 mil-
             liseconds (10 seconds) but may be changed with this option.  The
             timeout should be specified in milliseconds.

     -K 0|1|2
             Set authorization type.  Use 0 for none, 1 for "Open", 2 for
             "Shared Key".

     -v 0|1|2|3|4|5|6|7 -k key
             Set a WEP key.  For 40 bits, prefix 10 hex digits with 0x.  For
             128 bits, prefix 26 hex digits with 0x.  Use "" as the key to
             erase it.  Supports 4 keys; even numbers are for permanent keys
             and odd numbers 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 the -C option; only the sizes of the keys are re-

     -l station_name
             Set the station name used internally by the NIC.  station_name
             can be any text string up to 16 characters in length.  The de-
             fault name is set by the driver to "OpenBSD".

     -m macaddress
             Set the station address for the specified interface.  The
             macaddress 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.

     -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.

     [-v 1|2|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 isn't
             used, the first SSID in the list is set.

     -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.

     -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.

     -Q      If driver was compiled with option ANCACHE (default) then display
             the signal cache contents.  A maximum of 16 station addresses are
             collected on the list with LRU expiration policy.  Information
             such as MAC address, IP address, and signal strength is collected
             from the most recent matching packet received.

     -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.

     -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 as-
             sociated 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 de-
             fault is 100.

     -s 0|1|2|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.

     -T      Display the NIC's internal statistics counters.

     -t 0|1|2|3|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.

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

     -Z      Purge the signal cache contents (see above).

     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" authenti-
     cation (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.

     an(4), wi(4), hostname.if(5), ifconfig(8), wicontrol(8)

     The ancontrol command first appeared in FreeBSD 3.0 and OpenBSD 2.7.

     The ancontrol command was written by Bill Paul <wpaulATee.edu>
     and ported to OpenBSD by
     Michael Shalayeff <mickeyATopenbsd.org>.

     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.

OpenBSD 3.6                   September 10, 1999                             5