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RTW(4)                       Device Drivers Manual                      RTW(4)

     rtw - Realtek RTL8180L IEEE 802.11b wireless network driver

     rtw* at cardbus? function ?
     rtw* at pci? dev ? function ?

     The rtw driver supports PCI/CardBus 802.11b wireless adapters based on
     the Realtek RTL8180L.

     A variety of radio transceivers can be found in these devices, including
     the Philips SA2400A, Maxim MAX2820, and GCT GRF5101, though not all of
     them are currently supported.

     These are the modes the rtw driver can operate in:

     BSS mode       Also known as infrastructure mode, this is used when
                    associating with an access point, through which all
                    traffic passes.  This mode is the default.

     IBSS mode      Also known as IEEE ad-hoc mode or peer-to-peer mode.  This
                    is the standardized method of operating without an access
                    point.  Stations associate with a service set.  However,
                    actual connections between stations are peer-to-peer.

     Host AP        In this mode the driver acts as an access point (base
                    station) for other cards.

     monitor mode   In this mode the driver is able to receive packets without
                    associating with an access point.  This disables the
                    internal receive filter and enables the card to capture
                    packets from networks which it wouldn't normally have
                    access to, or to scan for access points.

     rtw supports software WEP.  Wired Equivalent Privacy (WEP) is the de
     facto encryption standard for wireless networks.  It can be typically
     configured in one of three modes: no encryption; 40-bit encryption; or
     104-bit encryption.  Unfortunately, due to serious weaknesses in WEP
     protocol it is strongly recommended that it not be used as the sole
     mechanism to secure wireless communication.  WEP is not enabled by

     The rtw driver can be configured at runtime with ifconfig(8) or on boot
     with ifconfig.if(5) using the following parameters:

     bssid bssid
             Set the desired BSSID.

     -bssid  Unset the desired BSSID.  The interface will automatically select
             a BSSID in this mode, which is the default.

     chan n  Set the channel (radio frequency) to be used by the driver based
             on the given channel ID n.

     -chan   Unset the desired channel to be used by the driver.  The driver
             will automatically select a channel in this mode, which is the

     media media
             The rtw driver supports the following media types:

             autoselect  Enable autoselection of the media type and options.
             DS1         Set 802.11b DS 1Mbps operation.
             DS2         Set 802.11b DS 2Mbps operation.
             DS5         Set 802.11b DS 5.5Mbps operation.
             DS11        Set 802.11b DS 11Mbps operation.

     mediaopt opts
             The rtw driver supports the following media options:

             hostap   Select Host AP operation.
             ibss     Select IBSS operation.
             monitor  Select monitor mode.

     -mediaopt opts
             Disable the specified media options on the driver and return it
             to the default mode of operation (BSS).

     ssid id
             Set the network ID.  The id can either be any text string up to
             32 characters in length, or a series of hexadecimal digits up to
             64 digits.  An empty id string allows the interface to connect to
             any available access points.  By default the rtw driver uses an
             empty string.  Note that network ID is synonymous with Extended
             Service Set ID (ESSID).

     nwkey key
             Enable WEP encryption using the specified key.  The key can
             either be a string, a series of hexadecimal digits (preceded by
             `0x'), or a set of keys of the form "n:k1,k2,k3,k4", where `n'
             specifies which of the keys will be used for transmitted packets,
             and the four keys, "k1" through "k4", are configured as WEP keys.
             If a set of keys is specified, a comma (`,') within the key must
             be escaped with a backslash.  Note that if multiple keys are
             used, their order must be the same within the network.  rtw is
             capable of using both 40-bit (5 characters or 10 hexadecimal
             digits) or 104-bit (13 characters or 26 hexadecimal digits) keys.

     -nwkey  Disable WEP encryption.  This is the default mode of operation.

     nwkey persist
             Enable WEP encryption with the persistent key stored in the
             network card.

     The following adapters should work:

           Card                            Bus
           Belkin F5D6020 V3               CardBus
           Buffalo WLI-CB-B11              CardBus
           Corega CG-WLCB11V3              CardBus
           D-Link DWL-610                  CardBus
           Level-One WPC-0101              CardBus
           Linksys WPC11 v4                CardBus
           Netgear MA521                   CardBus
           Ovislink AirLive WL-1120PCM     CardBus
           Planet WL-3553                  CardBus
           TrendNET TEW-266PC              CardBus
           VCTnet PC-11B1                  CardBus

     The following ifconfig.if(5) example creates a host-based access point on

           inet NONE media autoselect \
                   mediaopt hostap ssid my_net chan 11

     Configure rtw0 for WEP, using hex key "0x1deadbeef1":

           # ifconfig rtw0 nwkey 0x1deadbeef1

     Return rtw0 to its default settings:

           # ifconfig rtw0 -bssid -chan media autoselect \
                   ssid "" -nwkey

     Join an existing BSS network, "my_net":

           # ifconfig rtw0 netmask 0xffffff00 ssid my_net

     arp(4), cardbus(4), ifmedia(4), intro(4), netintro(4), pci(4),
     ifconfig.if(5), ifconfig(8)

     Realtek, http://www.realtek.com.tw.

     The rtw device driver first appeared in NetBSD 3.0 and then in
     OpenBSD 3.7.

     The rtw driver was written by David Young <dyoung@NetBSD.org> and ported
     to OpenBSD by Jonathan Gray <jsg@openbsd.org>, who wrote this man page.

     Only the Philips SA2400A and Maxim MAX2820 RF transceivers are known to
     work.  Devices incorporating a GCT RF transceiver are not supported due
     to a lack of documentation from GCT.

     While PCI devices will attach most of them are not able to transmit.

NetBSD 10.99                   December 29, 2004                  NetBSD 10.99