NAME

     rtwn — Realtek RTL8188CE PCIe IEEE 802.11b/g/n wireless network device

SYNOPSIS

     To compile this driver into the kernel, place the following lines in your kernel
     configuration file:

           device rtwn
           device rtwnfw
           device wlan
           device firmware

     Alternatively, to load the driver as a module at boot time, place the following line in
     loader.conf(5):

           if_rtwn_load="YES"

     After you have read the license in /usr/share/doc/legal/realtek.LICENSE you will want to add
     the following lines to loader.conf(5):

           legal.realtek.license_ack=1
           rtwn-rtl8192cfwU_load="YES"
           rtwn-rtl8192cfwU_B_load="YES"

DESCRIPTION

     The rtwn driver supports PCIe wireless network devices based on the Realtek RTL8188CE
     chipset.

     The RTL8188CE is a highly integrated 802.11n adapter that combines a MAC, a 1T1R capable
     baseband and an RF in a single chip.  It operates in the 2GHz spectrum only.

     These are the modes the rtwn 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.

     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.

     The rtwn driver can be configured to use Wired Equivalent Privacy (WEP) or Wi-Fi Protected
     Access (WPA-PSK and WPA2-PSK).  WPA is the current encryption standard for wireless
     networks.  It is strongly recommended that WEP not be used as the sole mechanism to secure
     wireless communication, due to serious weaknesses in it.

     The rtwn driver can be configured at runtime with ifconfig(8).

FILES

     The driver needs at least version 1.0 of the following firmware files, which are loaded when
     an interface is brought up:

           /boot/kernel/rtwn-rtl8192cfwU.ko
           /boot/kernel/rtwn-rtl8192cfwU_B.ko

EXAMPLES

     Join an existing BSS network (i.e., connect to an access point):

           ifconfig wlan create wlandev rtwn0 inet 192.168.0.20 \
               netmask 0xffffff00

     Join a specific BSS network with network name “my_net”:

           ifconfig wlan create wlandev rtwn0 ssid my_net up

     Join a specific BSS network with 64-bit WEP encryption:

           ifconfig wlan create wlandev rtwn0 ssid my_net \
                   wepmode on wepkey 0x1234567890 weptxkey 1 up

DIAGNOSTICS

     could not read firmware %s  For some reason, the driver was unable to read the microcode
     file from the filesystem.  The file might be missing or corrupted.

     device timeout  A frame dispatched to the hardware for transmission did not complete in
     time.  The driver will reset the hardware.  This should not happen.

SEE ALSO

     pci(4), rtwnfw(4), wlan(4), wlan_ccmp(4), wlan_tkip(4), wlan_wep(4), ifconfig(8),
     wpa_supplicant(8)

HISTORY

     The rtwn driver first appeared in OpenBSD 5.8.

AUTHORS

     The rtwn driver was written by Stefan Sperling <stsp@openbsd.org> and ported by Kevin Lo
     <kevlo@freebsd.org>.  It was based on the urtwn(4) driver written by Damien Bergamini
     <damien.bergamini@free.fr>.

CAVEATS

     The rtwn driver does not support any of the 802.11n capabilities offered by the adapters.
     Additional work is required in ieee80211(9) before those features can be supported.