.\" $OpenBSD: rsu.4,v 1.7 2011/06/09 14:21:11 deraadt Exp $
.\"
.\" Copyright (c) 2010 Damien Bergamini <damien.bergamini@free.fr>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate: June 9 2011 $
.Dt RSU 4
.Os
.Sh NAME
.Nm rsu
.Nd Realtek RTL8188SU/RTL8192SU USB IEEE 802.11b/g/n wireless network device
.Sh SYNOPSIS
.Cd "rsu* at uhub? port ?"
.Sh DESCRIPTION
The
.Nm
driver supports USB 2.0 wireless network devices based on Realtek
RTL8188SU, RTL8191SU and RTL8192SU chipsets.
.Pp
The RTL8188SU 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.
.Pp
The RTL8191SU is a highly integrated multiple-in, single-out (MISO)
802.11n adapter that combines a MAC, a 1T2R capable baseband and an
RF in a single chip.
It operates in the 2GHz spectrum only.
.Pp
The RTL8192SU is a highly integrated multiple-in, multiple-out (MIMO)
802.11n adapter that combines a MAC, a 2T2R capable baseband and an
RF in a single chip.
It operates in the 2GHz spectrum only.
.Pp
These are the modes the
.Nm
driver can operate in:
.Bl -tag -width "IBSS-masterXX"
.It BSS mode
Also known as
.Em infrastructure
mode, this is used when associating with an access point, through
which all traffic passes.
This mode is the default.
.El
.Pp
The
.Nm
driver can be configured to use
Wired Equivalent Privacy (WEP) or
Wi-Fi Protected Access (WPA-PSK and WPA2-PSK).
WPA is the de facto 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.
.Pp
The
.Nm
driver can be configured at runtime with
.Xr ifconfig 8
or on boot with
.Xr hostname.if 5 .
.Sh FILES
The driver needs at least version 1.1 of the following firmware file,
which is loaded when an interface is attached:
.Pp
.Bl -tag -width Ds -offset indent -compact
.It /etc/firmware/rsu-rtl8712fw
.El
.Pp
A prepackaged version of the firmware, designed to be used with
.Xr pkg_add 1 ,
can be found at:
.Bd -literal -offset 3n
http://firmware.openbsd.org/firmware/rsu-firmware-1.1.tgz
.Ed
.Sh HARDWARE
The following adapters should work:
.Pp
.Bl -tag -width Ds -offset indent -compact
.It ASUS USB-N10
.It D-Link DWA-131 A1
.It Hercules HWGUn-54
.It Hercules HWNUm-300
.It Planex GW-USNano
.It Sitecom WL-349 v1
.It Sitecom WL-353
.It Sweex LW154
.It TRENDnet TEW-648UB
.It TRENDnet TEW-649UB
.El
.Sh EXAMPLES
The following
.Xr hostname.if 5
example configures rsu0 to join whatever network is available on boot,
using WEP key
.Dq 0x1deadbeef1 ,
channel 11, obtaining an IP address using DHCP:
.Bd -literal -offset indent
dhcp NONE NONE NONE nwkey 0x1deadbeef1 chan 11
.Ed
.Pp
Configure rsu0 to join network
.Dq my_net
using WPA with passphrase
.Dq my_passphrase :
.Bd -literal -offset indent
# ifconfig rsu0 nwid my_net wpakey my_passphrase
.Ed
.Pp
Join an existing BSS network,
.Dq my_net :
.Bd -literal -offset indent
# ifconfig rsu0 192.168.1.1 netmask 0xffffff00 nwid my_net
.Ed
.Sh DIAGNOSTICS
.Bl -diag
.It "rsu%d: error %d, 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.
.It "rsu%d: 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.
.El
.Sh SEE ALSO
.Xr arp 4 ,
.Xr ifmedia 4 ,
.Xr intro 4 ,
.Xr netintro 4 ,
.Xr usb 4 ,
.Xr hostname.if 5 ,
.Xr ifconfig 8
.Sh HISTORY
The
.Nm
driver first appeared in
.Ox 4.9 .
.Sh AUTHORS
The
.Nm
driver was written by
.An Damien Bergamini Aq damien@openbsd.org
.
.Sh CAVEATS
The
.Nm
driver does not support any of the 802.11n capabilities offered by the
adapters.
Additional work is required in
.Xr ieee80211 9
before those features can be supported.