NAME
rtw —
Realtek RTL8180L IEEE 802.11b
wireless network driver
SYNOPSIS
rtw* at cardbus? function ?
rtw* at pci? dev ? function ?
DESCRIPTION
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 default.
CONFIGURATION
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
default.
-
-
- 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.
HARDWARE
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 |
EXAMPLES
The following
ifconfig.if(5)
example creates a host-based access point on boot:
inet 192.168.1.1 255.255.255.0 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 192.168.1.1 netmask 0xffffff00 ssid my_net
SEE ALSO
arp(4),
cardbus(4),
ifmedia(4),
intro(4),
netintro(4),
pci(4),
ifconfig.if(5),
ifconfig(8)
Realtek,
http://www.realtek.com.tw.
HISTORY
The
rtw device driver first appeared in
NetBSD 3.0 and then in
OpenBSD
3.7.
AUTHORS
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.
BUGS
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.