Manual browser: ral(4)
|RAL(4)||Kernel Interfaces Manual||RAL(4)|
NAMEral — Ralink Technology IEEE 802.11a/b/g wireless network driver
SYNOPSISral* at cardbus?
ral* at pci?
ral* at uhub? port ?
DESCRIPTIONThe ral driver supports PCI/CardBus wireless adapters based on the Ralink RT2500, RT2501, and RT2600 chipsets. The ral driver supports USB 2.0 wireless adapters based on the Ralink RT2500USB chipset.
The RT2500 chipset is the first generation of 802.11b/g adapters from Ralink. It consists of two integrated chips, an RT2560 or RT2570(USB) MAC/BBP and an RT2525 or RT2526(USB) radio transceiver.
The RT2501 chipset is the second generation of 802.11b/g adapters from Ralink. It consists of two integrated chips, an RT2561 MAC/BBP and an RT2527 radio transceiver. This chipset provides support for the IEEE 802.11e standard with multiple hardware transmission queues and allows scatter/gather for efficient DMA operations.
The RT2600 chipset consists of two integrated chips, an RT2661 MAC/BBP and an RT2529 radio transceiver. This chipset uses the MIMO (multiple-input multiple-output) technology with multiple antennas to extend the operating range of the adapter and to achieve higher throughput. MIMO will be the basis of the future IEEE 802.11n standard.
These are the modes the ral 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.
ral 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.
The transmit speed is user-selectable or can be adapted automatically by the driver depending on the received signal strength and on the number of hardware transmission retries. See rssadapt(9) for more information.
CONFIGURATIONThe ral 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.
- 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.
- 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 ral driver supports the following media types:
- Enable autoselection of the media type and options.
- Set 802.11b DS 1Mbps operation.
- Set 802.11b DS 2Mbps operation.
- Set 802.11b DS 5.5Mbps operation.
- Set 802.11b DS 11Mbps operation.
- Set 802.11a/g OFDM 6Mbps operation.
- Set 802.11a/g OFDM 9Mbps operation.
- Set 802.11a/g OFDM 12Mbps operation.
- Set 802.11a/g OFDM 18Mbps operation.
- Set 802.11a/g OFDM 24Mbps operation.
- Set 802.11a/g OFDM 36Mbps operation.
- Set 802.11a/g OFDM 48Mbps operation.
- Set 802.11a/g OFDM 54Mbps operation.
- mediaopt opts
The ral driver supports the following media options:
- Select Host AP operation.
- Select IBSS operation.
- Select monitor mode.
- -mediaopt opts
- Disable the specified media options on the driver and return it to the default mode of operation (BSS).
- mode mode
The ral driver supports the following modes:
- Force 802.11a operation.
- Force 802.11b operation.
- Force 802.11g operation.
- nwid 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 ral 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. ral is capable of using both 40-bit (5 characters or 10 hexadecimal digits) or 104-bit (13 characters or 26 hexadecimal digits) keys.
- Disable WEP encryption. This is the default mode of operation.
FILESThe following firmware files are potentially loaded when an interface is brought up:
RT2500 adapters do not require a firmware to operate.
HARDWAREThe following PCI adapters should work:
The following CardBus adapters should work:
The following Mini PCI adapters should work:
The following USB 2.0 adapters should work:
EXAMPLESThe following ifconfig.if(5) example creates a host-based access point on boot:
inet 192.168.1.1 netmask 255.255.255.0 media autoselect \ mediaopt hostap nwid my_net chan 11
Configure ral0 for WEP, using hex key “0x1deadbeef1”:
# ifconfig ral0 nwkey 0x1deadbeef1
Return ral0 to its default settings:
# ifconfig ral0 -bssid -chan media autoselect \ nwid "" -nwkey
Join an existing BSS network, “my_net”:
# ifconfig ral0 192.168.1.1 netmask 0xffffff00 nwid my_net
- ral%d: could not read microcode %s
- For some reason, the driver was unable to read the microcode file from the filesystem. The file might be missing or corrupted.
- ral%d: could not load 8051 microcode
- An error occurred while attempting to upload the microcode to the onboard 8051 microcontroller unit.
- ral%d: timeout waiting for MCU to initialize
- The onboard 8051 microcontroller unit failed to initialize in time.
- ral%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.
SEE ALSOarp(4), cardbus(4), ifmedia(4), intro(4), netintro(4), pci(4), usb(4), ifconfig.if(5), hostapd(8), ifconfig(8)
HISTORYThe ral driver first appeared in OpenBSD 3.7 and in NetBSD 3.0. Support for the RT2501 and RT2600 chipsets was added in OpenBSD 3.9 and in NetBSD 4.0.
AUTHORSThe ral driver was written by <email@example.com>.
CAVEATSSome PCI ral adapters seem to strictly require a system supporting PCI 2.2 or greater and will likely not work in systems based on older revisions of the PCI specification. Check the board's PCI version before purchasing the card.
The USB ral driver supports automatic control of the transmit speed in BSS mode only. Therefore the use of a USB ral adapter in Host AP mode is discouraged.
|December 13, 2009||NetBSD 7.0|