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Driver for USB 2.0 wireless adapters based on the Ralink RT2501USB and RT2601USB chipsets


io-pkt-variant -d rum ... &

where variant is one of v4, v4-hc, or v6-hc.

Runs on:





The driver supports USB 2.0 wireless adapters based on the Ralink RT2501USB and RT2601USB chipsets. This is a ported NetBSD driver; its interface names are in the form rumX, where X is an integer.

The RT2501USB chipset is the second generation of 802.11a/b/g adapters from Ralink. It consists of two integrated chips, an RT2571W MAC/BBP and an RT2528 or RT5226 radio transceiver.

The RT2601USB chipset consists of two integrated chips, an RT2671 MAC/BBP and an RT2527 or RT5225 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.

This driver can operate in the following modes:

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.

The driver 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.

You can also use this driver in conjunction with wpa_supplicant to provide WPA / WPA2 encryption.

You can use ifconfig to configure the driver at runtime:

bssid bssid
Set the desired BSSID.
Unset the desired BSSID. The interface automatically selects 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 automatically selects a channel in this mode, which is the default.
media media
This driver supports the following media types:
mediaopt opts
This driver supports the following media options:
-mediaopt opts
Disable the specified media options on the driver and return it to the default mode of operation (BSS).
mode mode
This driver supports the following modes:
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 (the default) allows the interface to connect to any available access points. 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 to use 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: If you use multiple keys, their order must be the same within the network. The driver can use 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.

See also:

devn-*, devnp-*, ifconfig, io-pkt