---
name: "if_rum"
section: "4"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd"]
url: "https://new.carta.tech/if_rum"
---

# if\_rum(4)

Ralink Technology USB IEEE 802.11a/b/g wireless network driver

## NAME

**rum** – Ralink Technology USB IEEE 802.11a/b/g wireless network driver

## SYNOPSIS

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

**device ehci** **device uhci** **device ohci** **device usb** **device rum** **device wlan** **device wlan\_amrr**

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

```
if_rum_load="YES"
```

## DESCRIPTION

The **rum** driver supports USB 2.0 and PCI Express Mini Card wireless adapters based on the Ralink RT2501USB and RT2601USB chipsets.

Ralink PCI Express Mini Card adapters show up as normal USB 2.0 devices and are thus handled by the **rum** driver.

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.

All chips have hardware support for WEP, AES-CCM, TKIP, and Michael cryptographic operations.

**rum** supports **station**, **adhoc**, **adhoc-demo**, **hostap**, and **monitor** mode operation. Only one virtual interface may be configured at any time. For more information on configuring this device, see [ifconfig(8)](/ifconfig/8.md).

## HARDWARE

The **rum** driver supports USB 2.0 wireless adapters based on the Ralink RT2501USB and RT2601USB chipsets, including:

| | |
| --- | --- |
| *Card* | *Bus* |
| 3Com Aolynk WUB320g | USB |
| Abocom WUG2700 Ta | USB |
| Airlink101 AWLL5025 | USB |
| ASUS WL-167g ver 2 | USB |
| Belkin F5D7050 ver 3 | USB |
| Belkin F5D9050 ver 3 | USB |
| Buffalo WLI-U2-SG54HP | USB |
| Buffalo WLI-U2-SG54HG | USB |
| Buffalo WLI-U2-G54HP | USB |
| Buffalo WLI-UC-G | USB |
| CNet CWD-854 ver F | USB |
| Conceptronic C54RU ver 2 | USB |
| Corega CG-WLUSB2GO | USB |
| D-Link DWA-110 | USB |
| D-Link DWA-111 | USB |
| D-Link DWL-G122 rev C1 | USB |
| D-Link WUA-1340 | USB |
| Digitus DN-7003GR | USB |
| Edimax EW-7318USG | USB |
| Gigabyte GN-WB01GS | USB |
| Gigabyte GN-WI05GS | USB |
| Hawking HWUG1 | USB |
| Hawking HWU54DM | USB |
| Hercules HWGUSB2-54-LB | USB |
| Hercules HWGUSB2-54V2-AP | USB |
| LevelOne WNC-0301USB v3 | USB |
| Linksys WUSB54G rev C | USB |
| Linksys WUSB54GR | USB |
| Planex GW-US54HP | USB |
| Planex GW-US54Mini2 | USB |
| Planex GW-USMM | USB |
| Senao NUB-3701 | USB |
| Sitecom WL-113 ver 2 | USB |
| Sitecom WL-172 | USB |
| Sweex LW053 | USB |
| TP-LINK TL-WN321G v1/v2/v3 | USB |

## EXAMPLES

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

```
ifconfig wlan create wlandev rum0 inet 192.0.2.20/24
```

Join a specific BSS network with network name *my\_net*:

```
ifconfig wlan create wlandev rum0 ssid my_net up
```

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

```
ifconfig wlan create wlandev rum0 ssid my_net \
    wepmode on wepkey 0x1234567890 weptxkey 1 up
```

Join a specific BSS network with 128-bit WEP encryption:

```
ifconfig wlan create wlandev rum0 wlanmode adhoc ssid my_net \
    wepmode on wepkey 0x01020304050607080910111213 weptxkey 1
```

## DIAGNOSTICS

- rum%d: could not load 8051 microcode

  An error occurred while attempting to upload the microcode to the onboard 8051 microcontroller unit. The driver will reset the hardware. This should not happen.

## SEE ALSO

[intro(4)](/intro/4.md), [netintro(4)](/netintro/4.md), [usb(4)](/usb/4.md), [wlan(4)](/wlan/4.md), [wlan\_amrr(4)](/wlan_amrr/4.md), [wlan\_ccmp(4)](/wlan_ccmp/4.md), [wlan\_tkip(4)](/wlan_tkip/4.md), [wlan\_wep(4)](/wlan_wep/4.md), [wlan\_xauth(4)](/wlan_xauth/4.md), [networking(7)](/networking/7.md), [hostapd(8)](/hostapd/8.md), [ifconfig(8)](/ifconfig/8.md), [wpa\_supplicant(8)](/wpa_supplicant/8.md)

## HISTORY

The **rum** driver first appeared in OpenBSD 4.0 and FreeBSD 7.0.

## AUTHORS

The original **rum** driver was written by Niall O'Higgins ⟨*niallo@openbsd.org*⟩ and Damien Bergamini ⟨*damien@openbsd.org*⟩.