IWN(4)

NAME
iwn - Intel WiFi Link and Centrino IEEE 802.11a/b/g/n wireless network device

SYNOPSIS
iwn* at pci?

DESCRIPTION
The iwn driver provides support for Intel Wireless WiFi Link 4965/5000/1000 and Centrino Wireless-N 1000/2000/6000 Series PCIe Mini Card network adapters.

The Intel Wireless WiFi Link 4965AGN (codenamed Kedron) is a PCIe Mini Card network adapter that operates in the 2GHz and 5GHz spectra. It has 2 transmit paths and 3 receiver paths (2T3R). It is part of the fourth-generation Centrino platform (codenamed Santa Rosa).

The Intel WiFi Link 5000 series is a family of wireless network adapters that operate in the 2GHz and 5GHz spectra. They are part of the fifth-generation Centrino platform (codenamed Montevina). These adapters are available in both PCIe Mini Card (model code ending by MMW) and PCIe Half Mini Card (model code ending by HMW) form factor. The iwn driver provides support for the 5100 (codenamed Shirley Peak 1x2), 5150 (codenamed Echo Peak-V), 5300 (codenamed Shirley Peak 3x3) and 5350 (codenamed Echo Peak-P) adapters. The 5100 and 5150 adapters have 1 transmit path and 2 receiver paths (1T2R). The 5300 and 5350 adapters have 3 transmit paths and 3 receiver paths (3T3R).

The Intel WiFi Link 1000 (codenamed Condor Peak) is a single-chip wireless network adapter that operates in the 2GHz spectrum. It is part of the sixth-generation Centrino platform (codenamed Calpella). It is available in both PCIe Mini Card (model code ending by MMW) and PCIe Half Mini Card (model code ending by HMW) form factor. It has 1 transmit path and 2 receiver paths (1T2R).

The Intel Centrino Ultimate-N 6300 (codenamed Puma Peak 3x3) is a single-chip wireless network adapter that operates in the 2GHz and 5GHz spectra. It has 3 transmit paths and 3 receiver paths (3T3R). The Intel Centrino Advanced-N 6250 (codenamed Kilmer Peak) is a combo WiFi/WiMAX network adapter that operates in the 2GHz and 5GHz spectra. It has 2 transmit paths and 2 receiver paths (2T2R). The Intel Centrino Advanced-N 6200 (codenamed Puma Peak 2x2) is a wireless network adapter that operates in the 2GHz and 5GHz spectra. It has 2 transmit paths and 2 receiver paths (2T2R). These adapters are part of the sixth-generation Centrino platform (codenamed Calpella).

The Intel Centrino Wireless-N 2230 (codename Jackson Peak) and Intel Centrino Wireless-N 2200 (codename Marble Peak) are wireless network adapters that operate in the 2GHz spectrum. These adapters have 2 transmit paths and 2 receiver paths (2T2R). The Intel Centrino Wireless-N 135 and Intel Centrino Wireless-N 105 (codename Canyon Peak) also operate in the 2GHz spectrum. These adapters have 1 transmit path and 1 receiver path (1T1R).

These are the modes the iwn 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.

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 iwn driver can be configured to use Wired Equivalent Privacy (WEP) or Wi-Fi Protected Access (WPA1 and WPA2). WPA2 is currently the most secure encryption standard for wireless networks supported by OpenBSD. It is strongly recommended that neither WEP nor WPA1 are used as the sole mechanism to secure wireless communication, due to serious weaknesses. WPA1 is disabled by default and may be enabled using the option "wpaprotos wpa1,wpa2". For standard WPA networks which use pre-shared keys (PSK), keys are configured using the "wpakey" option. WPA-Enterprise networks require use of the wpa_supplicant package. The iwn driver offloads both encryption and decryption of unicast data frames to the hardware for the CCMP cipher.

In BSS mode the driver supports powersave mode and background scanning; see ifconfig(8).

The iwn driver can be configured at runtime with ifconfig(8) or on boot with hostname.if(5).

FILES
The driver needs at least version 5.6 of the following firmware files, which are loaded when an interface is brought up:

/etc/firmware/iwn-4965
/etc/firmware/iwn-5000
/etc/firmware/iwn-5150
/etc/firmware/iwn-1000
/etc/firmware/iwn-6000
/etc/firmware/iwn-6050
/etc/firmware/iwn-6005
/etc/firmware/iwn-6030
/etc/firmware/iwn-2030
/etc/firmware/iwn-2000
/etc/firmware/iwn-135
/etc/firmware/iwn-105

These firmware files are not free because Intel refuses to grant distribution rights without contractual obligations. As a result, even though OpenBSD includes the driver, the firmware files cannot be included and users have to download these files on their own.

A prepackaged version of the firmware can be installed using fw_update(8).

EXAMPLES
The following example scans for available networks:

    # ifconfig iwn0 scan

The following hostname.if(5) example configures iwn0 to join network “mynwid”, using WPA key “mywpakey”, obtaining an IP address using DHCP:

    join mynwid wpakey mywpakey
    inet autoconf

DIAGNOSTICS

iwn0: 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.

iwn0: fatal firmware error For some reason, the firmware crashed. The driver will reset the hardware. This should not happen.

iwn0: radio is disabled by hardware switch The radio transmitter is off and thus no packet can go out. The driver will reset the hardware. Make sure the laptop radio switch is on.

iwn0: could not read firmware ... (error N) For some reason, the driver was unable to read the firmware image from the filesystem. The file might be missing or corrupted.

iwn0: firmware too short: N bytes The firmware image is corrupted and can't be loaded into the adapter.

iwn0: could not load firmware An attempt to load the firmware into the adapter failed. The driver will reset the hardware.

SEE ALSO
arp(4), ifmedia(4), intro(4), netintro(4), pci(4), hostname.if(5), ifconfig(8)

HISTORY
The iwn device driver first appeared in OpenBSD 4.3.

AUTHORS
The iwn driver was written by Damien Bergamini <damien.bergamini@free.fr>.

CAVEATS
802.11n operation is currently limited to data rates MCS 0 to MCS 7.