NAME

iwm — Intel 7000/8000 IEEE 802.11a/ac/b/g/n wireless network devices

SYNOPSIS

iwm* at pci?

DESCRIPTION

The iwm driver provides support for Intel Wireless 7260, 7265, 3160, 3165, 3168, 8260, and 8265 PCIe Mini Card network adapters.

These are the modes the iwm 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 iwm driver can be configured to use Wired Equivalent Privacy (WEP) or Wi-Fi Protected Access (WPA-PSK and WPA2-PSK). WPA is the current encryption standard for wireless networks. It is strongly recommended that WEP not be used as the sole mechanism to secure wireless communication, due to serious weaknesses in it. The iwm driver offloads both encryption and decryption of unicast data frames to the hardware for the CCMP cipher.

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

FILES

The driver needs one of the following firmware files, which are loaded when an interface is brought up:

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(1).

EXAMPLES

The following example scans for available networks:

The following hostname.if(5) example configures iwm0 to join network “mynwid”, using WPA key “mywpakey”, obtaining an IP address using DHCP:

nwid mynwid wpakey mywpakey
dhcp

DIAGNOSTICS

iwm0: 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.

iwm0: fatal firmware error

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

iwm0: 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.

iwm0: 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.

iwm0: firmware too short: N bytes

The firmware image is corrupted and can't be loaded into the adapter.

iwm0: 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 iwm device driver first appeared in OpenBSD 5.7.

CAVEATS

The iwm driver does not support any of the 802.11ac capabilities offered by the adapters. Support for 802.11n 40MHz channels and Tx aggregation is not yet implemented. Additional work is required in ieee80211(9) before those features can be supported.

This driver does not support powersave mode.