Gentoo Wiki



Basic Setup

Kernel Setup

Linux Kernel Configuration:
Networking  --->
    Wireless  --->
        [*] Wireless extensions
        <*> Generic IEEE 802.11 Networking Stack (DEPRECATED)
        <*>   IEEE 802.11 WEP encryption (802.1x)
        <*>   IEEE 802.11i CCMP support
        <*>   IEEE 802.11i TKIP encryption
Device Drivers  --->
    Generic Driver Options  --->
        [*] Userspace firmware loading support
    [*] Network device support  --->
        Wireless LAN  --->
            [*] Wireless LAN (IEEE 802.11)
            It is highly recommend to compile the driver as module, see below
            <M>   Intel PRO/Wireless 2100 Network Connection
[*] Cryptographic API  --->
    --- Cryptographic API
    <*>   Cryptographic algorithm manager
    <*>   SHA1 digest algorithm
    <*>   SHA224 and SHA256 digest algorithm
    <*>   ECB support
    <*>   CBC support
    <*>   PCBC support
    <*>   AES cipher algorithms
    <*>   ARC4 cipher algorithm
    <*>   Michael MIC keyed digest algorithm

Because there is no easy way to add the firmware at kernel boot time, the driver gets initalized without firmware. So it is highly recommend to compile the driver as module and let udev automatically load the driver at init boot time. For more informations see this bug report.

Software Setup

Install the firmware: ipw2100-firmware:

# emerge -a ipw2100-firmware

For further configuration follow the Gentoo Handbook.

Advanced Topics

Ensure that your wireless transmitter/receiver is on

If can't get a connection, check the status of the radio kill switch:

# cat /sys/bus/pci/drivers/ipw2100/*/rf_kill

And here, what the status means:

0 = RF kill not enabled (radio on)
1 = SW based RF kill active (radio off)
2 = HW based RF kill active (radio off)
3 = Both HW and SW RF kill active (radio off)

Check the Laptop Table on how to toggle the transmitter state.

Power Management

The driver supports the following different modes:

off     No power management.  Radio is always on.
on      Automatic power management
1-5     Different levels of power management. The higher the number the greater the
        power savings, but with an impact to packet latencies.

Power management works by powering down the radio after a certain interval of time has passed where no packets are passed through the radio. Once powered down, the radio remains in that state for a given period of time. For higher power savings, the interval between last packet processed to sleep is shorter and the sleep period is longer.

When the radio is asleep, the access point sending data to the station must buffer packets at the AP until the station wakes up and requests any buffered packets. If you have an AP that does not correctly support the PSP protocol you may experience packet loss or very poor performance while power management is enabled. If this is the case, you will need to try and find a firmware update for your AP, or disable power management (via iwconfig eth1 power off).

To configure the power level on the IPW2100 you use a combination of iwconfig and iwpriv. iwconfig is used to turn power management on, off and set it to auto.

iwconfig eth1 power off    Disables radio power down
iwconfig eth1 power on     Enables radio power management to last set level (defaults to AUTO)
iwpriv eth1 set_power 0    Sets power level to AUTO and enables power management if not previously enabled.
iwpriv eth1 set_power 1-5  Set the power level as specified, enabling power management if not previously enabled.

You can view the current power level setting via:

# iwpriv eth1 get_power

It will return the current period or timeout that is configured as a string in the form of xxxx/yyyy (z) where xxxx is the timeout interval (amount of time after packet processing), yyyy is the period to sleep (amount of time to wait before powering the radio and querying the access point for buffered packets), and z is the 'power level'. If power management is turned off the xxxx/yyyy will be replaced with 'off' -- the level reported will be the active level if iwconfig eth1 power on is invoked.


Retrieved from ""

Last modified: Sat, 23 Aug 2008 09:56:00 +0000 Hits: 31,569