Get Belkin F5D7632uk wireless G modem working in Linux

Q I have recently installed Fedora in dual-boot mode on my HP Pavilion t3065 (Intel Pentium 4 3.4GHz with 1GB of RAM). All went well until I tried to connect to my Belkin wireless G modem (802.11g - model F5D7632uk ver 1000), and it was only after much head scratching and searching on the internet that I discovered I needed a wireless driver. Having interrogated my network controller, I found that my chipset is as follows :

Intersil Corporation ISL3890 [Prism GT/Prism Duette] / ISL3886 [Prism Javelin/Prism Xbow] (rev 01).
Subsystem: Accton Technology Corporation WN4201B.
Flags: bus master, medium devsel, latency 64, IRQ169.
Memory at cfffc000 (32 bit, non-prefetchable) Size 8k.
Capabilities: (dc) Power management version 1.

Having had a look at various sources on the web on the subject of connectivity with this chipset (including www.prism54.org), I am now confused. Do I need a FullMAC driver or an Islsm driver? The listed drivers cover one or the other ISL variant but not both together! This begs the question: does it matter which one I choose? Assuming that I can get Linux to talk to my wireless modem, does Fedora or any other distro support WPA-PSK security, or is 128-bit encryption the best that is on offer for now? How would I go about implementing WPA-PSK on my PC?

A A few years ago, Prism released a new version of its chipset that offloaded some of the work to the host computer (in other words, it was a cheaper, half-complete design rather like a Winmodem). This became known as the SoftMAC design, and it broke compatibility with the Prism54 drivers until the Islsm drivers were developed. The Islsm driver works with both SoftMAC and the original FullMAC chips. The FullMAC driver works better with FullMAC devices, but not at all with SoftMAC ones. Unfortunately, it is difficult to tell which you have - the ISL3890 works with the FullMAC driver but the ISL3886 needs Islsm. The FullMAC driver is built into the standard kernel for Fedora; you only need to install the firmware file, which can be downloaded from http://prism54.org/fullmac.html. You can test it by opening a terminal and typing

su
(give root password when asked)
modprobe prism54
lsmod | grep prism54

If the final command gives an output, the driver is present and loaded - so try to connect to your modem. You should disable all encryption (WEP and WPA) while testing at first - get the connection working then sort out the encryption (until it works you have nothing to encrypt anyway). If the Prism54 driver fails to connect, try the Islsm driver. This also needs a firmware file, but a different one, which you can get from http://prism54.org/newdrivers.html. Comprehensive installation instructions are included in the package. WPA-PSK encryption is available for Linux, in the form of wpa_supplicant (http://hostap.epitest.fi/wpa_supplicant). Fedora includes packages for this - you need to install wpa_supplicant and wpa_supplicant-gui. Only the first is essential, but the second provides a GUI for configuration, which saves reading and editing configuration files.

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