Jacek Pliszka's wireless hints: 802.11b / Wi-Fi Linux USB

Jeśli znasz polski to możesz zajrzeć tutaj - jest to FAQ opisujący sieci bezprzewodowe (Wi-Fi).

Things that have moved to separate pages

  1. How to get running Prism2 802.11b devices with linux-wlan driver (example for Linksys WUSB11 v2.5 USB adapter)
  2. Information about ATMEL AT76C503A devices - most USB cards are of this type
  3. Information about AT76C510 based APs
  4. Information about TI ACX100 devices

Contents

  1. Short description of a few 802.11b devices
  2. 802.11b drivers for Linux
  3. USB 802.11b devices under Linux - drivers, how to identify your hardware etc.

Sveasoft +shaper and frottle http://www.pbs.org/cringely/pulpit/pulpit20040527.html

PrismGT drivers - now they even have Master mode working (AP mode)

Linux and Wireless LANs

OS NDIS wrapper allowing to use Windows drivers in Linux

There is also a similar one but commercial made by Linuxant.

Driver for 802.11G Prism chipsets

MADWIFI 802.11a/b/g Linux driver for Atheros devices

Short devices description

I use connector definitions from: http://www.hyperlinktech.com they have photos of all the types! You can find a large table with different devices here. Below is a list of devices I or a person I know tried. Careful! RP means reversed sex!

Access points (some of them work as clients)

USB cards

Most of them are based on ATMEL AT76C503A - if you do not find your card below, see the link at the top for Linux drivers. Another popular chipset is Prism2 - also see another link at the top of this page for information about running these cards under Linux.

PCMCIA cards

CompactFlash (CF, Compact Flash ) cards

PCI/ISA cards

Dedicated 802.11b - Ethernet bridges

These are dedicated devices working as clients which allow to connect you one or more machines connected to them through Ethernet port to briode to a distant wireless network. They are not that popular as many APs (like mentioned above AT76C510 or TI ACX100 based ones or OpenAP) have this feature. The distinction is that unlike many APs you can run them in AdHoc mode and then they are able to both bridge and repeat !!! To be more precise, when you have Lan1--B1...B2--LAN2 tow LANs connected with bridges B1 and B@ (dots is for wireless, minuses for ethernet) then if you run B1 and B2 in AdHoc mode you can connect AdHoc mode wireless clients to both B1 and B2 !!! Ones I know are: Linksys WET11, D-link DWL-810/DWL-801+,Hawking WB320

802.11g products

Looks like first 802.11g Linux drivers start to appear, this time for Intersil Prism GT/Indigo/Duette chipset, more infor see here: http://ruslug.rutgers.edu/~mcgrof/802.11g/ I do not know about drivers for other 802.11g chipsets. But so far for me 11mbps is enough since my cable is 256kbps.

Amplifiers

I;ve seen just cheap Linksys WSB24. Not much use as it has 100mW - same as many APs. USA version has 110-120V.

Drivers for 802.11b for Linux

First read Linux Wireless HOWTO

My page how to set up linux-wlan-ng driver Red Hat Linux (may be useful for ohers as well).

My page (obsolete - see link on the page for more info ) about drivers for AT76C503A devices.

AP on Linux with Prism2 card

I made a sperate page about it here

802.11b USB devices under Linux and some general hints for linux-wlan driver(useful also for non-USB devices)

First you may want to look at linux-wlan FAQ. Second you may want to read my general info about USB and module compilation here

For status see for example www.qbik.ch and www.linux-wlan.org (bottom of the page). Also you may look at Intersil web page. Also look inside the prism2sta.c file in the most current release o the drivers and look through records in usb_id_tbl table. Generic info is such that working devices are: Linksys WUSB11 v2.5, Actiontec HWU01170-01, Siemens SpeedStream 1022 and Compaq Evo N600C multiport (not Compaq iPaq!!!) - see for info about them below - even if my setup describes inksys WUSB11 v2.5 - setup for other cards supported by linux-wlan is very similar. For devices based on AT76C503A see here.

Wireless soft under Linux
Apart from dirvers above I know about:
  1. korinoco for ORINOCO cards
  2. some soft for AT76C510
  3. Wi-Find
  4. Kismet
  5. Wellenreiter
How to tell your hardware
  1. Check the above site (linux-wlan,atmel drivers site, qbik etc.) for yours. If your is not there - compare VendorId and ProductId as most vendors do not change them. VendorId and ProductId can be read by usbview,lsusb or from /proc/bus/usb/devices, /var/log/messages or from dmesg output
  2. search web for your device
  3. look inside windows drivers - download them install/unpack (someitmes you can do it with wine) and look inside. They often have something like AT76C503A or similar thing inside.
  4. go to FCC webpage and look at photos/description of your device. Alternatively you can use FCC ID with this form. On internal photos - look for chips specs. On external photos - compare them to photos of well known devices (almost all ORINOCO-based devices look the same even if branded by different companies like HP).
  5. ask on the discussion lists/newsgroups (linux-wlan,BAWUG etc.) - remember to search their archives first!!!!
  6. try adding your ProductId and VendorID to linux-wlan driver - maybe it will work
  7. void warranty and dissassemble it

General debugging

  1. Start with putting your devices next to each otehr
  2. Be patient, sometimes some things take a minute or two
  3. When resetting - remember, som devices require the reset button to be pressed for couple of seconds - read the manual
  4. Ensure the hardware you bought can do the things you imagine, it is common for our imagination to surpass the reality
  5. Use static IPs first - at leas you will know it is not DHCP problem
  6. Make notes - write down what you enteres in what, pick SSID you can be sure it is unique, if you stick with default - some day your neighbour may have it too!!
  7. Start with most "forgiving" configuration: "Open System", no WEP
  8. Set same options like preamble (more common is long)
  9. if you can not get the signal - ensure there is no metal or other obstruction between (even steel rods in the walls, if dense enough can stop the signal completely), also try to move yoru antennas and change their orientation

Security

to be written: WEP, SSH, VPN, MAC filtering
Jacek Pliszka
Last modified: Fri Mar 19 15:08:36 CET 2004