wirelezz blog

waves're in the air everywhere I look around…

Posts Tagged ‘802.11

[Solved] That Atheros AR9285 WLAN Card Problem

with 15 comments

About six months ago, I bought this awesome Samsung laptop at a great price. It’s been working just great, the only problem has been the WLAN card. It’s an Atheros AR9285 802.11a/b/g/n. At the beginning it worked fine, but lately it’s been failing like mad: it randomly loses connectivity from the WiFi network, although Windows stated otherwise.

I quickly thought it should have been a driver issue, so I looked for one that would do the job, and I found it at HP’s support website. Since it’s just a driver, it wouldn’t be a problem, right?

Here is the driver’s link: It’s for an AR9285 WLAN card running under a 64-bit Windows 7 (be sure to read that)

In case you don’t know how to install it, here’s how to:

  1. Extract its contents and then, under network connections, get in the properties of your wlan card
  2. Click on configure
  3. Then click on driver’s tab and then click on update driver
  4. Now click on Browse my computer for driver software.
  5. Click on the “Let me pick from a list…”
  6. Click on “Have a disk” and then click on browse, and search for the netathr.inf file. Then next.
  7. Select AR9285 802.11a/b/g/n from the list, then next. That should install it.

It works great now. It was just a matter of updating the driver, but looking for the right one is a real pain in the neck. Let me know if it works for you too.

Written by Wirelezz

September 17, 2011 at 2:21 pm

Posted in etc

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What is so great about OpenWRT?

with 3 comments

Lately I’ve been experimenting with OpenWRT, a linux distribution for embedded devices. The great thing about OpenWRT is that you can install it to most of the cheapest WLAN devices, ie. routers (check the table of supported hardware).

I know that most Open Source projects may never be as good as proprietary solutions for real implementations. However, in the particular case of OpenWRT, I have identified three major advantages:

It’s a great tool for research
It’s an awesome tool for researching on many fields such as: protocol design, fast handoff schemes research, WIDS, Wireless mesh networking, and so on. Learning and doing Unix socket programming in C for OpenWRT may give a large number of headaches, but it’s the best way to get the full control of the information sent over the air.

It’s a great study tool
There’s indeed a difference between reading about the 802.11 standard and getting hands-on training equipment -of course, reading is extremely important- but some of the most advanced concepts are not available anywhere but in enterprise solutions. If you don’t have the access to such equipment, you may want to install OpenWRT on your (cheap) Linksys WRT54GL and also install some packages that would do the magic.

For instance, how do you see what is actually going on through a WPA2-Enterprise (with a RADIUS server, EAP/MD5 auth) handshake on both the wired and wireless side? You could install FreeRadius to a linux box to use as authentication server. Sniffing the air is possible by using wireshark or tcpdump in the OpenWRT box.

If you want to learn a little more about WLAN Controllers, you may want to take a look at the ChilliSpot project. You need to install it on both a WRT54G and a Linux box to see it in action.

VLAN segmentation by editing configuration files, deploying a VPN server on the router, wireless mesh networking using different routing protocols, installing Asterisk on the box, etc. There’re A LOT of packages that can be installed.

Save money
It’s as simple as this: you get many of the features only found in (expensive) enterprise solutions by installing a free firmware on a $60 router.

As I said (somewhere) above, OpenWRT may not be suitable for large enterprise implementations (should not), but it’s a great tool for studying the 802.11 standard, researching or just having some fun. I do not recommend it for illegal purposes.

Some useful links:
Installing and configuring OpenWRT Kamikaze
OpenWRT forum
Use FreeRADIUS for Wi-Fi Authentication

The idea of writing this post came up after reading a question asked by @jameyk1stner via Twitter which basically stated: is there any way to practice for the CWNA exam with real scenarios by using real APs, Controllers, etc?.

Written by Wirelezz

August 23, 2010 at 10:15 am

Posted in Uncategorized

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