Last August we wrote about the joys and sorrows of installing Apple's AirPort Express on our existing home network (Part 1, Part 2). At the time, I promised an update on installing Wi-Fi Protected Access, since the AirPort Express didn't get along with Wired Equivalent Privacy, and the home security chief (my wife) didn't want a totally unsecured wireless network.

Several months have passed, and we’ve been able to stay unsecure without retribution - meaning the neighbors haven’t yet started trying to steal our wireless access. 

But when Santa brought us an iBook G4 notebook, we decided the Christmas break would be a great time to install WPA, as well as integrate the Apple system into our Windows-only network.

Our first step was to re-configure the wireless router (a four-port Linksys 802.11g) to use WPA. Changing the wireless security settings wasn’t difficult; the router let me choose between WPA Pre-Shared Key or WPA RADIUS authentication, and since I don't have a home RADIUS server I chose the former.  

The Linksys router also lets you choose Temporal Key Integrity Protocol (TKIP) or Advanced Encryption Standard (AES) as the encryption method. A quick trip to the Linksys Web site revealed that "TKIP uses a strong encryption method that adds a Message Integrity Code for added protection," while "AES uses a symmetric 128-bit block for data encryption." Added protection won out, so we chose TKIP.

My next step was to configure the AirPort settings on the iBook. To my dismay, Apple doesn't let you choose WPA-PSK. Rather, your choices are "WPA Personal" or "WPA Enterprise." I chose Personal, as I knew WPA-PSK was recommended for home use. Too bad Apple and Linksys can’t get together and use the same terms.

Next I was off to configure two Windows XP notebooks. The first used an 802.11g Linksys PC Card and configured somewhat easily - but only after I disabled the Windows XP settings and let the Linksys utility do the heavy lifting.

However, my second notebook used an older 802.11b card that didn’t support WPA. Not thinking and surrounded with equipment, I decided to disable WPA and move the notebooks back down to WEP. After some head scratching, I wasn't sure why the AirPort Express wouldn’t work, then I remembered it has problems working with WEP. That was the whole point of upgrading to WPA! Gaahh.