Raising the Speed Limit with 802.11g Wireless Networking and Windows XP
Published: October 13, 2003
By Barb Bowman, Windows XP Expert Zone Community Columnist
Editor's Note: Past articles by members of the online community are archived for your use. The information may become outdated as technology changes. For the most current information, please search the Web site or post a question in the newsgroups.
I discovered wireless networking early in 1999. At the bleeding edge for its time, the 2 Mbps 802.11 gear freed me from a tethered life style. I was lucky the signal made it from my third-floor home office to my living room sofa. That whopping 30 feet distance degraded the throughput to under 1 Mbps, which was slower than my 1.5 Mbps cable modem connection. The hardware offered no security, no encryption, and no way to change the access point name or channel. And I needed an arsenal of temperamental proprietary software to make it all work. Fortunately, there were no other wireless users within a 50 mile radius.
Later that year, I received my first 802.11b gear and experienced really fast wireless networking. But it was expensive, lacked implemented security, and needed proprietary software to control a wireless network running Windows 2000 or earlier versions of Windows.
Wireless Auto Configuration, the built-in Windows XP feature enabled by the Wireless Zero Configuration service, helped spread 802.11 connectivity. Wireless networking has now reached its prime. It's everywhere from McDonalds to Borders bookstores. Wireless is starting to appear in consumer home theater components and will soon be standard equipment. With the ratification of the fast new 802.11g 54 Mbps standard, wireless networking reaches the speed of wired LANs. There's more good news: 802.11g can co-exist and is backward compatible with existing 802.11b wireless networking equipment.
Read about my experiences with wireless networking in earlier Expert Zone columns, among them: Addicted to the Wonders of 802.11b, Unplugged and Unwired, Securing SOHO Wireless Residential LANS, and Wireless Choices. For links to wireless community sites and more information about wireless networking, see Focus On: Wireless Networking and Windows XP.
In this column, I'll discuss the new 802.11g standard and recommend equipment to consider when building a wireless network. And I'll share two cool ways I use 802.11g wireless networking, which include streaming recorded TV shows over a wireless network and connecting my Xbox wirelessly. For the technical details about the 802.11g standard, read my Overview of 802.11g.
Interoperability among Vendors
I've been using 802.11g wireless hardware from several vendors, including Buffalo Technology and D-Link Systems on a mix and match basis. (I have several independent networks in my lab and can run multiple broadband connections.) Because 802.11g is a standard, wireless hardware that meets the ratified specification will work across product lines from different vendors and you'll be able to combine them to meet your needs.
Before configuring new 802.11g hardware and setting up your network, check for firmware and/or driver updates and apply/install them. Many of the products may not have the full functionality or features expected until they are upgraded. Use a wired connection to perform upgrades.
Broadcom's chips power the 802.11g hardware I received from Buffalo Technology. Broadcom won the 802.11g race, and vendors who are using the 54g chipset were first to market with 802.11g products that support the IEEE-ratified 802.11g standard as well as WPA. Wi-Fi Protected Access (WPA) is the new wireless security specification. See my column, WPA Wireless Security for Home Networks, for more information.
Buffalo has issued firmware to support packet bursting in their router, but it is not yet available in the client adapters or Compact Repeater Bridge. The Buffalo hardware on my network includes a WBR-G54 router, a WLI-CB-G54A PC Card, and a WLA2-G54 repeater bridge.
I've set up a large home office network using tri-mode Atheros 802.11a/b/g hardware from D-Link. D-Link has updated their DI-774 tri-mode wireless router and DI-7000 tri-mode wireless access point to the approved IEEE final 802.11g standard. They've recently added a WPA firmware update for the DI-774 and promise WPA for the DI-7000 soon. The DWL-AG650 tri-mode PC Card supports both the 802.11g final standard and WPA on the 802.11g side.
A separate network is running D-Link's Atheros-based 802.11g only DI-624 (hardware version B) router and DWL-G650 (hardware version B) PC Card. D-Link has just released a firmware upgrade for the DI-624 B versions that supports WPA and brings it to full 802.11g compliance. The D-Link DWL-G650 B version PC Card supports both the final 802.11g standard and WPA.
D-Link, like many other vendors, used Intersil chips in the first hardware versions of these products, but has since switched to Atheros. There's no sign of Intersil upgrades for WPA from vendors using the PRISM GT chipset. Intersil left the Wi-Fi business and sold its PRISM wireless division to GlobespanVirata. So it's unclear if these upgrades will be available from any of the vendors who initially used Intersil solutions. I recently asked GlobespanVirata when consumers could expect WPA drivers from vendors. The GlobespanVirata marketing page for the PRISM GT 802.11g chipset mentions 802.11g certification. Although they provided me with a reference GT card and base drivers that support WPA and the released 802.11g standard, customized vendor-specific drivers for consumer hardware do not appear to be available.
Microsoft Broadband Wireless G Hardware
To complete my roundup of 802.11g equipment, I've recently been working with the Microsoft Broadband Wireless G hardware powered by Broadcom's 802.11g chipset. My Microsoft hardware includes a MN-700 Base Station, a MN-720 notebook PC Card, and a MN-730 PCI Card that has been powering a Windows XP Media Center Edition PC. Fully certified for 802.11g and WPA, this gear is targeted specifically at home or SOHO users in environments that don't use authentication servers and RADIUS. As you can see in Figure 1, WPA-PSK and WEP are both available. Note the user-friendly simplified wireless security configuration screen. The best software wizard I've ever seen makes setting up this gear a breeze.
Figure 1
Secure Your Wireless Network on Windows XP
All of the PC Card wireless client adapters from Microsoft, Buffalo, and D-Link work flawlessly with the Wireless Auto Configuration in Windows XP. On routers and access points that support 802.11g WPA security, the client adapters also worked flawlessly. A WPA-PSK passphrase generates the same initial key for all vendors. Read more about WPA-PSK in my last column, WPA Wireless Security for Home Networks. Also check the Wireless Broadband Security article.
If WPA isn't available, you should use WEP to secure your network. In the past, pass phrase generators for WEP, which were not standardized, wreaked havoc on connectivity when hardware from multiple vendors was used. In many cases when using WEP, the same passphrase generated different hexadecimal keys. Fortunately, Microsoft, Buffalo, and D-Link avoid that embarrassment by requiring the end user to enter the keys manually when WEP is used.
When you are specifying and entering hexadecimal keys, be sure to select only 128-bit encryption. Although higher encryption may be offered by the vendor, Windows XP Wireless Auto Configuration does not support it. When entering the key manually, use only the letters A-F and the numbers 0-9.
In Figure 2, taken from the D-Link DI-774, I've specified a 128 bit hexadecimal key for the 802.11g side of tri-mode router. (I've specified a different 128 bit hexadecimal key on the 802.11a side.) Key 1 will correspond automatically to the hexadecimal key I configured in Windows XP SP1.
Figure 2
On my Windows XP SP1-based laptop, I configure this as a preferred network and immediately connect to it by following these steps:
1. | Right-click the wireless network icon in the notification area, and then click View Available Wireless Networks. |
2. | Select the network name, which in this example is coffeebreak. |
3. | Clear the Enable IEEE 802.1x authentication for this network check box, unless you're in an environment with an authentication server. |
4. | Enter the same hexadecimal key that's entered in the router and confirm it by entering it a second time. |
5. | Click Connect. |
Choose the Right Wireless Hardware
If you have 802.11b client adapters and devices on your network, the best upgrade path is to use your existing 802.11b access point to provide an 802.11b-only segment for your network. Many routers can be configured in access point mode as well. This sets the stage for you to purchase new 802.11g hardware and operate it in "g-only" performance mode.
There are advantages to tri-mode a/b/g wireless. Both the 802.11a and the 802.11b/g side provide high data rates but in different frequency bands and don't complete with each other for bandwidth. If you have a few computers in your household or multiple computers in your home office, you could segment traffic between the 802.11a and 802.11b/g portions. Let the kids only have access to the 802.11b/g network and reserve access to 802.11a for you. When you want to copy a large file (or stream video over the wireless LAN at short distances) when the kids are playing a game over the b/g network using 802.11g, the 802.11a side provides you with your own private wireless network.
Stream Video over 802.11g
Breakfast and a movie on a Sunday morning is becoming a habit. I've recorded and saved so many movies on my Windows XP Media Center Edition PC that I've filled a 120 gig FireWire drive plugged into my third floor office MCE machine. Wireless 802.11g provides the high data rates of 802.11a and the superior range of 802.11b. Simply put, 802.11a is great for streaming, but doesn't work as well at greater distances. Even with walls and three floors, streaming over my 802.11g network (which I run in g-only performance mode only) is excellent.
Figure 3
I'm using Windows Media Player 9 Series and the player update on a Windows XP Professional-based laptop to allow it to play back the dvr-ms files created by capturing recorded television on a MCE machine. (The Windows Media Player 9 Series update is available on Microsoft Update if you don't already have it.) It's easy to open the file on the shared FireWire drive over the network. I double-click the file name and Windows XP does the rest because the dvr-ms file type is automatically associated with Windows Media Player 9 Series on the laptop. As an example of interoperability, note that the laptop is using a D-Link DWLG-650 that is connecting through the Buffalo Air Station and the Media Center computer uses the Microsoft MN-730 PCI Card.
WDS and the Xbox Live 802.11g Connection
Many of the vendors offering 802.11g equipment are offering or are planning to offer wireless hardware to connect wired devices such as game consoles to a wireless network. Several of these vendors are promoting multiple uses for 802.11g access points including access point clients and several are offering dedicated wireless gaming devices.
Buffalo and other vendors use a technology called Wireless Distribution System (WDS) to bridge wired devices or LANs over a wireless connection to another wireless device on the same network. Vendors document that you must connect only to their line of products, but this is not totally accurate. However, it's usually easier to configure components if they are from the same manufacturer's product line.
I've been using a very powerful piece of hardware from Buffalo Technology that they call a Compact Repeater Bridge that can bridge wired Ethernet devices such as an Xbox to a wireless LAN, and simultaneously accept wireless client traffic and act as an access point. In Figure 4, note how transparently WDS devices make the connection to Xbox Live. The blue arrow points to the Buffalo Compact Repeater Bridge.
Figure 4
Although Buffalo's device supports WPA when used as an access point, WPA is not supported yet in WDS mode. I've been yearning for higher speed wireless connectivity for my Xbox, but haven't been willing to give up WPA. My solution was to connect two WDS devices to the 802.11g router and use WEP for security on that segment of my network.
I'm currently bridging the Buffalo Compact Repeater Bridge to a Belkin F5D7130. The Belkin access point is plugged in to a port on the Buffalo G router that is running in WPA mode and handles connections from my wireless computers.
Vendor documentation for setting up advanced WDS bridging is unfortunately not as detailed as it needs to be for most home users. The steps (along with some advice) for a successful WDS setup are as follows:
1. | Both devices need to have the same SSID and channel number. (Unlike roaming between access points that requires the same SSID but different channels.) An additional tweak to my WDS network segment was to run both devices in "G Performance mode only" for optimum speed. |
2. | Use static IP addresses for the WDS bridge in the same range as the rest of your network for easy manageability from computers on your LAN. If you purchase hardware from multiple vendors, you'll probably need to change the IP address of the hardware to conform to the range supplied by your router. Although these devices can usually accept a dynamic address via DHCP, a static assignment ensures that it will be easy to connect and change settings if needed. |
3. | Until WPA capability is available in bridged WDS devices, use 128-bit WEP. If you want to retain WPA capability for computers, you'll need to segment the network and use two WDS devices, one of which can be plugged into a wireless router configured for WPA. (In this case, the SSID and channel must be different from those configured on the router.) |
4. | Enter the wireless MAC address of WDS device 1 into the corresponding setup field in device 2. Enter the wireless MAC address of WDS device 2 into the corresponding field in the setup screen for device 1. Buffalo conveniently affixes a sticker with the MAC address to use on the outside of the unit itself. Hardware from other vendors may or may not have the correct wireless MAC address printed on the outside. You will need the wireless MAC address and not the Ethernet MAC address. |
5. | Depending on the vendor, you may be able to turn off the ability for wireless clients to connect through the WDS devices. If wireless computers are using the connection at the same time a gaming console is transmitting, throughput will be impacted.  Figure 5 |
Figure 5 shows how I've configured WDS devices from two vendors with MAC addresses entered and wireless bridging enabled. Since there are no demands for a wireless computer connection when I'm using Xbox Live, wireless computers are allowed to connect to the WDS.
How easy was it to get the Xbox itself online after this configuration process? Using automatic settings on the Xbox, it all happened automagically and in less than five seconds. I wish everything were that easy!
What's Next?
I'm looking forward to fully showcasing the new Microsoft Broadband Networking Wireless G hardware and demonstrating how the best setup wizard on the planet takes all the stress out of configuring a wireless network.
Meanwhile, if you're looking for help configuring the 802.11g gear you own or are looking for opinions from other end users on what 802.11g hardware to purchase, Microsoft offers two newsgroups where you can post your questions and get fast online help: Microsoft Windows XP Network and the Web Newsgroup or the Microsoft Windows Wireless Networking Newsgroup. See you there!
Barb Bowman enjoys sharing her own experiences and insights into today's leading edge technologies. She is a product development manager for Comcast High-Speed Internet, but her views here are strictly personal.
