NETGEAR WAG511 Dual Band Wireless PC Card Reviewed

Introduction

The draft-11g market has moved quickly, progressing through the first generation of single-band b/g products to the second generation dual-band, tri-mode products in a matter of months. NETGEAR’s WAG511 was one of the first tri-mode wireless CardBus adapters available, so it made its way to the head of my “must review” list. I was generally pleased with the results of my testing.

Features

The 511 is based on Atheros’ AR5001X+ “Combo” WLAN chipset. This is essentially the same chipset used in NETGEAR’s WAB501 802.11a/b adapter (and pretty much all 802.11a/b Cardbus adapter products), but with an AR5212 Multiprotocol MAC/baseband processor instead of the AR5211 chip used in the dual-mode WAB501. Figure 1 shows an internal view of the card.

Figure 1: The innards

Contrary to some reports, Atheros-based dual-band 802.11a/b CardBus adapters cannot be flash-upgraded to tri-mode a/b/g operation, because the 5212 chip is needed to provide the “secret sauce” for 802.11g.

Nor does using the WAG511’s driver with a WAB501 (or any other Atheros-based 802.11a/b card) make it operate as a tri-mode adapter. You can, however, use the WAG511’s utility with a WAB501 card, although the utility will identify the WAB501 as a WAG511 on the utility’s About tab.

Tip: I previously had installed a WAB501 in my test notebook and found that I had to go to XP’s Add / Remove Programs utility and uninstall the WAB501 in order to get the WAG511 to install properly.

Eagle-eyed buyers of the WAG511 may notice that it has the same FCC ID as the WAB501. At first I thought this might just be a mis-print, but then started to think that the conspiracy theorists might be right – that the WAG511 is just a re-labeled WAB501! A quick check with NETGEAR, however, brought the answer that the MAC/baseband chip substitution described above is considered a “permissive change” in FCC jargon. This allows the same FCC ID to be used – saving the expense and delay of submitting the modified design for a new round of testing.

Similar to its 802.11a/b sibling, the 511 requires a CardBus, not a PC Card slot. This is because CardBus is a faster 32 bit bus vs. the slower 16 bit PC Card standard and is needed to support the card’s higher data rates.

Tip: Since CardBus and PC Card products look virtually the same, you’ll need to check your laptop’s PCMCIA Adapter entry in Windows’ Device Manager to see whether your machine supports CardBus. Proxim has a handy CardBus FAQ (PDF format) if you need more info.

The adapter has two LEDs, which blink in unison most of the time, with rates varying according to network activity. You get an alternating blink pattern when the card is searching for an Access Point or other AdHoc client (when in AdHoc mode, of course). The LEDs are at the end of the fairly large antenna housing which will block the CardBus slot above it in a multiple slot laptop. The card has no provision for attaching an external antenna.

Setup and Administration

The install went smoothly into my Dell Inspiron 4100 notebook running WinXP Home. I liked the STOP WINDOWS XP USERS PLEASE READ FIRST! card that topped the documentation pack and provided the usual instructions to ignore XP’s Driver Certification warning. I would also have added an “Install the Software before plugging in the card” warning, since there’s no Quick Install sheet provided, and you have to actually read the printed User’s Guide that NETGEAR provides to pick up this important piece of information.

At any rate, I ran the install from the CD, popped in the card and everything went smoothly. Since XP has built-in wireless networking features, but isn’t set up to handle dual-band tri-mode cards, I was glad to see that NETGEAR’s utility and XP knew how to stay out of each other’s way. If XP’s “Zero Config” feature is enabled, NETGEAR’s utility hides all its configuration controls and just displays its Status, Statistics and About tabs. Unchecking the “Use Windows to configure my wireless network settings” checkbox on XP’s Network Connections Properties > Wireless Networks tab restores all the NETGEAR utility tabs. I unchecked the box and used the utility for all my interactions with the adapter.

Figure 2 shows the Status tab of the utility, which is pretty much self-explanatory.

Figure 2: Status Tab

I still wish that the Signal Strength indication were in dBm and that a Signal to Noise indication in dB were provided instead of the % Signal Strength indication. Yeah, I know it may confuse some users, but wireless networkers have had to learn plenty of other jargon, so why not? I suspect the real reason for the qualitative indicator is to make it harder to do performance comparisons!

I also think that the signal level / quality, and connection speed should be reflected in the “ToolTip” that appears when you put your mouse pointer over the System Notification (System Tray) icon. That’s one area where the XP Network connection icon is better, since it shows both connection Transmit rate and Signal Strength.

Setup and Administration, Continued

Figure 3 shows the utility’s Configuration tab, which gives you access to most of what you’d need to configure the card, and is where most of the action is.

Figure 3: Configuration Tab

This tab is improved from the WAB501’s utility, with Profiles moved to their own tab and a cleaner layout. The main functional improvement is the addition of the ANY (First Available Access Point) option to the Network SSID pick list. This basically mimics WinXP’s Zero Config and should make it easier to roam among differently named networks. SSID’s picked up in the Site Survey tab are automatically copied into the pick list, too.

You also get a choice of Normal or Maximum for Power Savings, Auto and Long Only for 2.4GHz preamble, and Transmit Power settings of 100,50,25, 12.5, and lowest. I’m still unconvinced of the value of the ability to reduce a wireless client’s Transmit power, but if you want to mess with it, it’s there.

I continue to be disappointed with the Radio Band Control options provided in Atheros-based multi-band products, and this latest version of their client app seems to have taken a step backwards. It allows only the simple selection of 802.11a, 11a “Turbo”, and 11b/draft-11g modes, and omits the Auto mode provided in the previous version.

I would have liked to see the ability to force the card to 11b-only operation, but more importantly more options for controlling the tri-mode nature of the card. I had hoped that there would be some sort of “best-connection”, or “best-throughput” modes, or even the ability to specify a preferred network mode, i.e. a, b, or draft-11g. And what’s the use of having multiple Connection Profiles (shown in Figure 4), if you can’t specify which ones are preferred, and in what order? Even XP’s Zero Config lets you do this, although they haven’t yet admitted the existence of 11a and now draft-11g WLANs!

Figure 4: Profile Tab

Setup and Administration, Continued

Figure 5 shows the Security tab, which is pretty standard stuff.

Figure 5: Security Tab

This newer client now lets you enter four keys directly in Hexadecimal characters, or you can generate the keys automatically via an alphanumeric passphrase. 64, 128, and 152 bit key lengths are supported with the keys not stored in cleartext, but maintained when you disable, then re-enable WEP. Unfortunately, you can’t write or read the keys to/from a file, but at least the utility prevents you from entering a key longer than the allowable length for the level of WEP you select. Note that the client utility doesn’t yet support the impending WPA security enhancement.

The Site Survey tab (not shown) is similar in function to XP’s Wireless Connection Properties > Wireless Networks tab, and shows all Access Points / Wireless routers and AdHoc stations within range. It also lets you select an Access Point and click a Connect button to get hooked up without having to switch over to the Configuration tab.

Although a Re-Scan button is provided, a real Site Survey function would have been more like the throughput plots provided on the Statistics tab (Figure 6), but with plots of signal, noise, and SNR over time for selected APs. Barring that, I’d like to be able to start and stop a continuous scan for new APs, and, of course, control the scan interval. It would also have been nice if the Signal numbers on this tab matched the Signal Strength indication on the Status tab, too.

Figure 6: Statistics Tab

The Statistics tab provides plots of Transmit and Receive data rates that are updated each second, but can’t be saved or cleared.

In all, this new client has some nice improvements over the older dual-band dual-mode client, but has a ways to go before it really provides the control required for a tri-mode, dual-band operation.

Performance tests are next!

Wireless Performance

Since NETGEAR is holding off on shipping their tri-mode AP and router, I had to make do with a combination of their WAB102 802.11a/b and WG602 draft-11g [reviewed here] Access Points to put the WAG511 through its paces. Since the table below shows a summary of the draft-11g test results, I’ll start there.

The draft-11g performance seems to provide the best combination of speed and range in my residential test environment. The table shows surprisingly consistent performance in three of my test locations, with performance degrading slightly at my longest range test point. Figure 7 shows the results from my Chariot tests.

Figure 7 : Draft-11g throughput

(click on the image for a full-sized view)

Although the plots are a little tough to make out, I think you can get the general picture. I also ran a throughput check with WEP enabled, which is shown in Figure 8.

Figure 8: With and without WEP

(click on the image for a full-sized view)

The difference between average throughputs is only about 4%, which I say is close enough and probably within the accuracy of my measurements.

The WAG511’s performance is definitely superior to that of the NETGEAR’s Intersil-based WG511 single-band draft-11g card, shown in Figure 9.

Figure 9: Four Condition Throughput – NETGEAR WG511 and WG602

(click on the image for a full-sized view)

This is the plot from the WG602 review, where I used the same WG602, with the same 1.04.00 firmware. I think the results speak for themselves.

How many AP’s does it take to test a tri-mode card?

I expected the WAG511 to have the same superior 802.11b performance as Atheros’ dual-mode (a/b) design, but had a hard time proving it with the Access Points that I initially used for my testing. I found the WAB102’s 11b radio to be, frankly, awful, as you can see in Figure 10.

Figure 10: 11b throughput with WAB102 AP

(click on the image for a full-sized view)

You see only three traces in the plot because I couldn’t get a signal at my Condition 4 worst-case location. Given the excellent performance of the Atheros 11b radio in previous testing, I can only say that the WAB102’s 11b radio must be particularly bad to cause the WAG511 to not be able to get a signal. I shared my findings with NETGEAR, who sent me a soon-to-be-released WAB102 firmware update that they said should improve performance, but didn’t.

My next attempt at 11b mode testing was with the WG602. Since it has no mode controls, I tried forcing its transmit rate to 11Mbps in hopes that it would get the hint. But since the WAG511 client (and my throughput test results) showed that it was transmitting at 11g rates, I had to abandon that approach.

I finally grabbed an SMC2655W 11b AP and did a quick set of Chariot runs, which as Figure 11 shows, proved my expectations of the WAG511’s excellent 11b radio.

Figure 11: 11b throughput with SMC2655W AP

(click on the image for a full-sized view)

One more mode left, and then the wrap up.

802.11g Wireless Performance Test Results

See details of how we test.

Performance – 802.11a

The WAG511’s 11a throughput was surprisingly good, with Figure 12 showing much better performance than I’ve previously had with any 11a products.

Figure 12: 802.11a throughput

(click on the image for a full-sized view)

Figure 13: WEP and Turbo mode performance

(click on the image for a full-sized view)

I also ran tests in Turbo mode, and with WEP enabled in both normal and Turbo modes. Figure 13 shows an average throughput of about 31Mbps in Turbo mode under best case conditions. I also ran tests at all four of my test locations and found that, unlike my previous tests, Turbo mode still produced an approximately 40% throughput increase even under weaker signal conditions. You can also see that WEP-enabled performance is virtually identical to running without it.

In all, a very impressive performance in all modes.

802.11a Wireless Performance Test Results

See details of how we test.

Wrap Up

The wireless standards wars are over folks, and the winner is 802.11a, 11b and draft-11g! In other words, dual-band tri-mode cards and APs are going to make which standard you use a moot point. Just as with cellular service, a tri-mode card will let you use whatever mode is available, with the only difference being how fast you connect, instead of the voice quality of a phone call.

NETGEAR’s WAG511 is a strong entry into what will be a very crowded field that, this time, won’t be automatically filled by clones of the same basic reference design. Last time Atheros had the 11a and a / b market all to itself. This time, they’ll have to earn their market share from very aggressive competitors.

For now, however, the WAG511 will be replacing the WAB501 as my WLAN card of choice. But whether it remains there is up to its competitors. So if ya got what it takes, guys… bring it on!

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