Proxim WLAN roadmap reveals 802.11's growing pains

Long a staple in enterprise WLANs (along with Cisco's AiroNet), the Orinoco brand of WLAN gear is getting a major refresh from Proxim, the vendor that acquired that brand from Agere last year. While Proxim's emphasis on cost, security, performance, and 802.11 b/a/g coexistence and migration is the sort of strategy that corporate WLAN administrators will welcome, it also draws attention to the growing pains that a maturing technology like WiFi must go through before it's ready for prime time.

According to Proxim solutions marketing director Lynn Lucas, the company is releasing several new WiFi access points as well as some new Cardbus-based cards, all of which will support the yet-to-be ratified 802.11g standard as well as WiFi Protected Access (WPA).

The chief selling proposition of 802.11g is that it operates at the 54 mbps speed of 802.11a without sacrificing compatibility with the slower 802.11b. Both 11g and 11b operate in the 2.4 GHz frequency range, whereas 11a operates in the 5 Ghz range. As a technology, WPA has been hailed as an interim step that WLAN administrators can take to better secure their 802.11-based networks while the IEEE completes its work on the official WLAN security standard--802.11i.

While I hear a lot about "g's" compatibility, what I don't often hear is talk about the sacrifices required to achieve that compatibility. For example, existing access points using a PC Card architecture (as my old Orinoco setup does) may not be enough to get what you're looking for now. When I started using the test gear that has been serving as my WLAN infrastructure, I found the PC Card architecture of the access points to be an unusual design choice. The explanation I was given was that, in case the hubs needed to be upgraded, that this was infinitely better than an integrated radio because I could simply replace the PC Card instead of the entire access point. The access point came with two PC Card slots.

But, as it turned out, the next upgrade steps for my 11b gear were 54 mbps technologies (11a and 11b). According to Proxim's Lucas, a newer access point supporting the higher bandwidth CardBus standard (instead of PC Card) had to be released. Dubbed the AP2000, the dual-lot, CardBus-supporting access point, according to Lucas, is equipped to handle the throughput produced by 54 mbps adapters, whereas its predecessor, the AP1000, was not.

Proxim has also released a downscale AP600 access point that targets branch offices and small businesses. The AP600 has all of the features of the AP2000 but instead of a CardBus architecture, it has an integrated radio that's available in three flavors: a, b, or g. Proxim expects the AP600 to be priced at around $395 for 11b support, $549 for 11a, and $495 for 11g. Why so much more money for 11a? Lucas says pricing on the 11a chipset is higher and that 11a has a different antennae technology that makes 5 GHz deployments more expensive than 2.4 GHz.

As far as compatibility is concerned, Lucas also pointed out one of the caveats to running the AP2000 or the AP600 access points in what's called 802.11g's "mix mode" (the mode where it supports 802.11b and 802.11g at the same time). 11g's mixed-mode, said Lucas, "is great for backwards compatibility, but throughput on the access point won't be as good as if you had a g-only network. With a single radio operating at both speeds to talk to 11 and 54 mbps clients, the access point has to throttle back to talk at the slower speed. As a result, the overall throughput is lower. We spent a lot of time in optimizing the performance for operation in the mixed b/g mode. As a result, we're seeing overall throughput that's 50 percent better than what our competitors Linksys, D-Link, and NetGear are getting in the same mixed mode."

While it was interesting to hear Lucas pitch Proxim's enterprise wares against three decidedly non-enterprise providers, I was more curious about how Proxim believed it was faring against market heavyweight Cisco. "In order to play in the enterprise space, you have to come to market that supports 802.1x security with rotating keys and you have to be WPA-ready," Lucas said. "You can't deploy an 11g product unless you address those concerns and, so far, Cisco hasn't come to market with such a solution."

		Reader Resources Wireless LAN ZDNet White Papers

Cisco is not without a plan, according to a Cisco spokesperson. "We believe that 802.11g is a complementary standard to 11a and that, ultimately, enterprise customers will want dual-band products utilizing 802.11g and 802.11a. That said, the 802.11g standard is still in development and not yet ratified. However, once the 11g standard is finalized, Cisco will be delivering Cisco Aironet Access Points very shortly thereafter. Finally, the Cisco Aironet 1200 and 1100 Series Access Points are already future proofed for this new higher performance standard as they are both field upgradeable to IEEE 802.11g once the standard is finalized."

Proxim's Lucas, however, isn't concerned about releasing product before the standard is finished. Said Lucas: "While 11g is not 100 percent ratified, it is technically nailed down. Our products will comply 100 percent with the 802.11g specification." In addition to bringing to market a series of products that support a yet-to-be ratified standard, and securely so, Lucas claimed that the AP2000 and AP600 will automatically do load balancing to make sure that one access point doesn't get too heavily overloaded. "The access points have user-settable thresholds. If too many people attach to one access point's channel and are overloading it, then it boots the next user that auto selects it and moves that user to the next access point. The access points sense whether other access points are close to them and which ones are closer than others."

But this isn't necessarily a great idea. For example, using the face of a clock as a site map, imagine if a user sitting at 9 o'clock attempts to connect to an access point located at the clock's dead center. But let's say that the additional connection causes the access point's user-settable thresholds to be exceeded and the access point boots the user to the nearest access point, which happens to be sitting at 3 o'clock. But what if the access point sitting at 3 o'clock is too far away from the user sitting at 9 o'clock to get an acceptable signal? Shouldn't the two access points work together to figure out if there's a more ideal user --- maybe one that's geographically situated between them --- to bump to the 3 o'clock access point, thereby making room for the 9 o'clock user to connect to the access point in the middle of the clock face?

Lucas said that Proxim plans to introduce a switch-based platform called Maestro that should be up to the task of intelligently allocating mobile users to the access points that best accommodate connectivity for all.

As part of our year long Wireless that Works special report, we want to hear your tales from the frontier that highlight the successes and failures of wireless technology deployments. To have your company considered for a "Wireless that Works" case study profile on ZDNet, send us an e-mail. We need the name, phone number, and e-mail address of a business contact at the company, and ideally a technical contact as well.

Are you dialing in a migration strategy while so many things are in flux, or are you moving forward with 11g-based WLAN deployments. . Share your WLAN dreams and nightmares with your fellow ZDNet readers , or write to me at david.berlind@cnet.com. If you're looking for my commentaries on other IT topics, check the archives.