Wireless LAN technology is nothing new. But something different is happening in the wireless industry this year. Vendors across the board are shipping truly interoperable hardware that delivers data rates approaching those of Ethernet. The wireless industry is finally gaining some momentum in the enterprise market. Perhaps it's due to lighter, more portable notebooks. Perhaps it's because of WECA, the Wireless Ethernet Compatibility Alliance (www.weca.net), a highly active group of vendors with a mission to guarantee interoperability across all 802.11b products. Or maybe it's attributable to the broadband revolution, which is enabling Wayport and others to provide low-cost 802.11b connectivity to many hotels and airports. By far, the most compelling reasons are interoperability, cost and performance. Vendors have made quantum leaps in all three areas, making wireless LANs a viable technology for the masses.

Whatever the reason, vendors are embracing and investing in 802.11b high-speed wireless LANs. With Cisco Systems' recent acquisition of Aironet, all the major enterprise infrastructure providers--Cisco, Enterasys Networks, Lucent Technologies and Nortel Networks--have a wireless story to sell. Never before has there been such a strong backing of wireless technology. Is it time for you to consider a wireless solution?

In the Schneider National labs in Green Bay, Wis., we tested 802.11 high-rate (802.11b) wireless solutions from 11 vendors. We evaluated products from BreezeCom, Cisco, Compaq Computer Corp., Enterasys, Farallon Communications, Intermec Technologies, Lucent, NoWires Needed, 3Com Corp., Zcomax Technologies and Zoom Telephonics. We also tested products that are designed to coexist in an 802.11b environment (see "Top Ten Things To Know About Wireless.")

Cisco's Cisco Aironet 340 Series PCI Adapter (AIR-PCI342) and Cisco Aironet 340 Series PC Card (AIR-PCM342) led the pack, with raw throughput under Microsoft Windows 98 topping out at almost 6 Mbps--not bad for 11-Mbps wireless solutions. We were also impressed by Cisco's access-point solution, the Cisco Aironet 340 Series Access Point (AIR-AP342E2C), which earned top marks for manageability and ease of use.

Wireless Scalability

The ability to scale the amount of bandwidth and the number of users your wireless LAN can support is critical. Specifically, most vendors claim they can support 65 users or more per wireless LAN segment. But what effects do multiple wireless users have on segments? We did extensive testing to find out how well the technology scales. To test different aspects of scalability, we used three wireless clients and 12 workstations to generate our traffic load. We tested in three configurations: three notebooks associated to a single access point; three notebooks associated to three access points using the same frequencies but different network IDs; and three notebooks associated to three different access points, all using different frequencies. These configurations show how wireless scales in a single access-point environment, a multiple access-point environment and a multichannel, multiple access-point environment.

Our tests revealed a few important facts about 802.11b. A single PC Card can saturate a wireless segment. Whether you have one user or 50 on a segment, they will contend for the same amount of bandwidth. After all, this is a CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) network, and like shared Ethernet, this shared network has a finite capacity and a certain amount of overhead associated with it.

Deploying multiple access points on the same frequency adds range and fault tolerance but won't increase your overall bandwidth. We found that deploying multiple access points can increase the fault tolerance of a wireless segment. When one access point in a segment fails, the wireless clients seamlessly roam to the other access points without interrupting service.

Using three clients on three different frequencies dramatically improves performance. The use of multiple channels is similar to using a switch instead of a repeater on a wired network. Each wireless channel provides about 5 Mbps of throughput in the wireless environment. Cisco, Enterasys and Lucent solutions wowed us with 14 Mbps of aggregate throughput to three wireless clients, each on its own frequency. Unfortunately, most of the units did not let us force association to a particular access point. Thus, to achieve these rates, you must build multiple overlapping cells with different frequencies. This can be tedious if the vendor does not let you specify which access point to associate to. It boils down to manually entering the network ID on the client. Which access point you associate to is based entirely on signal strength for most products; unfortunately, access-point load should play into that equation. 3Com's setup is an exception: It takes both signal strength and load into consideration when associating to an access point.

In the 802.11b standard, under U.S. FCC rules there are 11 distinct channels. These channels represent the center frequency of the wireless transmission wave. In practicality, you can have only three operational frequencies in a given area; thus, 14-Mbps aggregate throughput is close to the best you're going to get using today's technology. This reveals the biggest weakness in wireless LAN--it's not Ethernet, and there is significant overhead in the 802.11b protocol and associated CSMA/CA architecture.

Reviews
Cisco Aironet Beats Rivals--With Ease
While Cisco's 340 Series rides its friendly features to the top, Lucent Technologies' Orinoco solution nabs our award as the best value in 802.11b networking.
By Joel Conover

Cisco Systems Cisco Aironet 340 Series
The Cisco Aironet 340 Series earns our Editor's Choice award because of the wireless hardware's top-notch performance, ease of installation and overall ease of use in our lab tests. Likewise, the Cisco Aironet 340 Series Access Point (AIR-AP342E2C) packs a lot of features and functionality into a very small package. The Cisco access point has features that simplify deployment, and it includes all the functionality an enterprise needs to fine-tune a wireless network. The clear and concise management interface is a dream for both novice wireless users and advanced power users. The interface, which can be accessed via a serial port, telnet or a Web interface, is aware of multiple access points in the network and capable of managing a cluster of wireless access-point devices as a managed group. However, Cisco--and the industry in general--has a long, long way to go to make managing an enterprise of wireless devices less of a headache.

The Cisco Aironet 340 Series PC Card (AIR-PCM342) is well-designed; its solid single-piece construction is rugged and durable. The access point-PC Card combo outperformed every vendor's solution by at least 15 percent in raw throughput tests. The 340 Series PC Card has a 5-volt design. Cisco's product sits in the middle of the pack in terms of power consumption. Its power-saving mode delivers excellent throughput, but the unit's 500-milliwatt quiescent power draw drops it to fifth in our power-consumption tests. The 340 Series' strong showing was gained through proprietary (though interoperable) performance extensions. Our ongoing lab tests have shown that Cisco products don't soar nearly as high when non-Cisco PC Cards are used with Cisco access points.

The Aironet family of products seems to be aimed primarily at Wintel PC users; no support for Microsoft Windows CE or Apple Computer Macintosh was available during our tests. In addition, Cisco charges the most for its units, demanding a hefty $249 per PC Card. The Cisco tax strikes once again. Pricing is an interesting game in this market, however. For example, Lucent Technologies sells its access point for $1,000 but also requires the purchase of a wireless PC Card to put in the access point. Likewise, Cisco charges additional fees for antenna diversity and encryption, even though these options are "software upgrades." And all this is calculated without discounts the vendor may offer.

Cisco's PCI-based adapter is simply a PC Card mounted on a PCI-based PCMCIA host adapter. Most vendors take this approach, and even those that don't (such as Compaq Computer Corp., with its WL200 11 Mbps Wireless LAN PCI Card) still identify the PCI card as a "PCMCIA bridge device." These PCMCIA-on-a-stick solutions work just as well as their PC Card brethren. The vendors making these PCI and ISA solutions are trading off design time for cost of deliverables. That is, does the vendor sell enough PCI and ISA cards to justify creating a lower-cost, integrated design? The answer, it appears, is no. None of the vendors participating provided an ISA or PCI adapter that didn't eventually present a PCMCIA bus to the host--proof that wireless LAN is still aimed primarily at mobile applications.

The 340 Series Access Point is a breeze to use. In terms of management features, this little package has it all, offering options for telnet, Web-based management and serial-based configuration. The hardware is easily mountable. Cisco supplies all the hardware for a professional installation at your business. We had no problems getting this unit up and running. Unfortunately, the hardware affords no place on which to attach external antennae; its dual diversity antennae are permanently affixed to the access point. Cisco didn't provide us with its detachable-antenna model. We had no problems roaming our call center using a single wireless access point.

The access point and PC Cards support 40- or 128-bit encryption. These features are configurable by a license key, which must be bought with the features in mind--that is, you pay only for what you need but don't get the flexibility of everything at a single price.

Cisco Aironet 340 Series Access Point (AIR-AP342E2C), $1,299; Cisco Aironet 340 Series PCI Adapter (AIR-PCI342), $349; Cisco Aironet 340 Series PC Card (AIR-PCM342), $249, Cisco Systems, (800) 326-1941, (408) 526-4000; fax (408) 526-4100, www.cisco.com.

Enterasys Networks RoamAbout Solution
Tied for second place with Lucent's Orinoco, Enterasys Networks' RoamAbout 6.0 Access Point is a powerful wireless solution. Like Cisco's solution, the RoamAbout access point is built with the enterprise user in mind. A serial port can be used to configure the access point initially. Once the unit has been configured, remote configuration is supported via telnet or the provided SNMP utility.

The RoamAbout is one of the most feature-rich access points we tested. The hardware has support for power over Ethernet, which is accomplished by using spare pairs in the Category 5 cable. This greatly simplifies installation in locations where power is not readily available. But you need to be careful with this technology, too: It isn't particularly intelligent, and it most certainly cannot be run through a repeater or a switch. Power over Ethernet is a sort of last-mile power and wire solution designed to simplify wireless installations.

Furthermore, the RoamAbout is the only product we tested that lets you use the remote-power feature as a redundant power source, enabling truly mission-critical wireless networks.

The Enterasys access point uses a PC Card adapter to provide wireless-radio functionality. Thus, as the industry progresses, you can upgrade the wireless radio to the latest technology--a feature shared with products from Lucent and Intermec Technologies. The access point allows a high degree of wireless LAN configurability.

Unlike the PC Cards, the Enterasys access point is not an OEM product. The access point is robust and includes serial and host-based management features, as well as telnet access. Still, like most of the solutions we tested, Enterasys' RoamAbout lacks a complete management package tailored to dozens or hundreds of access points and users.

Enterasys resells the wireless Orinoco PC Card to deliver wireless connectivity both to the access point and to the PC. Like the Lucent card, Enterasys' product delivers performance well above average, and its power consumption and range were among the best we tested.

RoamAbout 6.0 Access Point, $999; 40-bit Encrypt card, $199; 128-bit Encrypt card, $249, Enterasys Networks, (603) 332-9400; fax (603) 337-2211, www.enterasys.com/wireless or sales@enterasys.com.

Lucent Technologies Orinoco Wireless Networking System for Enterprise
Lucent's Orinoco Wireless Networking System for Enterprise earns Network Computing's Best Value award by lowering the bar on wireless pricing. At $179 for Orinoco PC Cards, Lucent's solution costs $20 per card less than its closest competitor and represents a phenomenal improvement over the $500 to $800 per-unit pricing of just a year ago. Lucent's Orinoco PC Card has an integrated antenna; however, it also sports a small accessory connector that can accept an external wireless antenna. Lucent's and Enterasys' solutions were second to Cisco's by a very thin margin. The ease of management and raw performance provided by the Aironet 340 Series gave it a slight edge over Lucent's Orinoco.

Orinoco is a 5-volt PC Card. Lucent provides drivers for almost every operating system, including all flavors of Microsoft Windows, Windows CE, DOS, Linux and Apple MacOS. The Lucent solution is the most widely supported adapter of all the units we tested, a boon for sites with multiple operating systems to support. Lucent's Orinoco took second place in our performance tests, with an average of 4.5 Mbps of throughput and a top throughput of 4.9 Mbps. Orinoco's power utilization under standard operating conditions was the lowest of all the 5-volt cards we tested; when we enabled power-saving mode, it performed extremely well, using only 75 milliwatts of power in quiescent mode, the second lowest of all the products we tested.

The Lucent Orinoco access point features a dual-slot PCMCIA design. This design, Lucent claims, gives you a number of options, including migration from previous wireless technology/standards or, alternatively, a way to improve performance or fault tolerance within a single cell. The access point takes the same Orinoco cards that are installed in notebook computers. It can also be a wireless bridge (building to building) with the extra slot.

The Orinoco access-point management software is functional, but not fantastic. Lucent has been using the same wireless-access configuration software for years; it discovers access points on the network and then lets you configure most of the operational parameters on a per-access-point basis.

Basic access-point features as well as specific wireless parameters are configurable from a single interface. However, only one access point can be managed at a time.

The Orinoco access point checks in at under $1,000. However, Lucent hides some of the cost of its solution in packaging. The Orinoco access point does not come with a wireless PC Card. You must purchase the PC Card separately, putting the cost near $1,200.

Orinoco Wireless Networking System for Enterprise, $995 for WavePoint II access points, $179 for Orinoco PCMCIA cards, Lucent Technologies, (800) WAVELAN, (973) 581-4297; fax (973) 581-3223, www.wavelan.com or vonschaumbur@lucent.com.

3Com Corp. 3Com AirConnect 11 Mbps Wireless LAN
3Com's AirConnect 11 Mbps Wireless LAN product is a pleasure to use. The AirConnect PC Card we received came in a starter pack, which includes three of the wireless PC Cards and a wireless access point for just under $1,800. The AirConnect PC Card is actually an OEM unit from Symbol Technologies. The card features a modular detachable-antenna design. We speculate that excessive wear on the antenna/main body could damage the delicate hinge between the wireless PC Card and the antenna. If you're looking for extra range, you can remove the modular antenna and instead attach an external special-purpose antenna.

In our tests, the 3Com wireless PC Card performed admirably, coming in just behind Lucent's and Cisco's products, with a peak throughput of 4.6 Mbps and an average of about 4 Mbps.

The 3Com client is one of the best we tested; it includes support for Mobile IP, which lets you roam among multiple subnets, a handy feature in a typical, routed enterprise infrastructure. 3Com is also the only vendor that let us specifically choose an access point, rather than having the software just pick the strongest access point. This flexibility is a valuable feature if you are trying to manually segregate your traffic to balance network load. Although it's tedious to configure mobile users, once configured, they can roam just as other users can. You can also automate the process by forcing the user to join a particular network area using the 802.11b ESSID (Extended Service Set ID) field. We still wish there were a better way of associating users to access points.

The 3Com access point boasts a large fixed-configuration antenna. Upon closer inspection, we found the access point actually contains a PC Card radio with a special antenna fixed to the PC Card. That card does not appear to be removable.

Configuration and monitoring tools on the 3Com access point are extremely flexible and a snap to use. Like Enterasys' RoamAbout, AirConnect also supports a power-over-Ethernet technology, which lets you place the access point anywhere you can place an Ethernet port. You can manage the 3Com access point from a serial connection, telnet or Web interface. The management interface also lets you manage multiple access-point configurations from a single access point. You can save a configuration or update firmware from one access point to all access points on your network (Cisco's Aironet also supports this feature). We found this feature to be potentially useful but a bit buggy when it came to firmware upgrades. We hope 3Com will work these bugs out in a future code release. Unreliable code is worse than not having the feature at all.

3Com AirConnect 11 Mbps Wireless LAN, starts at $1,795 for the starter pack of one access point and three PC Cards, 3Com Corp., (800) NET-3COM, (408) 326-5000; fax (408) 326-5001, www.3com.com.

Intermec Technologies Intermec 2101 Universal Office Access Point Solution
Intermec provided us with a unique wireless solution that includes its Intermec 2101 Universal Office Access Point and a 3.3-volt Orinoco PC Card. Intermec's hardware relies on external antennae, which have advantages and disadvantages. Having an external antenna on a wireless PC Card offers the opportunity for extended range and performance, but it also requires a small wire to run from the PC Card to the external antenna. In a typical environment, the external wire is both cumbersome and prone to damage. We see the Intermec solution being used primarily in applications in which users are not mobile but require wireless technology to provide connectivity.

The Intermec wireless access point is a two-port PCMCIA-based wireless solution, in some ways similar to Lucent's Orinoco wireless access point. Like the wireless PC Cards in the workstations, however, Intermec uses external antennae for its access-point product. The Intermec wireless access-point product is easier to configure than the Lucent product; the 2101 features a serial port and telnet and Web-based interfaces to configure and manage the device. However, Intermec's access point is almost twice as expensive as the other products in this review. Historically, Intermec has delivered rugged products designed for outdoor use. However, this access point has a simple plastic design, certainly not suited for the industrial applications at which it seems to be aimed.

Intermec's performance was very middle of the road, with average throughput of around 4 Mbps. On the positive side, the wireless client had the lowest quiescent power utilization--only 53 milliwatts.

Intermec 2101 Universal Office Access Point, $2,090; Intermec 2102 Access Point, $950; Intermec 2126 PC Card, $229, Intermec Technologies, (800) 347-2636, (425) 348-2600; fax (425) 355-955, www.intermec.com or info@intermec.com.

Compaq Computer Corp. WL100, WL200, WL300, WL400 Wireless LAN Solution
Compaq presented us with a complete wireless networking solution that included access points, PC Cards, PCI cards for desktop systems and a unique software wireless access point. Compaq's package appeared to have all the right pieces, but the performance and range just weren't there.

Compaq's wireless PC Card is 3.3 volts and is manufactured by Intersil Corp. In our tests, the Compaq card had the lowest overall performance. In our call-center range tests, the wireless signal dropped off almost completely at the center of our coverage area. Whether this is the fault of drivers, antennae, access points or the PC Card itself, we were unsure. Compaq lauded the card as having superior 3.3-volt technology, citing the way it integrates with the end-to-end solution, including Compaq's handheld personal organizer. In our tests, the 3.3-volt card did use far less power than some devices, but its power utilization was mediocre--759 milliwatts during quiescent operation with power saving enabled.

Compaq's access point is a NoWires Needed OEM product. The access point is manageable only via the NoWires Needed management software, which--as we mention below--isn't particularly user friendly. The access point is a fixed-configuration device, with no removable (PCMCIA) radios.

One impressive product in the Compaq solution is the software access point. Rather than spending upward of $1,000 per access point, you can turn any spare PC into a fully functional access point with this software. Using Compaq's WL200 11 Mbps Wireless LAN PCI Card, you can build a wireless access point for less than $325 (compared with $899 for the hardware access point). The wireless access-point software can significantly lower the total cost of ownership of a wireless solution and can be an ideal SOHO solution, given that every PCI NIC is bundled with a standard-license edition of Deerfield.com's WinGate, which is a popular NAT (Network Address Translation) and proxy software package. Our tests showed the software access point is just as functional as a hardware-based access point in terms of performance and interoperability.

WL400 11 Mbps Wireless LAN Hardware Access Point, $899; WL100 11 Mbps Wireless LAN PC Card, $199; WL200 11 Mbps Wireless LAN PCI Card, $199; WL300 11 Mbps Wireless LAN Software Access Point, $125, Compaq Computer Corp., (800) 345-1518; fax (281) 518-1442, www.compaq.com.

The NoWires Needed 11 Mbps Wireless LAN
The NoWires Needed 11 Mbps Wireless LAN solution we tested was an early beta. During the course of our tests, the company was purchased by Intersil (the company that makes the Prism chipset). NoWires Needed is an OEM provider of wireless equipment for several of the LAN wireless vendors, including BreezeCom and Compaq. However, the equipment we tested was a different generation and model than the OEM equipment the company provides to other vendors.

The 5-volt wireless PC Card provided by NoWires Needed has a fixed-antenna construction. In our lab tests, the NoWires Needed card turned in the best encrypted performance--it was the only card to come in above 5 Mbps with encryption enabled. Furthermore, this card has great power-utilization statistics. The NoWires Needed product doesn't have a power-saving "mode"--it always operates in power saving. Power consumption in quiescent mode was about 150 milliwatts--lower than many of the competitors' results in power-saving mode.

The NoWires Needed driver suite is a bit sparse in terms of diagnostic tools. However, NoWires Needed took the extra effort to provide highly visible encryption warnings and information, a detail the other vendors overlooked.

The NoWires Needed access point is small but effective. Integral to the NoWires Needed solution are the options for 40-bit or 128-bit encryption, or NoWires Needed's own 128-bit AirLock security. A public/private key exchange system that eliminates the need for distributing shared keys in an encrypted environment, AirLock is an unusual and innovative feature that takes wireless security to a new level. Of course, AirLock is proprietary, and it prevents people only from "sniffing" your wireless data from the air. AirLock's key negotiation eliminates one aspect of security by not requiring the user to enter a public key. We think the trade-off of keyless security is well worth the lack of public keys. Fortunately, NoWires Needed hasn't ignored the need for standards-based encryption. If AirLock isn't available, the client will drop back to standard 40-bit or 128-bit encryption as the environment provides.

NoWires Needed provides management software to configure and monitor access points. However, we weren't impressed by the NoWires Needed management tool, which is also used by several NoWires Needed OEMs. The management software keeps its own state, which didn't always match the state of the access point, making management cumbersome. The software often didn't reflect the state of the remote access point, and sometimes changes we made weren't represented on the remote device.

Priced at $219 for a client PC Card and $999 for the Enterprise Access Point, the NoWires Needed solution is a solid performer and a good bargain.

NoWires Needed 11 Mbps Wireless LAN, $219 for PC Card, $999 for Enterprise Access Point, $499 for Small Business Access Point, NoWires Needed BV, +31-30-229-60-60, (650) 330-1466, www.nowiresneeded.com or info@nwn.com.

Farallon Communications SkyLine 11 Mb Wireless PC Card
Farallon Communications is yet another vendor offering a wireless 802.11b high-rate PC Card, but the company does not make an access-point product. We recently tested Farallon's 802.11b wireless product on the Macintosh in our Real-World Labs® at the University of Wisconsin-Madison (see "Farallon's Faster SkyLine Does Mac and Windows, Too.") Here we find it again; however, this time the tests focus on the Wintel platform. The Farallon SkyLine 11 Mb Wireless PC Card is an Intersil OEM product, but Farallon has done additional development to provide support for the Mac. Note that this is not the recently acquired NoWires Needed product we cover above, but another (older) Intersil reference design.

In the lab, the Farallon card performed around the top end of average, with a maximum throughput of 4.5 Mbps and an average of around 4.2 Mbps. WEP-encrypted performance was respectable, too, with top throughput exceeding 4 Mbps and average throughput of around 3.8 Mbps.

The Farallon card has an integrated antenna and driver support for MacOS and Windows 95/98 and NT 4. At $199, Farallon's SkyLine is competitively priced.

SkyLine 11 Mb Wireless PC Card, $199, Farallon Communications, (800) 613-4954, (510) 346-8000; fax (510) 346-8119, www.farallon.com or info@farallon.com.

Zoom Telephonics ZoomAir Wireless Networking
Zoom Telephonics also provided us with a wireless PC Card. The ZoomAir Wireless Networking card is actually an Intersil OEM product. Zoom's product matches Lucent's in price, coming in at a low $179 per card. The ZoomAir is a 5-volt card with a permanently attached antenna. As we mention in "Top 10 Things To Know About Wireless" (see www.network computing.com/1113/1113f2side2.html), the wireless industry is dominated by a small number of hardware manufacturers. The difference in OEM products comes in antenna design as well as driver implementation.

In the lab, ZoomAir's unencrypted performance was on the low end, averaging about 3 Mbps. With encryption enabled, however, the Zoom card zoomed right along, delivering the fourth-best performance of all the products we tested--a solid 4 Mbps.

ZoomAir's installation procedure is meant to be idiot-proof, but it was designed poorly. To install ZoomAir's drivers, you must use the company's setup utility, which installs IP, IPX and NetBEUI protocol support on your operating system whether you want it or not. Of course, you can remove these protocols, but there is no reason the install should unnecessarily add them to your operating system.

Zoom also offers a software access point, but because the company didn't have a PCI card ready in time for our review and provided only two PC Cards, we were unable to test that product in our lab.

ZoomAir Wireless Networking, $179, Zoom Telephonics, (800) 631-3116, (617) 423-1072; fax (617) 423-3923, www.Zoom.com or sales@zoom.com.

BreezeCom DS.11 Wireless Solution
BreezeCom provided us with its AP-DS.11 Access Point 2.4.0 and SA-DS.11 Station Adapter 2.4.0 solution. Unlike the other vendors, BreezeCom did not provide us with any PC Card adapters. Instead, its station adapter looks like a standard access point but provides Ethernet-to-wireless connectivity to a wireless network, which is just the opposite role that an access point plays.

And unlike some of the other products we tested, BreezeCom's DS.11 solution offered no encryption and no power-saving mode. Then again, because the units must be plugged into the wall, power saving really isn't an issue.

Managing the DS.11 hardware is done from BreezeCom's GUI-driven SNMP manager. Like most of the configuration and monitoring tools we tested, this one was a little clunky. We had a hard time getting it going, but once we figured out the nuances, we were able to configure the hardware appropriately. The performance of the DS.11 was average at around 4 Mbps.

AP-DS.11 Access Point 2.4.0, $1,195; SA-DS.11 Station Adapter 2.4.0, $795, BreezeCom, (760) 517-3100; fax (760) 517-3200, www.breezecom.com or sales@breezecom.com.

Zcomax Technologies XI-300 11 Mbps Wireless PC Card
Zcomax Technologies provided us with its XI-300 11 Mbps Wireless PC Card. The Zcomax hardware features a detachable antenna, with a construction similar to that of the 3Com card. Zcomax informed us, however, that it is a top-level hardware provider; that is, it makes its own PC Cards and is an OEM provider to other manufacturers. Power consumption for the XI-300 was much higher than the competition's--1,225 milliwatts in quiescent mode. Performance was average, around 4 Mbps in our client-server tests.

The Zcomax card does not support encryption, so we were unable to test that feature. We spoke with Zcomax about XI-300's power utilization and performance and found out the company is releasing a new driver, but that driver was not available for our tests. The old driver did not have power-saving mode implemented, even though it was an option in the controls; that explains the poor power utilization.

XI-300 11 Mbps Wireless PC Card, $199, Zcomax Technologies, (562) 926-4588; fax (562) 926-7885, www.zcomax.com or sales@zcomax.com.

Send your comments on this article to Joel Conover at jconover@nwc.com.

Executive Summary 802.11b Wireless Wireless LANs have undergone a major face-lift in the past year. With the advent of the 802.11b high-speed wireless standard, vendors are delivering high-performance, interoperable solutions that won't gouge your IT/IS budget. The 11-Mbps wireless systems we tested varied in actual throughput from 4 Mbps to 6 Mbps, a significant improvement over the 1 Mbps to 1.5 Mbps we saw just a year ago with the 2-Mbps products of the 802.11 standard. The 802.11b standard has given vendors a major reason to innovate. The cost of a wireless radio is down--way down. For about $180, you can pick up a wireless PC Card capable of connecting you to an 802.11b network; that's 200 percent to 400 percent less than prices of a year ago. And this time, the vendors' products work together. You can thank WECA (Wireless Ethernet Compatibility Alliance), the IEEE and a diligent group of vendors for ensuring that these wireless products will interoperate. So are you ready for wireless? Cisco Systems is. Its $900 million acquisition of Aironet is the checkered flag for the networking industry. Cisco's Aironet 340 Series wireless solution takes the Editor's Choice award in our review, with unbeatable performance and solid device-management features. Lucent Technologies kicks in just a hair behind on the performance charts, and its Orinoco Wireless Networking System for Enterprise earns our Best Value award. Wireless is no longer just a solution for places where wires can't reach; it is a solution for the mobile business professional. Top 10 Things To Know About Wireless Curious about interoperability, encryption, management and standards? Here's the lowdown on wireless technology today. By Joel Conover 10. Cost Thanks to integrated chipsets from Intersil Corp. (formerly Harris Semiconductor), Lucent Technologies and other component manufacturers, the cost of developing and delivering a wireless solution has dropped significantly. The result is a PC Card solution that is on par with that of wired Ethernet. The products we tested for this article list for $179 to $249 per card? A price that can be easily justified for home office or mobile users. Wireless has become cost effective; for its PowerBook line of notebooks, Apple Computer even has a wireless module that costs just $99, a price we expect most vendors to hit within 12 months. 9. Performance Wireless performance has nearly quadrupled over solutions based on proprietary or even 2-Mbps products using 802.11. Single-card performance can reach 6 Mbps, which is more than sufficient for the average business user. Much of this is thanks to the 802.11b high-rate standards body, which was driven primarily by Lucent and Harris. The 802.11b standard uses a technology called CCK (complimentary code keying) to encode the wireless data in a format that fits within the 802.11 DSSS (direct-sequence spread-spectrum) FCC rules. CCK is what allows these wireless devices to operate at 11 Mbps. Of course, CCK is not without its trade-offs; 11-Mbps products have significantly shorter range than their 2-Mbps counterparts. Fortunately, most vendors have implemented 802.11b products that drop back to 5.5 Mbps, 2 Mbps and 1 Mbps as range increases. As you inspect our performance charts (on page TK and pages TK-TK), it is easy to identify where the cards under test dropped down to lower rates to support increased range. 8. Interoperability The 802.11b high-rate wireless standard is the best thing ever to happen to the industry. In our labs, we found that every one of the products we tested was capable of interoperating with products from competing vendors. The fact that we needed no special engineering support to make any of these products work together tells us that this technology has finally jelled. Rather than 11 vendors delivering 11 wireless products, there is one industry capable of delivering a wireless Ethernet solution. The efforts of the IEEE and the Wireless Ethernet Compatibility Alliance (WECA) and work being done at the University of New Hampshire are making wireless interoperability a nonissue. The work of these groups guarantees 802.11b will be the future of high-speed wireless. Without these groups and participation of the wireless networking vendors en masse, 802.11b would just be another shot-in-the-dark technology. WECA's WiFi (Wireless Fidelity) branding scheme is your guarantee that the wireless products you buy will be interoperable. 7. DS Reigns Over FH There is an almost religious war raging between the DS (direct sequence) and FH (frequency hopping) camps. However, because of the technology used in 802.11b, only DS solutions can operate at 11 Mbps. Fortunately, DSSS offers superior range and performance, and today's technology makes it affordable. DS technology uses a chipping code to spread a signal across a larger chunk of spectrum. A typical 2-Mbps DS system uses 11 chips to spread its signal, resulting in about 22 MHz of spectrum utilized. Note that there's 83.5 MHz of bandwidth, so you can get three clean DS channels out of the 2.4-MHz ISM (industrial, scientific and medical) band. In contrast, FH transmits across a set of very narrow bands. If one or more of these bands are polluted with noise, the radio simply skips that channel and moves on. Because the radios spend only a small amount of time in each band and there are plenty of bands (79 bands of 1 MHz in the sequence), FH theoretically can scale better and offers greater immunity from interference in most cases. DS gains a slight performance advantage over FH, because both the channel bandwidth is greater and it doesn't have any latency while switching channels. Although this latency is very small, it does add up to a performance hit. To its detriment, DS does not scale as well when it comes to the number of nodes in a given area, and there will be more susceptibility to signal interference as you scale a DS network compared with when you scale a FH network. DS radios once also were very expensive to build, compared with the relatively cheap FH radios. FH radios rely on the host driver software to take care of some MAC (Media Access Control) layer issues. Specifically, a packet cannot be spread across a hopping boundary; thus, the MAC layer must make sure the packet will fit in the remaining time slice of the current hop. If the packet cannot fit in the current hop, then it must wait to transmit until the beginning of the next hop. In contrast, DS radios must deal only with a high-speed chipping code. The speed necessary to accomplish this chipping was once cost prohibitive; however, today's low-cost ASICs and DSPs (Digital Signal Processors) have made it easy and cost effective to build a DS wireless solution. The 802.11b high-rate standard uses multiple chipping codes and other special processes to achieve its high-speed rate. Because of these multiple codes, the signal-to-noise tolerance is not as high. The result is decreased range at 11 Mbps. The religious war may be drawing to an end, however, because 802.11b high-rate wireless can be implemented using only a DS radio. So even though FH technology has some merits compared with DS, DS will be the long-term winner. 6. Encryption Thanks to an accommodating standard and well-written drivers, it is easier than ever to pick up on a wireless Ethernet conversation and listen in as you see fit. In the lab, we were able to sniff packets out of the air with ease.. Not only that, but while wandering outside near the windows of our call center, we could tap into the corporate network. Encryption shouldn't be an option on your shopping checklist. WEP (Wired Equivalent Privacy) is an option that sits on top of the 802.11b standard, but almost every vendor is supporting it in some fashion. Although we didn't do a complete interoperability matrix, our lab tests show that WEP appears to be just as interoperable as the 802.11b standard itself. But beware: WEP can be a management nightmare. Because it uses a shared key system, you are responsible for distributing passphrases, hex keys or ASCII strings that represent your wireless-encryption key. If that key is leaked, your data is compromised. The difficulty of changing keys varies from vendor implementation to vendor implementation, and though not complicated, the keys can be hard to disseminate securely. One vendor, NoWires Needed, has developed a unique public/private 128-bit key exchange algorithm called AirLock. With AirLock, every session is encrypted, and AirLock's operation is transparent to the user. The AirLock system uses a public key exchange to negotiate an encrypted session; private keys are established once the initial encryption has taken place. The result is a highly secure wireless network with absolutely no need to disseminate keys to end users. If only WEP could work that well. 5. Management Wireless management and configuration tools are, plainly put, pathetic. In more polite terms, the state of wireless network management leaves much to be desired. Most vendors offer only paltry device-configuration tools, with no concept of enterprise management, monitoring or capacity planning. Of the products we tested, the best of the bunch offered Web-based device management. This is simply unacceptable. For one thing, it is nearly impossible to push an enterprise change out to multiple access points. Trying to accomplish this task via a Web browser is tedious, even if the Web interface supports the option to configure multiple access points?and few do. Many of the products lack even a Web or serial-based interface. Instead, you must individually configure the devices via a (semi-)proprietary SNMP tool. These tools don't offer much in the way of capacity management or network monitoring. To successfully manage a wireless network, your NMS (network management system) solution must be aware of mobile devices and users. Only one vendor? Symbol Technologies?has anything that approaches the needs of a true enterprise management solution, and that solution is proprietary to its access points. Vendors need to deliver effective device management before this technology can truly be deployed in the mainstream. 4. The Reseller Market The wireless market may look big, but the number of players is really pretty small. There's Lucent, which sells to Apple, Enterasys Networks and Intermec Technologies, among others. Likewise, Symbol provides equipment to Intel Corp. and 3Com Corp. There are only a few other top-level providers, such as Zcomax Technologies. Intersil supplies reference cards and chips to a number of vendors, including Compaq Computer Corp., Farallon Communications and Zoom Telephonics, though Intersil doesn't deliver directly to the retail channel. And NoWires Needed delivers access points to Compaq and BreezeCom, as well as delivering its own access points and cards directly to the market. Cisco's Aironet series belongs solely to Cisco, though Dell Computer Corp. and Aironet (prior to being owned by Cisco) had a reseller (OEM) agreement. And in this market of OEMs, the number of radio manufacturers is even smaller. The radio, of course, is that tiny bit of hardware inside your PC Card that makes this all work. Intersil and Lucent comprise nearly the entire radio market. 3. Wireless Is Not Ethernet One of the most interesting aspects of wireless Ethernet is that it's really not Ethernet at all. Although 802.11b shares some common aspects of an Ethernet network, in reality, wireless is a CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) network. The 802.11b standard has a raw bit rate of 11 Mbps. The wireless MAC layer is only 70 percent efficient to begin with. This is primarily because of the CSMA/CA and Random Backoff protocol, which is a necessity in a wireless environment. In a wired network, the adapter can listen to the wire and hear collisions as they happen. But in a wireless environment, the transmitting signal is so locally overpowering that collision detection isn't an option. Thus, CSMA/CA must be used to guarantee that collisions are minimized, and data is delivered reliably. CSMA/CA utilizes the RTS/CTS (Request To Send/Clear To Send) protocol to notify other workstations that a transmission is about to take place. This four-way handshaking minimizes the number of collisions and makes sure that hidden nodes are aware of transmissions across the entire wireless segment; however, this method introduces significant overhead on the network. The wireless MAC is also significantly more complex than a typical Ethernet MAC. Wireless includes four MAC addresses instead of the two found in an Ethernet header. Finally, to maintain backward compatibility with 802.11 devices, the 802.11b wireless device transmits the preamble and a portion of the packet header at 1 Mbps. This accounts for a significant amount of additional overhead, as the preamble here is significantly longer than an Ethernet preamble. The overall result is a network that can be at most 70 percent efficient (allowing a maximum data rate of about 7.7 Mbps). Losses can be eliminated or reduced by improving the strength of the primary signal, reducing the time it takes to discern ghost signals from the true signal and reducing the amount of time it takes to sample diverse antennas. All this adds up to a wireless standard that really isn't Ethernet at all. Vendors also can "push" throughput at the cost of interoperability. In the case of point-to-point devices, eliminating the 1-Mbps 802.11 legacy transmit speed can significantly improve performance. Likewise, if a network is known to be point to point, the Random Backoff algorithm, interframe gap and preamble can all be minimized to maximize throughput. It is important to note that in a point-to-point application, 802.11b compliance is more of a liability than a benefit?the price you pay in throughput is not worth the gains of a standards-based wireless service. 2. Other Wireless Standards There are at least a six working groups and wireless organizations dedicated to wireless technologies other than 802.11b. For example, HomeRF is building a home networking protocol and standard for all sorts of home-based cordless devices, and the group is petitioning the FCC for rules modifications that will permit high-speed FH using 5-MHz channels. Other groups include Bluetooth, HiperLAN2 and 802.11a. Bluetooth and 802.11b will coexist, even though they share the same spectrum, and there may be the potential for some interference (resulting in lower throughput). Bluetooth is designed as a peripheral interconnect wireless point-to-point protocol. HiperLAN2 is a next-generation technology that will deliver 54-Mbps wireless access in the 5-GHz spectrum. Like WECA, the HiperLAN2 group will be responsible for guaranteeing interoperability of these devices. The HiperLAN2 Global Forum is the equivalent of WECA for the HiperLAN2 standard. HiperLAN2 is being driven by ETSI BRAN (Broadband Access Radio Network). Interestingly, IEEE 802.11a shares the same physical layer as HiperLAN2 technology. Only the MAC is different. 802.11a is all but complete on paper, thanks to the work of these two groups. The HiperLAN2 standard will take longer to finalize because the working group must design an entirely new MAC protocol. Vendors are fence-sitting, with one foot in each camp, waiting to see which product will receive universal acceptance. One important thing to consider with 802.11b is that it is an end-of-the-line technology. Upgrading to 5-GHz technology will be much like converting from an Ethernet network to FDDI. Your existing access points may have upgradable radios (removable PC Cards), but chances are that the network interface to the wired LAN won't be able to keep up with the 54-Mbps data rate. That means new access points. Thus, don't buy 802.11b with plans to upgrade to faster 5-GHz networking in the immediate future. That will be a forklift upgrade. But you shouldn't wait for 802.11a either?affordable 802.11a products are at least three years away. 1. New Wireless Products The wireless industry is responding to the growing market by providing new tools and appliances to take advantage of wireless deployments. In addition to testing the 11 solutions sent for this article, we also had the opportunity to test two wireless accessories designed to work in conjunction with enterprise wireless infrastructures: SpectraLink Corp.'s NetLink Wireless Telephone System and WRQ's NetMotion 1.0 software. The SpectraLink solution is an 802.11 DS wireless VoIP (voice-over-IP) telephone system. Working in conjunction with your existing wireless infrastructure, the NetLink DS solution provides 802.11 DS telephones that can be used anywhere you have wireless coverage. We tested the NetLink solution in conjunction with the 802.11b products in our review. The NetLink hardware is a VoIP gateway into your wireless network. The solution comprises wireless phones and an Ethernet VoIP gateway. We found that the solution was stable and functional, but it used a significant amount of bandwidth on the wireless network. On average, a single call used almost 1,000 Kbps when a call was in session. That doesn't make for a highly scalable solution. While the NetLink solution is a snazzy technology, a maximum of five clients per network is not realistic for an enterprise setting. There is no reason this technology couldn't use 64-Kbps encoding to accomplish the same job. WRQ's NetMotion is designed to deal with the transient nature of wireless connections. Many connection-oriented applications don't deal well with the temporary loss of signal that can occur when a wireless client moves out of range. WRQ's NetMotion attempts to solve that problem by acting as a proxy agent for your wireless communications. TCP sessions are held open by the proxy agent (a dedicated Microsoft Windows NT workstation). When a wireless user roams outside the coverage area, the proxy agent maintains the application session until the user returns to the wireless coverage area. In our brief tests of NetMotion 1.0, the software seems to live up to its promises, at least for the telnet sessions we attempted through the NetMotion proxy. By the Numbers How We Tested 802.11b Wireless Devices Our lab and real-world tests uncover which of these solutions makes the grade in throughput, power utilization, range and encryption. By Joel Conover We used the facilities at the Schneider National labs in Green Bay, Wis., to provide a wireless test bed. In our tests, we used Chariot 3.1 from Ganymede Software to perform all our benchmarks (see a diagram of our test setup below). Our primary test workstations were provided by Compaq Computer Corp. Compaq supplied us with an Armada E500 enterprise desktop-replacement notebook, which ran at 500/700 MHz. We conducted all our Microsoft Windows NT and Windows 2000 testing, as well as additional Windows 98 tests, on this system. Compaq also provided us with a consumer-grade Presario 1600XL-145 500-MHz notebook, which we used as a dedicated Windows 98 client for our tests. An IBM ThinkPad 600E filled out the test bed. We thank Compaq's press evaluation team for lending us the necessary laptops. We used TouchStone Software Corp.'s CardWare 6.0 and SystemSoft's CardWizard 5.1 to provide PCMCIA card services under Windows NT. Four of our tests were designed to measure raw file-transfer throughput, in the following configurations: single-client to single-server throughput in non-power-saving mode; single-client/server throughput in power-saving mode; single-client/server throughput with WEP (Wired Equivalent Privacy) encryption enabled; and multiple-client, multiple access-point aggregate throughput. For each of these tests, we executed Ganymede's filesndl script using a file size of 10,000 bytes. During each round of testing, we measured receive throughput, transmit throughput and bidirectional throughput using the filesndl script, which imitates file transfers that might be seen on a typical enterprise network. We also used Ganymede's SAP purchase-order simulation to measure small-packet throughput and round-trip response time. In all our tests, we used a PC Card breakout device and a Fluke Corp. multimeter to measure the current draw of each vendor's wireless PC Card. We thank Intel Corp. for providing us with the necessary hardware to perform these measurements. Power consumption varied significantly from one vendor's product to the next; however, there was almost a one-to-one correlation between power usage and throughput; thus, you pay for performance in battery life. In addition to these "white room" lab tests, we took all the products into Schneider National's call-center facility and tested them in an unbeatable real-world environment. We placed each vendor's access point in a conference room overlooking the call center and then, using the Chariot program, ran four throughput tests from strategic places around the call center. This clearly demonstrated which products have the best range and superior antenna design. The call center is approximately 110 feet by 100 feet, in a roughly hexagonal shape. The conference room overlooks the eastern portion of the call center. The call center is filled with equipment that generates a typical amount of electromagnetic interference in a building. We performed a complete ping survey of the site using each vendor's solution, searching for dead spots and unusual latencies. We chose four test locations with approximate distances of 25, 55, 85 and 110 horizontal feet from the access point and ran benchmarks from a cubicle at each distance. Other than the glass wall between us and the access point, the only walls in the room were the cubicle dividers placed in rows along the entire call-center floor and the six walls that make up the call center. In addition to these tests, we performed a significant number of other tests to determine the scalability of the wireless products, as well as the throughput and performance of OSes other than Windows 98. A complete test log is available online in Microsoft Excel format. Throughput: One to One In our one-to-one throughput tests, we used a single Windows NT workstation client to talk to the wireless card installed in our Compaq Armada E500 workstation running Windows 98. We ran this test at approximately 10 feet. All NIC and access-point options were left configured as defaults (see "Single-Client Performance," page 86). In all three of our single-client, single-server tests, Cisco's Aironet 340 Series NIC and access point posted a clear 15 percent performance margin over the nearest competitor. Cisco attributes this showing to two factors: IEEE 802.11b short-headers and proprietary performance options in the 340 Series hardware. We had both features turned on, as these options come enabled by default. The 802.11b short-headers feature is an option that helps improve radio performance. Even with these features enabled, Cisco's product interoperated smoothly. Lucent Technologies' and Enterasys Networks' solutions shared a healthy second place with their offerings, with most other vendors' products lagging just a hair behind. Average throughput among all the devices was roughly 4 Mbps in our one-to-one client tests. In our second round of tests, we used the vendor-supplied method of encryption (either 40-bit or 128-bit) to encrypt the data being sent over the test network. In this round, the NoWires Needed solution took top honors for maximum throughput, achieving 5.5 Mbps in our receive test. Cisco's product took a solid second place, reaching 5 Mbps. Most of the remaining products averaged 3.6 Mbps. In this segment of testing, we looked for increased CPU utilization and/or power draw. Power draw remained consistent across our tests, but CPU utilization on most cards varied. Notably, cards from Compaq, Farallon Communications and Intermec Technologies showed little or no CPU utilization changes with encryption enabled. Compaq and Farallon use a 3.3-volt Intersil card, which reportedly has an onboard CPU to assist in WEP encryption. Intermec uses a 3.3-volt Lucent Orinoco card. (Enterasys and Lucent use a different, 5-volt card.) Throughput: One to One, Power-Saving Mode Our third round repeated the original test configuration. Here the goal was to determine how power management affected throughput and power consumption. We found significant differences in power utilization and throughput when in power-saving mode. In our throughput tests, NoWires Needed's solution inched ahead of the competition, with Cisco's and 3Com's products close on its heels. The devices from NoWires Needed topped the charts at 4 Mbps to 4.5 Mbps in our throughput tests. Most other units averaged around 3.2 Mbps. We learned some interesting things about wireless power management during this round of testing. Contrary to what you might think, power management is not directly related to transmit power, distance from the access point or other environmental factors. Wireless radios, such as those in the PC Cards, use a fixed amount of power to transmit and receive data. Typically, 802.11b devices operate in what is known as CAM (constant access mode). However, the 802.11b standard also supports a polled access mode. When the card is put in this mode, the driver can cut power to a bare minimum for intervals of 100 milliseconds or more. Once each poll period, the card communicates with the access point and receives data that has been buffered for a small amount of time. The result is that the wireless card does only 10 percent of the work it does under CAM. This works well in environments where throughput is low and/or the network is not very busy. However, as utilization increases, this mode has less value to the end user. The more data that must be transmitted each poll period, the less rest the adapter will have. This was evident in our throughput tests. When our tests were running full blast, most units showed little, if any, difference between CAM operation and polled operation. And with power management enabled, throughput was often significantly reduced. In quiescent power-consumption mode--that is, when the card is neither transmitting nor receiving--the solutions from Compaq, Farallon, Zcomax Technologies and Zoom Telephonics showed very little difference in power utilization from their standard modes. NoWires Needed's solution also showed no significant deviation. However, unlike other products, that from NoWires Needed always operated in power-saving mode, and therefore it was one of the few units whose performance didn't drop sharply when in that mode. The other vendors' cards all saved a significant amount of power in quiescent mode. Wireless Range and Performance Our final tests took us to the Schneider National call center, where we roamed to various checkpoints and tested throughput and range. Although each of the cards reported a signal across the entire 11,000-square-foot facility from a single access point, throughput and reliability varied greatly. Units from Cisco, Enterasys, Lucent and 3Com demonstrated significantly better performance and reliability than the others. The range of the 3Com solution seemed to be strongest, possibly because of its larger antenna. Other products we tested delivered intermittent performance results and lower throughput overall. We found that throughput dropped off significantly toward the middle of the call center, but performance picked up near the far wall. This is most likely because of signal reflection and emphasizes the need to place your access points carefully as you plan your network.