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-------------------------------------------------------------- This story was printed from ZDNet Australia. --------------------------------------------------------------
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Wireless lans get to work September 25, 2001 URL: http://www.zdnet.com.au/reviews/coolgear/wireless/soa/Wireless-lans-get-to-work/0,139023505,120217706,00.htm
Wireless LANs have finally matured into a viable and affordable means of extending your wired network. Mercedes-Benz USA had a problem that many businesses face. The company maintains volumes of information--vehicle inventory, repair records, and automobile troubleshooting, among other things--in its corporate databases and intranets. Mercedes-Benz employees often need to access these files when they're not plugged into the company's LAN (on dealership floors, in garages, or under the hood of a car). Enter 802.11b wireless network access. Once regarded as a high-tech plaything for the executive conference room, wireless LAN technology is now a viable option for mainstream businesses, thanks to lower cost, improved inter-vendor compatibility, and the emergence of wireless Internet access in public places.
Basically, a wireless LAN replaces the last three metres of Ethernet cable between your laptop and the wall. Mercedes-Benz has installed wireless LANs in 10 percent of its dealerships so far, and it's hoping to set up frame relay networks in all 430 dealerships nationwide. Larry Roll, supervisor of network telecommunications at Mercedes-Benz USA, says, "Now the service techs have a way to hook right into the network." Once the wireless LAN access point was set up, which was simple to do and took only about one hour, employees were able to connect to the intranet and Internet from almost anywhere within the Mercedes-Benz facilities. The sales staff, for example, can use the wireless LAN directly from the showroom floor to locate a particular car model or colour for a customer. Mechanics use the wireless LAN to diagnose problems, order parts online, and retrieve a car's maintenance history.
text cont... There are two main components in a wireless LAN: access points (APs) and PC Cards that slide into the expansion slots in notebooks. Both components are receiver/transmitters. The AP and PC Cards communicate with one another via the 2.4GHz radio band, which allows indoor mobility reaching 25 to as much as 100 metres from a given access point.
Early wireless LANs were very expensive to implement and manage, and many were proprietary solutions. Five years ago, a 2Mbps AP could cost as much as AU$5000, and wireless PC Cards as much as AU$1500 each. The arrival of the 11Mbps 802.11b standard in late 1999 changed everything. Adoption of the standard and the availability of off-the-shelf chip sets quickly brought costs down. In fact, the most expensive access point in our roundup costs AU$3505, and some very capable units now are available for as little as AU$1000. Client PC Cards cost AU$295 to AU$536, which is a lot less than the highest PC Card price in 1998.
With a wireless LAN, users can access network services from conference rooms, offices, and even public spaces within the building. Wireless LANs are particularly well-suited to places where traditional Ethernet networks are too expensive or too cumbersome to install. And this technology can be used to cover larger areas such as warehouses and college lecture halls where Ethernet cable is impractical. Even better, you can take your entire network with you if you move to a larger space. Several companies--including D-Link Systems and Linksys--offer low-cost 802.11b wireless systems designed specifically for the home and small-office markets. These systems follow on the heels of the immensely popular Apple AirPort wireless network system, introduced in late 1999. Seal of Approval
The heart of any 802.11b device is the radio chip set. Currently, there are only two 802.11b chip set manufacturers: Intersil and Lucent Technologies. When we began our testing, the WECA Web site showed that there were 67 Wi-Fi-certified products from 28 different vendors. During our tests, we found that many of those products use the same technology in different packages. We included them because each vendor claims that its product is unique, thanks to the drivers, installation software, and utilities packaged with the products. 3Com, for example, has additional security and client configuration features not found in the other Symbol Technologies-based products. With so few manufacturers and such stringent compatibility testing, we expected 100 percent interoperability. This expectation was achieved with some minor tweaking. A Secure Environment
All Wi-Fi products support wired equivalent privacy (WEP), a security specification that uses 40-bit encryption to scramble wireless data on the fly. While 128-bit encryption is not currently part of the specification, it is under study and is already supported by several vendors. WEP is implemented on both the access point and the client side of the connection, and WEP requires the use of shared keys on all access points and clients in the system. To enable WEP, users must enter the security keys manually on each client when installing wireless network cards. This is very time-consuming and can be a major obstacle to wide-scale deployment. The Cisco Aironet 350 is the first solution to address this shortcoming.
Editors' Choice Awarding an Editors' Choice award in this story's Enterprise category was not an easy decision. We really liked both the Cisco Aironet 350 Series and the Lucent Orinoco AP-1000. After weighing all the evidence, we reached the conclusion that the Orinoco AP-1000 offered the best features and performance mix, thus earning our Editors' Choice (with Cisco nabbing a strong honourable mention). The Orinoco AP-1000's list of great features, including excellent site-survey and link-testing tools, superior AP and client-configuration managers, and strong performance, are the chief reasons we put it on top. PERFORMANCE TESTS
PC Magazine Australia Labs performed extensive throughput and interoperability testing of the products we reviewed. We found that with a little tinkering, all of these products are interoperable at the highest levels of encryption supported. Though there are some performance differences among the products, we found that the access points are fairly consistent no matter whose client is in use. Building on its reputation for fast wireless performance, the Cisco Aironet 350 Series performed best among the 802.11b products reviewed. Cisco attributes its success to a faster access point processor, improved antenna sensitivity, and tight control at the MAC sublayer. Closer examination of the performance numbers uncovered a disturbing trend: two clients contributed about 92 percent (5.8Mbps/ 6.28Mbps) of the total load, while the other two contributed little. The other products tested showed roughly equal throughput to all four clients. Some performance difference can be attributed to environmental and location differences, but Cisco suspects the poor card performance is due mainly to faulty beta hardware. We could not verify this claim in time for this review. As we expected, the 3Com AirConnect 11Mbps Wireless LAN Solution and Intel PRO/Wireless 2011 LAN Solution performed similarly; they are both manufactured by Symbol Technologies. The other Symbol product, the Ericsson Wireless LAN 11Mbps DSSS, achieved only 83 percent of the Intel product's score. The use of AP firmware, client firmware, and driver versions older than those employed by the Intel or 3Com products is the likely culprit.
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Our Editors' Choice, the Lucent Orinoco AP-1000, showed mediocre performance. Anecdotal testing indicates that it suffers greater performance degradation with WEP encryption enabled (16.8 percent degradation) than does the Aironet 350 (0 percent) and the Symbol Technologies products (the 3Com, for example, suffered only a 9.4 percent degradation). According to Lucent, the Orinoco AP-1000 will show this behaviour at high loads and when connected to the clients at the 11Mbps rate. The 40-bit consumer-class product, the D-Link DWL-1000AP, showed the highest throughput.
We performed extensive interoperability tests among all vendors at the highest possible level of encryption. After some modifications, we achieved encrypted wireless communications in all products tested. Additional details on testing as well as our extensive interoperability throughput performance results and analysis may be found in our online edition. To measure throughput, we used Chariot 3.2 from NetIQ (www.netiq.com) and its filesndl test suite, with the clients simultaneously downloading uncompressible data from the server for a two-minute interval. The scores shown depict the mean of three consecutive tests.
In the small-office category the decision was much easier. The D-Link DWL-1000AP and wireless PC Cards were clearly the best in this category. We found the D-Link access point to be the best-engineered, best-designed, and top-performing product we reviewed. The D-Link access point also contained the most feature-rich products, and it's the least expensive. And finally, the D-Link product offers centralised management for multiple APs, as well as excellent and fast installation software.
Cisco Aironet 350 Series
The Cisco Aironet 350 Series has flexible management options, good integration with Cisco infrastructure products, and several unique features. Also, updating firmware is much easier with the Aironet 350 than with any of the other products reviewed, and this can be accomplished from a local file or directly over the Web.
Among the Aironet 350's unique features is a hot-standby mode that offers redundancy protection for failed access points. Also, only the Aironet 350 can be adjusted to limit the size of a given access point's coverage area, known as a cell.
The Aironet Client Utility (ACU) presents real-time statistics, monitors system status, has a diagnostic link test, and helps administrators perform a basic site survey. But its capabilities are limited compared to the products manufactured by Symbol Technologies and the Lucent Technologies enterprise product.
The Aironet 350 doesn't replace the Aironet 340 we reviewed last year, but rather it includes features focused on larger enterprises needing more scalability and stronger security.
Combining other Cisco products with the Aironet 350--specifically the ACS2000 server, LEAP technology, and the RADIUS server--administrators can manage wireless user accounts and centrally create and distribute wep keys on the fly. Configuring the Aironet 350 to authenticate to a radius server, however, required a good bit of troubleshooting and a firmware upgrade. This setup allows easy authentication of clients but is not interoperable with client cards from other vendors.
The Aironet 350 was our top performer, averaging 6.28Mbps throughput using 128-bit encryption, but we did find some strange anomalies. The AP periodically suffered brief connectivity drops, possibly due to beta hardware. When we tested with two PC Cards, performance was impressive. But as we added more PC Cards to the mix, performance of those additional cards degraded significantly. We suspect that faulty capacitor on some of the beta cards may be to blame.
Cisco Aironet 350 Series"
Intermec 2102 Corporate Access Point
The Intermec 2102 Corporate Access Point is the company's low-end product, but it competes with the other corporate-class products in our roundup. The Intermec 2102 is fully compliant with the 802.11b standard, and it is also compatible with the Proxim OpenAir wireless networking standard, making the Intermec 2102 a good choice for companies moving from OpenAir to 802.11b.
The Intermec 2102's rear panel provides connections for 10Base-T Ethernet, an external power supply, and an RS-232C serial connector. The serial connector is used to perform the initial configuration, but unfortunately, you must purchase a 9-pin-to-9-pin null modem cable separately in order to set up the Intermec 2102.
A significant oversight by Intermec is the absence of survey and placement tools. But once you've set the unit's IP address using the serial interface, you can configure the Intermec 2102 via the serial port, telnet, browser interface, or via a third-party SNMP management console. Experienced administrators will probably not mind the tedious aspects of Intermec's setup experience, such as the three steps needed to alter your initial settings, which includes "saving", "storing", and "committing" to any changes.
Like several other vendors in our review, Intermec repackages the Lucent Orinoco World PC Cards (and client management software) as part of its product line (see next section).
The Intermec 2102 includes several features that make it easier to operate and manage very large wireless LANs. Most important of these is IP tunnelling, which allows users to roam across access points connected to multiple Ethernet switches and routers while maintaining a single client IP address. The Intermec 2102 also allows administrators to update the firmware in all the APs on the LAN from a central location.
Despite shortcomings in survey placement and reporting, the Intermec 2102 performed well in our aggregate throughput performance testing, offering 5.08Mbps, second only to the Cisco Aironet Wireless 350 Series.
Intermec 2102 Corporate Access Point
Lucent Orinoco AP-1000
The Lucent Orinoco product line is the latest incarnation of one of the oldest wireless products on the market. Originally introduced as the WaveLAN WavePoint II, the Lucent Orinoco AP-1000 features a simple user interface, dual radio capability, and excellent diagnostic tools. Lucent offers two versions of the Orinoco World PC Card; the Silver version provides 64-bit encryption, and the Gold version provides 128-bit encryption. Both cards use the same client software, which includes a suite of best-in-class diagnostic and configuration tools. These features in combination helped us in our tough decision to award Lucent an Editors' Choice.
Housed in a flat metal box, the Orinoco AP-1000 has two PC Card slots, a 10/100 Ethernet interface, and a set of four indicator LEDs. The PC Card slots hold one or two Orinoco wireless cards. Lucent also offers a wireless backbone option that allows several Orinoco AP-1000s to communicate with each other via radio, with no Ethernet backbone. This is useful in large areas such as warehouses or retail stores because you can expand the wireless network without running additional cables.
Using Lucent's Windows-based Orinoco AP Manager software, installation and configuration took about ten minutes, making this one of the easiest-to-configure products in our roundup. The AP Manager includes a complete set of diagnostic and signal measurement tools. Lucent also provides an HP OpenView plug-in that allows remote management of multiple Orinoco AP-1000s.
Lucent's client software is easy to install, and it provides some of the best diagnostic and configuration tools of any of the products we tested. When active, the driver displays a small bar-graph signal-strength indicator on the tasktray. A right mouse click on the icon brings up a configuration menu that lets users choose from up to four predefined configuration sets; each set can have its own System ID and WEP key.
This is a great feature for people who move among several wireless LANs, since it allows instant reconfiguration on the fly, with no rebooting required.
The Lucent Client Configuration Manager--also accessible from the tasktray icon--provides tools to manage the predefined configurations. While its throughput performance was lacklustre at 4.24Mbps (as compared with the Cisco Aironet 350's 6.28Mbps) the Orinoco AP-1000's many other superb features still allowed it to shine.
Lucent Orinoco AP-1000
Ericsson Wireless LAN 11Mbps DSSS, Intel PRO/Wireless 2011 LAN Solution, 3Com AirConnect 11Mbps Wireless LAN Solution
For this story, we acquired wireless LAN solutions from Ericsson, Intel, and 3Com. On further inspection, we discovered that the products were virtually identical in terms of hardware architecture, software, and performance. All three use chip sets from Intersil, and each manufacturer has (or had) a research and development agreement with Symbol Technologies, the original maker of these products. Because of the three products' similarity, we reviewed them together and noted the few differentiating features among them.
We found the setup process of these products a little more cumbersome than that of the Cisco Aironet 350 Series and the Lucent Orinoco AP-1000. The Ericsson, Intel, and 3Com products required initial configuration via a null modem cable between a PC and the access point. We then used HyperTerminal to assign the AP an IP address.
Each product was up and running in about 15 minutes. Once the access point was configured, we were able to access the administrative interface with a standard Web browser. Access points also can be managed via direct serial connection or telnet. Installing the NIC drivers on our client laptops was simple: both Microsoft Windows 2000 and Windows 98 automatically recognised the wireless PC Cards. Finally, drivers were quickly pulled off the accompanying CD, an SSID was assigned, and the installation was complete.
The three vendors provided virtually identical software utilities, though the utilities were renamed. A site survey application runs a series of tests to determine optimal placement of access points throughout an organisation. The application then produces a canned report that summarises the information.
The client software utilities let users monitor signal strength in real time, adjust power management settings, and auto-discover networked access points. Users can modify the power management slider bar to set the optimal ratio of power used versus speed. There are also utilities to upgrade the NIC's firmware, perform diagnostic tests (such as a ping test), and monitor current system status. The NIC firmware can be updated directly from a local file, although we'd like to see a direct link to the manufacturer's Web site for easier updating.
Ericsson's and Intel's client software implementations are virtually identical. 3Com has slightly modified its offering by adding a launcher applet that provides access to the same information, but in separate windows.
Upgrading of firmware on each vendor's access point could use some refinement. Firmware must be updated using a TFTP server or Xmodem software. In contrast, the Cisco Aironet 350 can update AP firmware directly over the Web. All the companies in the enterprise class stated that software to enable automatic updating is in development for release this year or next. Similar to the Cisco Aironet 350, the AP firmware update and configuration settings can be centrally deployed to other remote access points simultaneously, though they must reside in the same subnet. Since none of the vendors support remote flashing of client NIC firmware, it must be done manually.
All three products support both 40-bit WEP and 128-bit encryption levels. The 3Com AirConnect also supports two different Layer 3 security solutions for enhanced security: one based on MPPE and the other based on IPSec.
Ericsson also has a high-security feature called WLAN Guard. It uses ISAKMP/IKE for authentication and key negotiation and IPSec for authentication and data transmission.
The Web-based administrative interface is relatively easy to navigate. There are capabilities to monitor system status in real time, adjust security levels, and manage mobile units. The Ericsson, Intel, and 3Com products, however, lack the failover capabilities of the Cisco Aironet 350.
The manufacturers have added SNMP support to the access points, allowing standard network management platforms, such as HP OpenView or Tivoli IT Director, to query and log the APs. The AirConnect, for example, can also be used with 3Com's Transcend Network Supervisor, which plugs into various management platforms. In contrast, Intel offers the WNMS (Wired Network Management Software) to centrally manage APs and clients.
Only 3Com offers a Power-over-Ethernet adaptor in the box. The adaptor is an option with the Ericsson and Intel solutions.
As expected, we found similar performance among the three products. The 3Com and Intel wireless networks transferred data at 4.52 and 4.55Mbps, respectively, (as compared with 6.28Mbps from the leader, the Cisco Aironet 350). The Ericsson managed just 3.8Mbps using 128-bit encryption. This could be due to Ericsson's use of an older firmware revision than the other two solutions.
Interoperability throughput was generally as advertised, although there were a few exceptions. The Intel product and 3Com AirConnect performed well with the Cisco Aironet 350; the Ericsson product managed to sustain only a 1Mbps connection, though this also could be due to the product's older firmware. We also needed to change several default access point settings before connecting properly with the Lucent-based products (from Intermec Technologies as well as Lucent) and the D-Link and Linksys networks.
Ericsson Wireless LAN 11Mbps DSSS
Intel PRO/Wireless 2011 LAN Solution
3Com AirConnect 11Mbps Wireless LAN Solution
D-Link DWL-1000AP
D-Link Systems offers a broad range of wireless networking products designed specifically for the home and small-office marketplace. Despite this product focus, D-Link provides centralised management for multiple access points, a feature usually found only in high-end offerings aimed at corporate customers. Thanks to this and its impressive performance, D-Link gets our Editors' Choice award.
We tested the D-Link DWL-1000AP, the DWL-650 Wireless PC Card, and the DWL-120 USB Network Adaptor, the first USB-connected wireless adaptor we've seen. The company is expected to start shipping the DI-713 Wireless Router and Access Point, which combines a wireless AP, Ethernet switch, and IP router in one package.
The DWL-1000AP is packaged in a small plastic case about the size of a Zip drive. The DWL-1000AP also has a single, swivelling antenna that can be adjusted for optimal placement. The AP manager software can operate over wired or wireless LANs, and a single copy of the AP manager can control multiple access points. Initial installation takes only a few minutes, and the settings can be saved to a disk file as a backup or as a starting point to configure additional APs.
D-Link's PC Card client software is nearly identical to and provides the same features as the Linksys product. Both appear to have been developed by the same company, but D-Link's installation software is easier to use.
Several companies promised to deliver a USB wireless adaptor in time for our review, but D-Link was the only company that made good on the promise. USB adaptors let people create an all-wireless home LAN. D-Link's USB adaptor is easy to install, though it currently lacks a site-survey tool or configuration tool.
D-Link DWL-1000AP
Linksys Instant Wireless WAP11
Linksys--like archrival D-Link Systems--was one of the first companies to see the need for networking products designed for the home and small office. The company's new Instant Wireless product line offers exactly what we've come to expect from Linksys: a very functional, no-frills product at an attractive price.
The Linksys Instant Wireless product line includes two access points (with and without a built-in cable/DSL router), a PC Card wireless network adaptor, and a PCI bus adaptor that lets you use the wireless PC Card in a desktop PC. We tested the Linksys WAP11 Access Point and the Linksys WPC11 Wireless Network PC Card.
The Linksys access point is housed in an attractive purple and black plastic case that is designed to stack with other Linksys components, particularly with the company's popular EtherFast cable/DSL router. The WAP11 features dual antennas that provide a larger coverage area and better protection from "dead spots" than the single antenna used by most of the small-office access points we tested. Unique to the WAP11 is a clever usb-based setup and management system that allowed us to get the WAP11 set up and working within 10 minutes of opening the box. The setup software isn't pretty, and the screens don't match the examples in the manual, but most users will only need to run the software once.
The software for the WPC11 Wireless Network PC Card includes drivers for Microsoft Windows (all versions) and a site-survey/diagnostic tool. Installation is the typical plug and play, but we encountered a small glitch when trying to connect our test laptop to the WAP11. The PC Card drivers defaulted to Ad-Hoc network mode, which is only useful in a PC-to-PC network environment; we had to manually switch the driver to Infrastructure mode to communicate with the access point. Fortunately, the Linksys client configuration tool lets users change the driver settings without rebooting the system. The client software also includes basic signal-strength and link-quality meters.
The Linksys access point scored 4.53Mbps on our throughput test, giving it the second-best throughput in the small-office category. Linksys provides free software updates via its Web site. Despite a few installation hiccups, we think this is a good system for home and small-office use.
Linksys Instant Wireless WAP11
Lucent Orinoco RG-1000
The Lucent Orinoco RG-1000 combines an 802.11b wireless access point, a network-address-translation-capable IP router, and a V.90 modem. The Orinoco RG-1000 can be used with conventional dial-up ISP connections, or to share a broadband DSL or cable modem connection.
The Orinoco RG-1000 is housed in a sleek sliver-grey plastic case that stands upright on a desktop (and also comes with fittings for wall mounting). A cable cover hides the connectors on the rear panel, allowing a neat installation. A single CD-ROM contains installers for both the client software and the Orinoco RG-1000 setup program. The Orinoco RG-1000 must be configured from a wireless laptop, so the setup wizard first guides you through the client software installation. The client software is identical to the software provided with Lucent's enterprise-class products; it includes the same excellent diagnostic and configuration tools, including the ability to switch wireless profiles on the fly.
We configured the Orinoco RG-1000 to work with a DSL connection, and we also tested it with a MindSpring dial-up account. Both worked flawlessly. When you use the Orinoco RG-1000 with a dial-up connection, the client software shows an animated modem icon on the tasktray to let you know you're connected.
Although the Orinoco RG-1000 is designed for the home market, it can also be configured to operate as a standard wireless AP on a wired LAN. The Orinoco RG-1000 can obtain an IP address from a DHCP client, and it acts as a DHCP server for wireless clients. This arrangement allows the Orinoco RG-1000 to serve multiple wireless clients while using only a single IP address on the LAN. The low marks the Orinoco RG-1000 received for AP survey and placement and ongoing management are a reflection of our comparing it to the small-office-focused products, where these tools become more relevant than with use in the home.
Lucent Orinoco RG-1000
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Lucent Orinoco AP-1000
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