Wireless LAN Technology

Wireless LAN technology has been around for some time now, but it has largely been confined to vertical markets. Health care, restaurant and retail, warehouse and manufacturing, and utilities are some of the segments in which wireless LANs have found traction. In the health care segment, for example, wireless LANs have proved their value by increasing productivity in areas such as patient check-in and billing.

Enterprise use of wireless LAN technology, however, has been a bit more problematic. For many years, the technology has been viewed as a specific niche or problem solver, rather than as a broad-based horizontal solution. Wireless LANs were considered ideal for temporary offices or for use in places where wireline technology was impractical, such as historic buildings. For quite some time now, many have wondered about what was needed to bring wireless LAN technology into general usage.

The first problem to be overcome had to do with defining a real market need. Simply put, there must be some compelling reason to invest in this technology and deploy it throughout an enterprise, when most workers are already wireline-connected to their LANs. Ironically, the justification for this incremental investment is found in one of the earliest envisioned applications for wireless LAN technology, namely, roaming.

Unlike the way a wireless LAN is used in a vertical segment, where it is often the dominant LAN technology in use, practical enterprise roaming is made possible by the judicious combination of both wireline and wireless technologies. By installing wireless antennas in conference room areas, workers can bring their laptops into meeting rooms and collaborate. But more important, by also installing antennas in office areas, workers visiting these places can connect to their home network as well. They have instantaneous access to their documents, e-mail and spreadsheets, enabling them to work without disadvantage alongside their colleagues who are wireline-connected to their servers. With wireless LAN access, visitors no longer need to waste time loading up a laptop disk drive with every conceivable document that might be of importance in a meeting, or suffer the frustration when one of these documents is left behind.

Technical problems also stood in the way of the widespread use of wireless LAN technology. But over time, suppliers have been addressing these issues one by one. For example, roaming is a very sophisticated capability, from a networking perspective. Packets sent by a mobile user, for example, must find their way through the network back to the server. And in reverse, packets from a server -- e-mail, for example -- must find their way through the same network to the mobile user, wherever he or she might be. Early on, suppliers solved this complex problem by developing MobileIP.

With the IEEE 802.11 multivendor wireless standard, suppliers solved another significant technical problem. For most of its existence, wireless LAN equipment was strictly proprietary. Multivendor support -- the ability to mix and match equipment from different suppliers -- was simply not possible. With the IEEE 802.11 standard in place, suppliers have overcome this limitation. It is now safe to buy and integrate equipment from different suppliers into one composite wireless LAN solution.

Although many companies now offer products based on the 802.11 standard, not all can be considered equal. Most of these suppliers are small, and they focus almost exclusively on this one technology. There are advantages to be gained by considering equipment from a larger company. Suppliers in this category can offer benefits that are beyond the capability of smaller, single-product companies. For example, a large networking equipment provider will also have a scalable product line of L2 and L3 switches. These companies can guarantee that the adjunct wireless LAN network works flawlessly with all of the equipment in the wireline infrastructure. Additionally, these companies can offer network management products that seamlessly manage both the wireline and wireless networks and their components. Finally, a large company is better positioned to offer national and global service and support for the installation and maintenance of the wireless LAN equipment.

Cabletron Systems (Rochester, N.H.) is a company that falls into this large-supplier profile. As a result of its acquisition of Digital Equipment Corp's Network Products Group, Cabletron got access to a stellar array of wireless LAN technology. Back in the early 1990s, Digital invested heavily in this technology and, as a result, was a true market leader in wireless LANs. The good news is that Cabletron has made the decision to invest in, champion and expand the work done by Digital.

If smaller companies are to your taste, there is a wide range of suppliers with whom to work. Aironet Wireless Communications Inc., Breeze Wireless Communications Inc. and Proxim Inc. are just some of the companies who are members of WLANA, the wireless LAN alliance. --Sam Alunni is vice president of networking at Sterling Research (Sterling, Mass.). Contact him at alunni@sterlingresearch.com.