Wireless LANs come of age

Whether you like it or not, information systems are a pervasive element of today's workplace. From e-mail to parcel shipping, there is a plethora of applications ready to meet most business needs.


Whether you like it or not, information systems are a pervasive element of today's workplace. From e-mail to parcel shipping, there is a plethora of applications ready to meet most business needs. Computer workstations populate nearly every niche of the workplace. Sometimes it seems that there are more PCs than there are people.

While the purposes of these systems differ, they generally have one element in common - a lot of wires. If the computer revolution has produced vast benefits for society in general, it has been a bonanza for cable manufacturers. It has also been a bit of a pain for plant engineers who are usually responsible for cable installation and maintenance.

Category 5 twisted-pair (Cat-5) cabling is the interstate highway system of computer networks. It connects computer workstations, printers, and servers. Walk a factory floor or tour an office building and you'll see plenty of them. Like any pest, for every piece you see in the open, there are tons buried out of sight.

Running cables can be an expensive proposition. Walls, floors, equipment, and distance can conspire to make cabling a challenge. It's a never-ending saga. Even in the most "wired" facility, there seems to be a need to put a workstation in a place not covered by cabling. We value mobility and responsiveness, yet our computer networks anchor us.

While we weren't born with the wired fetters of the computer age, until recently they have been a fact of life. However, recent advances in technology and standards provide the promise of freedom from the shackles of wire. Wireless local area networks (LANs) have come of age.

New standard changes wireless

Wireless LANs aren't new. Wireless, or radio frequency (RF) communication, has been successfully supporting business applications for more than a decade. But its use has been restricted to specialty applications, such as warehouse management systems. Relatively low speeds, high costs, and proprietary standards inhibited its general use in the workplace. Wireless did not provide the bandwidth or speed to support most applications. And it required proprietary hardware and software that drove up its installation and administrative costs.

The emergence of the IEEE 802.11b high-rate standard has changed wireless communications. Networks based on this standard provide transmission speeds of up to 11 Mbits/sec. This rate is more than five times faster than the previous wireless LAN generation. It is also comparable to the speed of many "hard-wired" LAN connections.

Speed is only part of the equation. Vendors have developed tool sets that greatly simplify network installation, configuration, and management. What was previously the domain of outside specialists can now be handled by an internal IT department. In an arena dominated by proprietary technology, interoperability is now the watchword. No longer are wireless customers tied to one vendor. Wireless components purchased from different vendors operate together on the same LAN, provided they are "Wi-Fi" compliant as defined by the Wireless Ethernet Compatibility Alliance (WEAC).

Wireless LANs tie devices together through RF-enabled network cards and access points. Like their wired cousins, wireless network cards are available for notebooks (PCMCIA) or desktop (PCI) PCs. Access points are basically wireless switches sending and receiving data from multiple devices in their coverage area. Access points are typically wired into a high-speed cabled backbone. They are usually found on ceilings or walls, providing coverage to PCs within a 300-400-ft radius. Wireless PCs in the network are not tied to one location or access point. As they are moved through a facility, they automatically link to the access point that provides the strongest signal.

Wireless network cards and access points cost more than their wired counterparts. But in certain situations, this cost differential can evaporate - or even flip-flop - when the cost of installing cable is included. If you are looking to put a small PC network in your den, wireless isn't going to be cost effective. But if you need to network PCs in an old plaster-wall building or on a high-clearance factory floor, you may find wireless is the cheaper route.

Networking vendors provide wireless solutions

Computer and networking vendors are beginning to fervently push wireless solutions. They obviously see a bright future in wireless. Vendors like Dell, IBM, and 3Com have even begun producing television commercials pitching their wireless product lines. This faith is not misplaced. Demand for networked devices is only going to grow. While traditional cabled networks will continue to meet some of this demand, more and more of these devices are going to be mobile or in hard-to-wire places.

Wireless communication has been an evolutionary process in the computer industry. Most wireless LAN vendors have gotten their starts elsewhere. As a leading supplier of automatic identification solutions, Symbol Technologies (symbol.com) has long been known for wireless equipment as well as bar code scanners. Its Spectrum One RF product line has been providing wireless communications between portable data terminals and host computer systems for more than a decade. But, these data terminals are basically DOS-based machines with small area, character-based displays. Applications must be custom developed for these devices or use VT-100, IBM 5250, or some other type of data terminal emulation. Spectrum One also doesn't provide the speed required for most standard LAN-based applications.

Last year, Symbol introduced a new generation wireless product line - Spectrum24 High Rate Wireless LAN. Based on the 802.11b standard, Spectrum24 offers the speed needed for many business applications. Its network cards and access points can be mixed and matched with other vendors' 802.11b products. Its SpectrumSoft management software simplifies network setup and administration.

Symbol also sees Spectrum24 providing the infrastructure for in-building voice communications. Its voice-over-IP services allow the network to serve as both a voice and data backbone. With its NetVision Data Phone, Symbol also believes that voice and data services will converge into one end-user device.

Since the early days of commercial LANs, 3Com Corp. (3com.com) has been a prominent supplier of Ethernet networking solutions. Its network cards, hubs, and switches are found in offices, manufacturing plants, warehouses, and just about every other place where LANs are employed. With the advent of the 802.11b standard, 3Com has supplemented its networking solutions with AirConnect, a high-speed wireless LAN.

AirConnect components include network cards for notebooks, desktops, access points, and management tools. A Wi-Fi certification ensures that AirConnect network cards and access points can operate in multivendor environments. Web-based configuration and management tools allow IT departments to deploy and administer wireless LANs without resorting to expensive outside consultants.

One really nice aspect of AirConnect is its PowerBASE-T module, which eliminates the need to connect access points to an ac power outlet. This module converts ac to low voltage dc power, which is transmitted over a Cat-5 backbone. Access points connected to the backbone don't need a separate AC power source.

Through products like Spectrum24 and AirConnect, wireless LANs are definitely going to make their mark in the workplace. How fast depends on how quickly end-users and IT departments embrace a wireless mindset. The cost of cabling is only one side of the equation. Flexibility and mobility are also major drivers.

Plant engineering departments need to get on this bandwagon. Wireless LANs provide a way to deploy or extend production and maintenance systems to places that can't economically be reached with cabling. They make it easy to reconfigure workstations to meet ever-changing demands. They provide the communications backbone for a new generation of handheld and mobile devices that are rapidly making their way into every niche of the workplace. Hopping on the bandwagon now will pay substantial dividends in the not-too-distant future.

Tom Singer is an information technology consultant who specializes in designing, developing, and implementing systems solutions that meet client operational needs. He has worked as a developer and integrator of CMMS solutions. He is a principal of Tompkins Associates, a total operation consulting firm headquartered in Raleigh, NC. He can be contacted at 630-472-1524, or by e-mail at tsinger@tompkinsinc.com . Previously published "Information Engineering" columns are available on our web site: plantengineering.com.

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