While the implementation cost of a WLAN can often be higher than a wired network, in some situations, a WLAN can be less expensive and can actually reduce networking expenses over time. This is especially true for enterprises anticipating rapid personnel growth and frequent office reconfigurations.
TechRepublic member Chris Green, a senior network support specialist at a Toronto-based automotive electronics manufacturer, said that a wireless network he installed will save the company at least $3,200 per year on the cost of recabling and renetworking machines on the factory floor. That savings increases if you consider the potential cost of a certified cable technician, who could easily spend five or more hours running cables for each machine across a 40-foot ceiling and back to a switch closet 150 feet away. Green, however, did use a cabling technician, so the savings likely would have been higher, he said.
How WLANs save manufacturers money
What makes a WLAN an appropriate solution for Green’s company is the amount of change that takes place within a factory environment. Companies intent on keeping industry QS-9000 and ISO 9001 certifications up to par have to regularly streamline processes and increase throughput on the manufacturing lines. This often means moving existing machines or adding new ones—but unfortunately, when the machines move, the network has to move too.
In any given year at Green’s company, as many as 20 networked machines might be moved and need recabling. Changing a wired network so frequently is not only costly, but it also runs the risk of creating a rat’s nest of wires. That obviously can’t happen with a wireless network.
Along with saving money on a cost-per-port basis, a WLAN also boosts uptime on the manufacturing floor. Because of the redundancy in the access-point coverage, the machines can be placed virtually anywhere within the 85,000-square-foot building and still access the network.
Eliminating the headaches inherent with LANs obviously helps the IT workload as well, Green pointed out.
“In automotive, with a rigid just-in-time inventory and supply chain management constraints, downtime is the biggest enemy,” explained Green. “Late shipments are penalized heavily. And you never want them as a result of your IT department, which is a non-revenue-generating department.”
Trimming the WLAN budget
The final cost for Green’s WLAN implementation was about $22,400—$3,200 less than the $25,600 estimate for installing a wired LAN. Green did, however, have to cut a few Cisco wireless Ethernet cards out of the project budget to bring the project in under the cost of a wired LAN. The IT department will now pull in cheaper Linksys USB cards as a budget expense item, rather than a capital expense—a long approval process where Green works.
In his initial budget, Green included an upgrade for the antennae on six Cisco 340 access points. According to Green, the antennae that ship with the Cisco 340s had reception from 2 to 4 db. So Green chose replacement antennae with 13-db capabilities to allow for a 1 to 1.5-db signal loss over cables and connectors. He also made certain that the antennae had a suitable footprint to penetrate an oddly placed six-inch cement wall on the manufacturing floor. This would have been impossible with OEM antennae, he said.
Rather than having internal staff handle the physical installation and antennae configuration, Green relied on the expertise of a cabling contractor.
“They know our building better than anyone, and they have an excellent understanding of antennae configuration,” he explained.
While a cabling contractor is typically an expense saved in most WLAN efforts, Green said it was worth it in his situation, as it would have cost more for internal staff to do the work, in terms of hours away from other, more critical projects.
“The rule of thumb is that if you are using one access point for a small area, do it yourself,” he said. “Otherwise, find a knowledgeable partner that knows about wireless and has purchasing contacts regarding antennae.”