The Case for Voice over WLAN
March 11, 2002
Here is a business case in which implementing voice over WLAN made sense, and is paying off in terms of costs and efficiencies.
Voice over WLAN, an application with a high gee-whiz quotient if nothing else, has yet to really capture the imaginations of enterprise users, or vendors for that matter.
The reasons are perhaps not hard to find. The case for running voice over a 100-Mbps fast Ethernet wired LAN is not difficult to make.
In most such environments, there is bandwidth to spare. Voice over LAN promises significant cost savings on moves, adds and changes, very sophisticated user-programmable customization features - and IT personnel only have to support one network infrastructure.
Making room for voice on an 11-Mbps wireless LAN is another matter altogether. And how many companies looking for a new phone system have an entirely wireless LAN infrastructure?
But where there is a strong case for integrating voice and data on the same network and a need for mobility, voice over WLAN suddenly pops out as the obvious solution.
That's what Gate Gourmet Switzerland, an airline catering company in Zurich, Switzerland, concluded. Eighteen months ago, the company implemented a voice over Wi-Fi system using equipment from Holtsville, NY-based Symbol Technologies.
Gate Gourmet manager of logistics and systems Renato Gianola says the system, which includes 36 Wi-Fi access points, Symbol's Spectrum24 NetVision voice solution, and 70 Symbol NetVision Phones and Data Phones, is "absolutely unique."
It lets dispatchers keep precise track of the packing and unpacking of the high-loader trucks the company uses to deliver meals and drinks to aircraft on the runway.
That tighter control translates into a 70-percent reduction in delivery delays, and a resulting decrease in penalties Gate Gourmet has to pay when it holds up an aircraft's take off.
"We said at the beginning that we would have the whole system paid back in two years," Gaianola says. "That means by the middle of this year. And yes, we will pay it off."
The other obvious bottom-line benefit falls out of overall process efficiencies. Gate Gourmet found it was able to reduce the number of dispatchers it has on duty at peak periods. This amounts to a saving of two full-time equivalents a year.
Gate Gourmet production planners receive details of flight requirements from the airlines. The company handles all Swissair flights and other airlines' business as well, a total of 250 flights a day at Zurich.
At the 30,000-square-meter, five-story facility Gate Gourmet moved into at the Zurich International Airport in mid-2000, the food and drink is assembled in one area and then sent in trolleys to the loading docks to be packed on the high-loaders.
Dispatchers are the go-betweens who talk to production planning, assembly areas, and the loading dock, controlling the whole process.
Before implementing the voice over Wi-Fi system, Gate Gourmet used CB radios, human eyeballs, and typed lists to ensure the right stuff got on the right truck and that it left on time.
If shipping dock employees or drivers needed to confirm details with dispatchers or report problems, they used the CB radios. But voice quality was poor.
"We had a lot of miscommunication," Gianola says. "You always had to ask the other person two or three times, 'What did you say?' So we tried to avoid using voice."
For the most part, the company relied on employees on the docks to carefully check shipping lists and make sure that everything was loaded on the truck before it set out for the aircraft.
"But you never got certainty that it was correct," Gianola explains. "Nobody went into the truck to recount. It was all based on guessing - or hoping - that everything was okay.""The first time you really realized [the shipment] was not complete was on the aircraft. And most of the time it was too late then. Or it was very expensive to deliver [what was missing] at the last minute by car."
Gate Gourmet experimented briefly with using 900MHz cordless phones to solve the voice communications problems, but found the cost of covering its facility with base stations was mushrooming.
It was then that Gianola lit on the idea of integrating voice and data on an 802.11 network. The company was already coming to the conclusion that it needed to automate the whole dispatch, loading, and delivery process.
This was a way to do it. And systems integrator PEAK Technologies (Schweiz) AG (www.peakeurope.com) offered a deal Gate Gourmet couldn't refuse.
PEAK is the Swiss subsidiary of a Moore Corp. company that specializes in supply chain execution solutions. It already had experience installing 802.11 data networks and was eager to try a voice implementation using the Symbol products. So it waived some of its consulting and systems integration fees. Total cost for the system to Gate Gourmet was less than $500,000.
The system PEAK designed goes well beyond just solving the voice problem. Now dispatchers sit in front of a computer screen. Production planners transmit jobs to the dispatchers, who relay them to shippers.
Shipping dock employees and drivers now carry Symbol NetVision Data Phones. The Data Phones combine voice telephony, text messaging, voice intercom, data capture and bar code scanning, and they have an embedded thin client and Wi-Fi radio.
The food and drink boxes coming from the assembly area are now bar coded. The whole process to get a consignment from the Gate Gourmet facility onto the aircraft requires eight separate steps. At each step an employee scans a bar code to send confirmation that the step is complete.
So the dispatcher always knows at a glance the exact status of any job. And trucks are not released from the dock until the consignment is confirmed to be completely loaded. At the aircraft, employees continue to scan bar codes to confirm completion of each step.
Outside the Gate Gourmet facility, the data goes over an 802.11 network the airport authority installed. The airport is trying to make its wireless network a money maker and charges users like Gate Gourmet by the bit transmitted.
Because the usage rates are actually fairly steep, the company avoids using voice as much as possible outside its own building. Another problem is that to use voice over the airport network, users have to first reconfigure their phones from the indoor settings.
So voice only gets used in real emergencies - "if the truck runs in to the aircraft, for example" Gianola deadpans. And even some emergency communications are by data.
Employees carry a sheet with bar codes for frequently encountered problem situations - no power to the aircraft's loading door, for example. They scan the appropriate code and the dispatcher knows immediately what is happening and can take action.
As well as the 20 NetView Data Phones used on the shipping dock and 40 used by employees on the trucks, there are also 10 NetView Phones used by managers and supervisors who move around the facility and need to be accessible wherever they go.
Those phones connect to the PSTN through a gateway/gatekeeper and have an outside number. The rest of the NetVision phones are only used internally. Callers reach them by inputting an IP address. The phones still ring in the normal way, however.
Because employees can now use the NetVision phones for all internal voice communications, Gate Gourmet was able to save more money by eliminating some wired phones with outside phone company lines.
Gianola is high on PEAK, the company that implemented the system. Finding a partner that knows what it's doing is a key to making a project like this work, he says. And it worked better even than he dreamed.
"Believe it or not, the whole implementation was smooth as silk," he says. "It was amazing for all of us."
Even getting buy-in from employees and training them was easier than expected, Gianola says. They were all familiar with cell phones and the NetVision phones worked much the same way.
PEAK made sure network coverage was 100 percent in the crucial areas, building in lots of access point redundancy. Now the company is extending coverage to the rest of the public areas in the building.
Voice over WLAN may not make sense in a lot of cases, but in some it will. Clearly Gate Gourmet is one.