While vendors debate the way to Wi-Fi and cellular services, and the right way to manage and secure wireless access points, Lehman Brother in New York has picked up a novel idea. The company added its own cellular base station, and distributed the signals by fibre-optics to radio aerials throughout the building. And now, by adding Wi-Fi to the same system, it believes it has solved Wi-Fi security issues by keeping its access points under lock and key.

The global investment bank wanted better cellular coverage for workers who use cell phones BlackBerry PDA-style voice/data devices (BlackBerry review), so it turned to MobileAccess Networks, a company which sells specialised cabling plant to distribute wireless signals inside buildings.

The need arose when some departments within Lehman Brothers took up residence in a new building in metropolitan New Jersey. The construction - particularly the reflective glass used - tends to distort signals, explains Ed Coffey, vice president of mobile engineering.

Once the MobileAccess system was in place, the company got better cellphone coverage by placing the MobileAccess aerials where they were needed. Then it decided it could also use the platform to condition and distribute its Cisco-based wireless LAN (Wi-Fi) signals, using a newly launched Wi-Fi module, the MA-850. The two goals were to save on operational costs and improve security, Coffey explains.

Put your APs in a closet
MobileAccess takes the interesting approach of locking physical access points (APs) in a telecom closet. It neatly overturns the old arguments about thin versus fat access points by providing its own antennas, which are distributed around the building, Coffey explains. "This means APs are in a secure place. Also, you can tune the power levels of each antenna to the edge of a window so they're not blasting signals outside."

Operationally, he says that every time he wants to add APs, he won't have to drag them around the building to install them; rather, they get installed in the wiring closet.

An "RF switch" from MobileAccess allows any AP to communicate with any Wi-Fi antenna. This means the company needs only a few extra access point in the wiring closet, rather than installing large numbers in ceilings in case any one should fail, says Jeff Kunst, MobileAccess vice president of marketing.

Centralising the access points allows users to apply "N+1 redundancy", a proven, cost-effective method of backing up network hardware to protect against downtime. Instead of requiring a back-up for every AP, which can become quite expensive, just one extra AP per "n" number of APs can simply be installed in the wiring closet. Should an AP fail, the extra AP can automatically kick into action. The MobileAccess RF switch will associate that back-up AP with whichever antenna in the building requires it, explains Kunst.

The MobileAccess infrastructure propagates a variety of wireless signals throughout a building using a combination of coax and fiber. Wireless signals are picked up and delivered very near the wireless parties via MobileAccess antennas.

A mobile base station in the basement of the building feeds to modular remote cabinets (MRC) in wiring closets, which can be outfitted with a variety of wireless module types, such as cellular, paging, two-way radio, and now Wi-Fi APs from nearly any third-party vendor.

The MA-850 Wi-Fi module supports four APs; the ink was drying on a purchase order for nine of them last week at Lehman Brothers, which had already installed six MRCs for its cellular requirements, according to Coffey.

"The real driver was cellular," he emphasizes. "The new construction was killing BlackBerry coverage. Once the platform was in place, we found we could add [Wi-Fi] to it incrementally for very little money."