Wireless Technology Meets the Real World
Bill Shadish

Sometimes there are obstacles...

Roger and Dodger struggle
The following dialog is imagined, or is it? ....

Roger: "Hey Dodger, if you have to move us to the new third floor next week; can we at least get temperature controls in the new office right away? It's freezing up there."

Dodger: "You know it takes 3-4 weeks after we schedule it before the contractor can run the wires for those controls. I'm sorry that this move is a rush -- but I can't change the schedule. We will have to get to this as soon as we can."

Roger: "Ok -- if you have to schedule things anyway, can we also get a separate printer wired so that our group can share it?"

Dodger: "Roger, you know how much it costs to run wires in the building. We will schedule setting up a separate shared printer when the funds are available for it, but we can't do it right now. Oh, and by the way, they aren't going to let you get away with hanging wires across the furniture again, so let's not go that way, alright?"

Roger: "Do you know if there is budget available for [sarcasim on] some pen and paper? [/sarcasim off]"

Click for larger picture

Wirelessly Equipped Building

The cost to wire equipment within a building is often among the highest individual line items involved in setting up new devices like computers and machine monitors. Fortunately, there are some new tools that can give Roger what he needs -- today.

Wireless Devices
Wireless technologies compared.
Wireless technologies compared.
Many types of commonly used devices, like the temperature sensor, now come in wireless versions. Other wireless devices include:

  • heating controls (http://www.toolbase.org/docs/ToolBaseTop/TechnologyInventory/3878_wirelessthermostats.html)
  • computers
  • printers
  • laptops
  • handheld PDAs
  • equipment monitors
  • sensors
  • alarms/fire detectors (http://www.worldelectronics.com/indust.htm)
  • data logging devices

In a complex model (see the figure) these devices can all be made to interact, so that computers can be used to monitor the monitors and gather information from throughout a building. The computers can then send messages to humans based on threshholds established for the monitors. In a simpler model, a computer can just wirelessly send a document to a printer for printing. In either case, the advantage of wireless-equipment is flexibility and mobility.

The figure shows a building near a river. Wireless devices are in place to monitor machinery, the environment and for computing purposes. All the information from these devices can be pulled into a central spot, for administrators to track what is going on, and react. If the water sensors need to move, wires are still not needed.

Not only is it very easy to install a new node of equipment but also the resulting device can communicate with other nearby wireless devices and, most importantly, be moved easily around a facility.

Benefits and Drawbacks
In addition to vastly reducing wiring and construction costs, there are other benefits to wireless technology. A wireless laptop taken to a different floor will immediately access the network and local printers, as well. Wireless networking cards cost about the same as other network cards.

Security is often cited as an issue in wireless networks because following the wire between two computers to see who can talk to whom does not identify all the users. Anyone with access (read that, the passwords) to a wireless network can access it. In the early days of wireless technology, people did not change the default passwords that came with equipment, allowing access to anyone walking around with a wireless PDA. These early breaches became folklore, and the concern remains.

Many levels of security can be applied to wireless equipment, from simply setting a password or adding layers of encryption to create custom hardware, just for you. The latter are not usually required. There are also some links containing a number of levels of security that can be configured for wireless hardware.

As with any new technology, the first wireless devices cost more than similar wired devices. Today a wireless Wi-Fi card for a computer costs $69, while a wired Wi-Fi card costs $49. Installing wiring shifts the cost benefit in favor of wireless devices -- especially in a building where the cost of placing anything in an established wall or ceiling is high.

Proprietary Hardware/Software

Depending upon the vendor, similar devices may be proprietary (made by only a single vendor or small group of vendors) or open standard (made by many vendors). For example, the Wi-Fi standard is in use in the vast majority of applications today.

Sometimes a proprietary solution is appropriate, even though it may be more difficult and more costly to add to a proprietary solution -- and it limits the choice of vendors. Similarly, the vendor may go out of business or decide to stop supporting the given item.

Open standard solutions also bring risks since the technology is still relatively new. Sometimes equipment from different vendors does not work together as expected, even if that equipment is supposed to support the same standard.

For example, there was a rush to market by hardware vendors to support the new higher speed 802.11g Wi-Fi standard before that standard was finalized. The devices were close to the standard, but didn't always work together properly -- especially if they came from different vendors.

TIP: Have a building survey conducted before deciding upon a wireless course. This will show how many wireless connection spots (access points) will be required -- and the ranges of the wireless devices given a building's location and construction. The audit typically takes a few hours, using signal strength meters, but it will reduce the number of access points and decrease the time and cost to implement a wireless solution.

Open Wireless Options
The two hottest wireless protocols are Wi-Fi and Bluetooth. Bluetooth is generally intended for connecting peripherals, like a computer to a printer or a PDA to a phone. Bluetooth acts as a short cable replacement. Bluetooth operates at about +/- 30-foot range, depending upon the hardware vendor and intervening walls, etc.

Wi-Fi is a related group of IEEE 802.11 standards, numbered 802.11a, 802.11b, 802.11g, with i, e, f and h coming (see chart). These variations focus largely on speed and exactly where in the radio-bandwidth the hardware operates. Wi-Fi works over greater distances and is meant (more as) a LAN wire replacement than Bluetooth. Wi-Fi can operate up to 150 feet from an access point, which connects the wireless devices into the wired LAN environment.

Energy-related peripherals, such as motors, engines, heat gauges and air monitors can be connected into the wireless network, so that they can be inspected from a remote connection or even a remote office. Machine monitor information can be wirelessly loaded into the LAN in the building in the figure, and inspected from a remote connection.

802.11b is the version that is being heavily promoted by the marketplace, with hardware available in Staples and Office Max, but 802.11g is something to consider, as g not only is backwards compatible with b, but the interference advantages are noticeable.

ROIs/Case Studies

  • ROI, COST estimates: http://macktez.com/recommendations/ 000826.html

  • Wireless LAN ROI: http://www.osws.com/pdf/Wireless_LAN_ROI.pdf

  • Wireless Local Area Networking: ROI /Cost-Benefit Study Executive: http://www.enterasys.com/products/wireless/WLANASTUDY-Ex.pdf

Wi-Fi Explained


Wireless Controls

Bill Shadish is a principal of Fundamental Objects, Inc (http://www.foaudits.com) where he works on client partnerships, custom energy software, and handheld technology. Shadish writes for a number of industry trade journals; including Home Energy Magazine and edits the FO handheld newsletter.

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