As it descends on to the enterprise, telecom designers and technicians can and should play a major role.
April 1, 2004
Prices for low-end wireless routers and access points just keep spiralling downward. For example, I was able to get a wireless access point for $40, plugged it into my router and was up and running in no time.
Four-port routers with wireless access can be had for under $50. Recently, I was at a wireless information seminar where every attendee was given a wireless router just for being there.
So what does this mean for telecom designers and technicians? Since these are all plug-and-play devices, designed so that a user can hook them up quickly in order to take advantage of wireless access, it can be argued not much.
They don’t offer sophisticated security options or antennas that can be tuned for specific coverage patterns and other features. Many of them lack on/off switches (the best security when you don’t need to be connected) and the A/C adapter type power supplies can be a nuisance at times.
In short, they’re not exactly the type of device you would want to put into an enterprise network.
Then again, once an employee is able to work from anywhere they quickly see the benefits of mobile wireless computing.
That demand is pushing the market to develop equipment that meets the needs of the enterprise user and it’s where the where the skills of telecom designers and technicians come into play.
They know and understand the environment that the wireless network needs to operate in, where to place the access points or antennas for the best coverage, while not spilling out RF signals into an unintended area, how to power the devices (direct, or PoE) and how to get cabling to a particular device.
Integration into the network is also critical. While the SOHO user generally connects to a cable modem or DSL, the enterprise user will likely connect to an existing LAN.
As a result, issues of virtual LANs, switching, addressing, management and maintenance have to be considered. Security in wireless network access takes on a whole new level, which requires detailed knowledge and expertise.
Other wireless applications such as voice, video and other data devices (bar code readers, POS devices, etc.) may also have to be incorporated into the design.
An 801.11 primer
The best place to begin to understand what wireless is all about is to review the standards.
The covering standard is the IEEE 802.11 and includes:
IEEE 802.11 Wireless LANs: This specification is for an RF connection between a wireless client and a base station/access point, as well as peer-to-peer wireless users. The 802.11 standards are similar in structure to the 802.3 standards for Ethernet 802.11 and have a number of subsets that are driving the LAN marketplace with a huge number of different base stations, antennas, device cards and adapters.
IEEE 802.11a describes wireless LAN device operation in the 5 GHz frequency range. Data rates of 6, 9, 12, 18, 24, 36, 48. and 54 Mbps are achievable. 802.11a devices are incompatible with other devices complying with the other 802.11 standards. This is because systems using 5 GHz frequencies will not communicate with system’s using 2.4 GHz frequencies;
IEEE 802.11b: Referred to as “High-Rate” and Wi-Fi, it specifies direct sequencing (DSSS) systems that operate at 1, 2, 5.5 and 11 MHz per second. 802.11b-compliant devices are also backward compatible and support both 2 and 1 MHz per second data rates.
Backward compatibility is important because it allows a wireless LAN to be upgraded without the cost of replacing hardware. This makes 802.11b compliant hardware extremely popular;
IEEE 802.llg: This provides the same maximum speed of 802.11a, coupled with backwards compatibility for 802.11b devices.
Once you know the standards, understanding design, installation and implementation is your next step. BICSI, which can help make that step an easy one, has encompassed wireless in a big way.
It has always had a section on wireless and RF in the design manuals and now it is ready to release a manual dedicated to wireless design. There are also courses available and, more importantly, there will be a certificate program to recognize expertise in the wireless marketplace.
Two versions of the certificate will soon be available — one that extends the RCDD designation and another that is a standalone certificate.
Roman Dabrowski, RCDD, is the Canadian Director of BICSI and a sales consultant with Bell Nexxia. He can be reached via e-mail at email@example.com.