The Wild World of Wireless Standards
Many IT professionals who have casually expressed an interest in breaking into wireless computing may have been discouraged when they started to study the far-reaching and somewhat Byzantine set of standards the industry operates by. Well, we’re here to help. Inasmuch as it’s possible, we’ll try to break down and simplify some of these standards for you, so that you can get down to the nitty-gritty of wireless networking and avoid getting too bogged down by details.
Why So Many?
The main reason there are so many standards out around wireless is that there are several wireless organizations out there, which are all pulling the field toward their particular technology or idea of what the industry should be doing. Additionally, different protocols address varying aspects of wireless: Some deal with clear communication, others with security and so forth.
One of the best-known wireless standards associations is the Institute of Electrical and Electronic Engineers (IEEE), which encompasses more than 365,000 members in approximately 150 companies. (Nearly 40 percent of its membership is outside the United States.) While it was not established—nor is it strictly devoted—to promote wireless criteria, it does develop and advocate the widely accepted 802.11 set of wireless standards.
The Bluetooth Special Interest Group (SIG) is another example. This organization is dedicated to the creation and promotion of the Bluetooth wireless specification, which explains how mobile devices like smartphones, laptops and PDAs can be linked to any other device with transceiver chips via short-range, low-cost radio solutions.
802.11: Keeping It in the Family
IEEE’s suite of wireless LAN standards includes some that have already been adopted and are used extensively in the field, whereas others—at the time of this writing—are either still highly theoretical and under development by the organization’s task teams, or apply to very unique circumstances. We’ll focus more on the former. Here they are:
- 802.11: The granddaddy of them all, this regulation more or less lays the framework for all the ones that follow. 802.11 pertains to transmissions that involve 1 or 2 megabytes per second (Mbps) in the 2.4 GHz band using either frequency-hopping spread spectrum (FHSS) or direct sequence spread spectrum (DSSS).
- 802.11a: A kind of addendum to 802.11, this standard relates to wireless ATM systems and is used in access hubs. It provides up to 54 Mbps in the 5 GHz band, although transmissions seldom exceed 24 Mbps. Also, instead of FHSS or DSSS, 802.11a uses an orthogonal frequency division multiplexing encoding scheme.
- 802.11b: Simply put, this one’s Wi-Fi. 802.11b employs the complementary code keying (CCK) modulation technique, which permits higher data speeds and is less vulnerable to multipath-propagation interference. Its frequency range is between 2.4 GHz and 2.4835 GHz.
- 802.11e: This standard, which was actually finalized by IEEE only a few months ago, spans both home and enterprise wireless operating environments. It is aimed to enhance 802.11a and 802.11b specifications with quality-of-service (QoS) features and multimedia support guidelines.
- 802.11g: Another recently approved standard, this one covers wireless transmissions at up to 54 megabits per second (Mbps) over relatively small areas. 802.11g is compatible with 802.11b, as both of these operate in the 2.4 GHz range.
- 802.11i: This regulation deals with a major concern of many users of wireless technologies: security. 802.11i brings the Advanced Encryption Standard (AES) security protocol to 802.11. It also includes the Temporal Key Integrity Protocol (TKIP), a set of algorithms that enhances encryption capability.
Outside of the immediate 802.11 family—cousins, if you will—are 802.15, a specification that involves wireless personal area networks (wPANs) and is compatible with Bluetooth standards, and 802.16, which covers broadband wireless communications principles for metropolitan area networks (MANs). The latter even has its own advocacy group. You may have heard of it: The WiMAX coalition counts tech heavy-hitters like Intel and Nokia among its members.
What in the World Is Bluetooth?
Bluetooth takes its name from Harald Bluetooth, a relatively obscure 10th century Viking ruler in present-day Denmark who ostensibly facilitated greater communication between people in his time. As a concept in wireless, it’s hard to pin down. Bluetooth is definitely a technology, but it’s also a corporate community that includes Nokia, Motorola, Ericsson and many other companies.
What they all have in common is that they follow specifications developed by the organization in using Bluetooth technology in their products. The latest of these is Version 1.2, the fourth generation in Bluetooth standards. All of these regulations are in a checklist format that covers criteria such as protocol and profile provisions and test specifications. These are available for download on the Bluetooth SIG Web site (http://www.bluetooth.org).
WAP (Wireless Application Protocol):
Developed in 1997 by Ericsson, Motorola, Nokia and Unwired Planet (now Phone.com), the WAP specification concerns the ways in which wireless devices can access the Web and operate in corporate intranets. This standard is designed to help administrators, manufacturers and providers overcome obstacles in differentiating themselves in the market and offering fast and flexible service.
WAP encompasses four layers: Wireless Application Environment (WAE), Wireless Session Layer (WSL), Wireless Transport Layer Security (WTLS) and Wireless Transport Layer (WTP). The Wireless Markup Language (WML), an open language that can be accessed and used without any royalty payments, makes WAP possible by allowing users to access text portions of Web sites through cell phones and PDAs.
Are We Finished Yet?
We’ve only scratched the surface on the existing wireless standards. I’d like to say this is an exhaustive overview of regulations, but there are many, many others out there. Until the entire industry comes under one set of standards (don’t hold your breath), you’ll have to research which wireless products and services your employers or customers use, and adjust your comprehension of particular specifications accordingly.
–Brian Summerfield, firstname.lastname@example.org