.FLYINGHEAD WIRELESS INFRASTRUCTURE
.TITLE Wireless standards for mobile ad-hoc networks
.AUTHOR Humayun Bakht
.SUMMARY In computing terms, a network is a collection of two or more machines that share information with each other. These days, wireless networks offer more services and benefits than ever before. And the proof is in the pudding as more and more companies and home users take advantage of this technology. In his continuing quest to educate our readers all there is to know about wireless technology, Contributing Editor Humayun Bakht introduces you to the most common wireless standards.
.DEPT
Wireless networks tend to offer numerous benefits, including wider coverage, cost reduction and data transmission at high speeds. In this article, we will investigate different available wireless standards as defined by the Institute of Electrical and Electronics Engineers (IEEE).
Developed back in 1997, IEEE 802.11 was the first wireless local area communication standard. Although IEEE 802.11 is very slow and can support data transmission up to 2 Mbps, its development opens a new chapter in the field of wireless communication. Nearly all of the existing or the newly developed wireless standards are either based on or are an extension of IEEE 802.11.
There are three formats using the IEEE 802.11 standard. They are 802.11a, 802.11b, and 802.11g. These are the most commonly used standards today. You’ll see them in home networks, in laptops, coffee shops, airports, etc. Let’s find out how they compare.
IEEE 802.11b is a Wireless Local Area Network (WLAN) standard that was developed in July 1999 and can offer a maximum bandwidth of 11 Mbps. The main benefit of IEEE 802.11b is its cost. This is mostly because network equipment for 802.11b costs less than some of the other wireless standards. IEEE 802.11b uses a 2.4 GHz frequency range. The 2.4GHz frequency is unregulated, meaning that there are many devices that could use this frequency range, such as cordless phones, microwaves, and even your laptop computer. As a matter of fact, all the standards which operate with 2.4 GHz frequency range are subject to the interference of other wireless services utilizing the same frequency range. This interference causes not only distraction in effective data transmission but also reduces the over all efficiency of various wireless equipment. However, in the case of IEEE 802.11b, this interference can easily be avoided by the installation of some extra equipment.
The 802.11a standard followed two years later, in 2001. It supports a maximum bandwidth of 54Mbps, which is one of the main benefits of using IEEE 802.11a. It’s much faster than using 802.11b. Even though 802.11a is much faster than 802.11b, why isn’t more widely used? 802.11a does have a couple of drawbacks. The first is the extra cost which is required to manage hardware equipment. IEEE 802.11a also uses 5GHz or above frequency for radio transmission. Moreover, 802.11a has been ratified to support interoperability among various vendors.
IEEE 802.11g is another well-known wireless standard in the series of IEEE 802.11. It was last modified in 2003 and is regarded as one of the latest addition in the series of wireless standards. It extends the performance of 802.11b standard in many ways and can support data transmission up to 54Mbs. In reality, 802.11g attempts to combine the best of both 802.11a and 802.11b. IEEE 802.11g uses the standard frequency range of 2.4 GHz and it offers both higher throughput and backward compatibility with 802.11b access points. These access points operate in the same frequency but have a throughput of 54Mbps which is one the main features of IEEE802.11g.
The latest common 802.11 standard is 802.11n, which is faster and offers longer distance communication. While there are many devices available using 802.11n, the standard has yet to be formally published.
.BEGIN_KEEP
WLANs have a broad range of standards, some of which are well established and interoperable, while others are still underdevelopment. No matter what the present situation of these standards may be, there are still some issues like security and interoperability that raise questions about the overall adaptability of these standards. The way I see it, there’s definitely a need to work on these standards, which could provide opportunity for developers and consumers by turning the wireless market into a more diverse environment than ever.
.BIO
.END_KEEP
