802.11 Wireless Specifications - What is Wireless G, Draft-N, A & B?

802.11 Wireless Specifications - What is Wireless G, Draft-N, A & B?
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Overview

When designing Wireless devices for networking, electronic engineers have to adhere to a set of established standards put in place by the IEEE society (Institute of Electrical and Electronics Engineers). These standards are a part of the set of 802 Ethernet standards, and are given the designation of 802.11. From there, further specifications are denoted by letters dealing with specific wireless technologies. Some common examples of these standards are: 802.11a, 802.11b, and 802.11g. There is also a less-known and less common “n” standard. We’ll consider the specifications and uses of these various wireless standards.

802.11a

While 802.11 (without a further letter designation) was technically the first official Wireless Ethernet standard, it wasn’t fully developed and the technology is now obsolete. The first commercial Wireless Ethernet specification to come about was 802.11a, but it was not the first one to hit the market. Although higher up on the letter designation ladder, and the first sub-specification to be commissioned, 802.11b beat it to the market.

802.11a operates on the not-widely used 5GHz wireless band and has a maximum net rate of 54 Mbps (Megabits per second). A lot of wireless devices, like cordless phones and Bluetooth, operate on the 2.4GHz wireless band. Additionally microwaves are known to interfere with 2.4GHz band devices as well. Operating on the 5GHz band offers a significant advantage because the chance of interference is much lower than for 2.4GHz devices. However, the high frequency also means that 5GHz band signals are more easily absorbed by walls and other objects, decreasing the overall effective range.

Since 802.11a came late to the party, and devices utilizing it were made available after 802.11b had already used up most of the market, it was not well received. Device function problems early in release didn’t do anything to help the matter, and ultimately 802.11a was largely forgotten, though it has yet to be entirely abandoned.

802.11b

For a long time, the 802.11b wireless standard was the only logical commercial option, both for business and home use. When compared to the A standard, B is incredibly unimpressive, and its success can only be attributed to its early and wide availability, and relatively low cost (both manufacturing and retail costs).

802.11b, unlike its older brother, uses the already flooded 2.4GHz band. It also only supports a maximum net speed of 11 Mbps. Realistically, does being on the 2.4GHz band really effect its performance? The answer to that question is a resounding yes. While some 802.11b users may go through life never experiencing problems, others (particularly those with cordless phones that operate on 2.4GHz) will experience nothing but problems. As a support specialist, I have received dozens of calls from wireless users losing their Internet connection every time they receive a phone call.

There are, of course, ways around this. In my own home I am using the 802.11g standard (discussed below, and which also operates on 2.4GHz band). Before installing my network I preemptively required my family members to do away with their 2.4GHz cordless phones, as these are also almost as widely available on 5GHz nowadays. Additionally, I placed my wireless router as far as possible from the microwave. With this configuration, I don’t experience any problems with signal interference.

802.11g

Following a little while after 802.11a and b, the “g” standard was seen as a refreshing upgrade and change from the norm. Taking a page out of big brother A’s book, the G standard is also capable of a maximum net speed of 54 Mbps. It was very widely and excitedly received because not only is it faster, but it is also backwards-compatible with the B standard, as it also operates on the 2.4GHz band. Wait, didn’t we just establish that the 2.4GHz band is wrought with troubles? Yes, we did. Fortunately in modern network implementations the issues with signal interference on that band can be minimized by taking a few precautions with other wireless devices like I did. Don’t forget, the 5GHz band has its own problem, namely low signal distance, so we’re essentially just left to picking out the better of two “evils.”

802.11n

The final wireless standard up for consideration today is the “fabled” wireless N standard. This is a funny one, as it has been in development for years, with its “official” ratification date continually being pushed back. Manufacturers majorly jumped the gun about two years ago, anticipating that the then-proposed standard would be ratified sooner rather than later, and theoretical wireless N devices are available for consumers to pick up.

The 802.11n standard is centered around MIMO (Multiple Input, Multiple Output) technology. In simple terms, N devices have multiple antennas arranged in a way to optimize signal strength and speed, and uses each simultaneously to interact with other wireless N devices. The theory is that by doing this that it will eventually achieve max net speeds of close to 600 Mbps. In its current unofficial release, N devices “can” achieve 300 Mbps (though the “effective speed” ends up being much lower).

Should you go ahead and buy N? It does offer faster speeds, though is not compatible with the other standards. You would have to make sure that all of your wireless devices supported it, or go out and buy new ones. The problem with buying N now, before the standard has been officially ratified, is that it could very well change and evolve before then. That would leave you with a bunch of useless (and more expensive) hardware if it were to happen, and you’d have to go out and buy the comparable “official” wireless N devices when they were released. That doesn’t sound like fun.