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Monday, January 07, 2013

A Guide to 802.11n Wireless Home Networking

By John R. Delaney

See how the new 802.11n technology will benefit you. Plus, we review nine 802.11n routers.

After years of being labeled a draft specification, the 802.11n wireless networking standard is on the verge of finally becoming an official wireless specification. Members of the IEEE (Institute of Electrical and Electronics Engineers) aren't expected to vote on the final draft until July 2009, but the spec will, for all intents and purposes, become final sometime this fall. This means that all provisions and amendments to the draft will have been resolved, compatibility issues will have been dealt with, and any minor changes to the finished spec can be addressed via firmware updates rather than at the silicon and hardware levels.
"Draft" 802.11n wireless products have been available for more than a year now, of course, and although the latest Draft 2.0 products are generally faster and more stable, they're still out there without the IEEE's stamp of approval. The Wi-Fi Alliance is also awaiting final IEEE ratification before they drop the "draft" label from a long list of Draft 802.11n products. As a result, many consumers have been waiting for the standard to become official before taking the plunge and investing in the technology, which features faster transmission speeds and a wider range of operation than previous standards, such as the popular 802.11b and 802.11g protocols.
But current Draft N products are only a firmware upgrade away from being official 802.11n devices, which means you don't really have to wait to take advantage of the spec's technical improvements. Keep reading to find out more about the evolution of home networking technology. Then take a look at our wireless home networking buyers guide for advice on building your own network, as well as nine 802.11n router reviews to see what's currently on the market.


Back in 1999, the 802.11a wireless standard was released, boasting fast data rates of 54 megabits per second (Mbps). This protocol runs on the 5GHz frequency band, but its range is significantly reduced by infrastructure (walls, beams, flooring, etc.). That year also saw the release of the 802.11b standard, which operates on the 2.4GHz band and has a maximum data rate of 11Mbps. Theoretically, 802.11b is capable of indoor transmission ranges of up to 150 feet and is not as impeded by infrastructure as 802.11a transmissions, which is why it quickly became the protocol of choice for home and office use, despite its slower speed. Some manufacturers still use this standard in their handheld gaming devices, and many consumers employ 802.11b technology for their wireless home networking needs, but the slower rate makes it difficult to move large chunks of data across the network. Plus, 802.11b devices are susceptible to interference from household devices such as microwave ovens and cordless phones, many of which operate on the same 2.4GHz frequency.
In 2003, the 802.11g standard was approved. It also operates on the 2.4GHz band and has the same range capabilities as 802.11b, but it has a maximum transmission rate of 54Mbps, nearly five times faster than 802.11b. Plus, it offered increased security features that did not exist in 802.11b devices. Naturally, this standard became the popular choice among users who required the higher bandwidth, but early products were expensive. At the same time, 802.11b products saw a dramatic drop in price, providing budget-conscious consumers an opportunity to join the wireless revolution without spending a fortune.
The earliest Draft 802.11n products, introduced in 2006, featured dual-band capabilities (2.4GHz and 5GHz), data rates up to 300Mbps, and almost double the transmission range of 802.11b/g devices. This specification also takes advantage of multiple input, multiple output (MIMO) multiplexing, which uses multiple antennas to receive wireless transmissions faster than ever before, and at a longer range. The standard also gets a boost by way of channel bonding, wherein the router and Wi-Fi clients use two 20MHz radio channels to achieve a channel width of 40MHz, which helps speed up transmissions. If you already use one of the previous standards for your wireless network, don't worry: 802.11n is backward compatible with 802.11a/b/g products.


What does the ratification of 802.11n mean for consumers? For starters, there will almost certainly be more vendors jumping into the game, meaning more products to choose from, which usually leads to lower prices. As the standard has passed through its various draft stages, drivers and source code have been tweaked and perfected, so it's likely that we'll see better-performing products manufactured using the official specification. We'll also see a higher degree of interoperability between devices, with less signal interference than we saw in the earlier products.
For home users, the added bandwidth makes it possible to stream music and video, run network-attached storage (NAS) devices, and play online games without lag time. The new protocol is also ideally suited for communications applications such as Voice over Internet Protocol (VoIP) and video conferencing, both of which require lots of bandwidth to work effectively. Eventually, 802.11b will go away as demand and support for these products begin to dwindle. That means 802.11g products will likely become the low-end, low-budget wireless protocol—at least until the next standard comes along.

BEYOND 802.11N

So what's next on the wireless horizon? A new standard, known as Very High Throughput (VHT), will feature data rates of between 4Gbps and 7Gbps, nearly five times the rate of 802.11n, and will operate on the 60GHz frequency band. As such, the new standard will likely have limited range and will be best suited to peer-to-peer applications such as streaming video from one device to another or moving very large chunks of data in a matter of seconds.