February 01, 2006
| by Gordon van Zuiden
These new products are often referred to as “pre-N” devices. This is because the 802.11n standard is not expected to be ratified until later this year. But once again, manufacturers are jumping the gun with products they think will be compatible with 802.11n. And that’s the danger for eager adopters of this technology: Without a full standard to go by, there is no guarantee that those products will be compatible.
So, if you purchased a Belkin 802.11 pre-N wireless card for your laptop, it will work with your wireless Belkin 802.11 pre-N access point—but possibly not with a pre-N access point from another company.
The good news is that these products are generally backward compatible, meaning that if they cannot connect at the faster 802.11 pre-N speeds, they will transmit at the slower 802.11g or 802.11b speeds. (See “Wireless Soup” for more information on the other standards.)
In this increasingly confusing alphabet soup of standards (b, g, a and now n), it’s comforting to know that your computer can still connect to the Internet over a wireless network, even if you may not know the standard used by your laptop’s wireless card. You just may find that the connection is not at the optimal speed, and your wireless range is more limited.
The prospect that the new “n” standard will be able to stream video data over a greater range opens up the possibility of watching high-quality TV transmissions streamed from a cable tuner to a laptop in the backyard. The new Slingbox and Sony Location Free products provide this capability today, based on the more limiting wireless range and speed of the 802.11g standard. However, once these products adopt the 802.11n standard, we should be able to enjoy our TV channels streamed in higher resolution to any wireless device.
That device would most likely be a laptop, but it could be one of the many new handheld video products that have recently been introduced, such as the Apple video iPod or the Sony PlayStation Portable. This untethered access will give us greater opportunities to enjoy entertainment wherever we are.
More on N
The 802.11 “pre-N” wireless products are based on a new wireless technology called MIMO. The term “MIMO” (multiple input multiple output) refers to the ability of 802.11n to coordinate multiple radio signals at once. One industry group, led by Airgo, a pioneer in MIMO technology, is developing an 802.11n proposal that utilizes 2 x 2 MIMO—meaning two transmitters and two receivers in each device—to get speeds of up to 140 Mbps. Optional transmit and receive components added to this could boost data rates up to 540 Mbps.
There have already been several flavors of the 802.11 wireless networking standard. Here they are, in order of their releases:
- 802.11b The first residential release was in late 1999 and provided data transfer speeds up to 11 Mbps with an in-home range of about 50 to 75 feet.
- 802.11a This standard became available around 2001 and gave us speeds up to 54 Mbps but reduced the range in half.
- 802.11g To solve the range limitation issue, 802.11g was introduced a few years ago to give us a speed of 54 Mbps with a range of 50 to 75 feet inside the home.
- 802.11n This emerging standard promises speeds beyond 200 Mbps and an indoor range close to 200 feet.
Gordon van Zuiden is the founder and president of cyberManor: www.cybermanor.com.