802.11n
An IEEE 802.11 wireless network standard that increases transmission speeds to 100 Mbps and beyond. The final standard is expected in 2009. Because 802.11n works in both the 2.4 GHz and 5 GHz frequency bands, it is compatible with legacy 11a and 11b/g users (see dual-band router).
Multiple Antennas (MIMO)
The key to the 802.11n standard is the use of multiple antennas. "Multiple input/multiple output" enables two data streams to be sent simultaneously over longer distances. See MIMO.
Pre-N and Draft-N
In 2004, Belkin was the first vendor to introduce a "Preliminary-802.11n" access point and laptop card using its own ingenuity and the latest drafts from the IEEE. Both access point and laptop cards had to be from Belkin. Other vendors followed with their own proprietary "Pre-N" equipment.
In 2007, the Wi-Fi Alliance launched its certification system to validate 802.11n equipment using Draft 2.0 of the specification so that different vendors' equipment could work together. Referred to as the "Draft-N" standard, firmware upgrades may be required to bring Draft-N devices up-to-date when the final standard is ratified. See MIMO and 802.11.
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| Pre-N Equipment |
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| Introduced in 2004, this Belkin wireless router uses two transmitters and three receivers to deliver a maximum speed of 108 Mbps. (Image courtesy of Belkin Corporation, www.belkin.com) |