Meru announces four-band 802.11n Wi-Fi

Wireless LAN maker Meru has announced a four-radio IEEE 802.11n wireless access point designed to provide reliable office Wi-Fi, as well as a virtual-reality tool which will determine wireless signal strength throughout a building.

The AP440 has four radios that can each support the full draft IEEE 802.11n standard, in either the 2.4GHz or the 5GHz band. Meru's "channel blanket" architecture means that all four can be in use at once, though likely set-ups will probably use one radio for monitoring, intrusion detection, and protection from rogue access points.

Four radios at once, each with a "symbol rate" of 300Mbit/s would give the AP a total capacity of 1.2Gbit/s but, as with all Wi-Fi systems, useful throughput will be substantially lower.

"By 2010, we predict that 79 percent of new connections will be wireless," said Rachna Ahlawat, Meru's vice president of marketing. "Security is no longer the number one concern - it is now reliability, followed by capacity, scalability, security and price."

Although the access point will be announced at next week's Interop conference in Las Vegas, it won't be available until the third quarter of this year. This could be useful in that it may allow electrical power to catch up with it. The current standard for power over Ethernet, IEEE 802.3af, will not deliver enough electrical power to run four Wi-Fi radios, but the next specification, 802.3at, should start to be available in products by then, said Vaduvur Bharghavan, Meru Networks chief technology officer.

The four radios should operate omni-directionally and without interfering with each other, said Bharghavan. With four channels, it will be easier to avoid unexpected interference, such as that from microwave ovens, said Bharghavan. "The best thing is to have a parallel channel available in the same band," he explained, saying traffic can move across right away, whereas in a channel-planning WLAN, such as those of Aruba, Trapeze and Cisco, moving an AP from one channel to another would mean dropping all the clients, and then changing the channel - and then changing channels on neighbouring APs. "If clients need to change channels, we are optimised to do that. It's not been done before."

The access point also includes a USB port, so the user can plug in a Wi-Fi monitoring device, on a few access points, such as the Metageek Wi-Spy spectrum analyzer, which improves on plain Wi-Fi monitoring by spotting other sources of interference such as microwave ovens and Bluetooth. "We have software on the AP that interfaces and pulls spectrum analysis off the Wi-Spy" said Bhargavan. "As spectrum analyzers get more sophisticated, it won't require a hardware upgrade to the AP - you can just plug in a different analyzer."

Meru is also announcing a virtual-reality visualisation tool which can display three-dimensional "heat-maps" of Wi-Fi coverage in a building. It relates access points on different floors, so should give a better indication of coverage, and allows the network manager to move through the building checking on likely coverage from his or her desk. This is an additional extra to Meru's existing management software, and costs $9,995.