Four-radio AP touts high-density Wi-Fi

Extricom's channel blanket wins friends

By Bryan Betts at the Wireless Event, Olympia • Get more from this author

Posted in Telecoms, 24th May 2007 09:25 GMT

Wireless Event Extricom has launched a quad-radio access point for its high-density wireless LAN systems.

These are combinations of ultra-thin APs with a wireless switch that runs all the APs as a single cell so they can be on the same channels without interfering.

Having four radios in each AP means you can run three non-overlapping Wi-Fi networks in the same area - the maximum possible on the 802.11b/g frequency - and still have a set of radios left over to scan for rogue APs or wireless intruders, said Extricom veep David Confalonieri.

Alternatively, as the radios are also 802.11a-capable, they could run a fourth network on that frequency.

Each of Extricom's switches can have up to 24 of the four-radio EXRP-40 APs hard-wired into it, and in effect it then runs them as radios. It refers to the technology as a channel blanket.

"It creates the impression of a single large cell," said Confalonieri. "The client associates with the switch, not with a specific AP."

He claimed this can make the network more resilient to interference than standard APs, because the switch can connect to the same client through several radios, not just the ones closest to the source of interference.

By coincidence, ZyXEL is also launching its ultra-thin AP/switch combo into the UK market on the stand next door at the same time - and ZyXEL's is based on Extricom technology.

Product manager James Walker makes the point that most wireless switch systems operate their thin APs on different channels, moving them from channel to channel to achieve best coverage. By comparison, ZyXEL's (and therefore Extricom's) are all on the same channel, which reduces the need for clients to reconnect when moving from one AP to another. ®

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