The 802.11a standard provides bandwidth of up to 54mbps on a wireless local area network. About 150 users currently have access to the college's wireless Lan, and it plans to deploy a further 100 Dell Latitude C8450 notebook PCs, equipped with 802.11a network cards in July.
Chris Zisimides, network manager at Plymouth College, said, "Our aim is to provide as many lecturers as possible with laptop PCs. We trialled 802.11b hardware but found it was not suitable for running videos or presentations." He also wanted enough network bandwidth headroom to support up to 600 users at a later date.
Zisimides selected Intel's 802.11a access points and deployed power-over-Lan technology from PowerDsine to avoid having to install electrical cable.
"Installing power cables would have been prohibitively expensive," he said. It also would have taken longer than the eight-weeks Zisimides had to install the wireless network.
Power-over-Lan is designed to overcome this issue by using the network cable to provide electrical power to devices such as wireless access points.
The college's existing network infrastructure was based on Cisco equipment, but Zisimides said he could not justify the cost of upgrading his network switches to support power-over-Lan from Cisco. Instead he bought a power-over-Lan module from PowerDsine called Midspan, which fits between the Cisco switch and the wireless access point.
To tackle security, the college has installed a wireless gateway server called Bluesocket. The Bluesocket hardware acts as a wireless security gateway to authenticate any user connecting to the wireless Lan. Bluesocket offers network bandwidth management so users are prevented from hogging the network's bandwidth. It also provides IT administrators with policy-based management to control access into the college network.
How does power over Lan work?
Power-over Lan technology routes DC electrical power over Ethernet cabling, avoiding the need for separate electricity supplies. Its main benefit is that it offers users cheaper, more flexible deployment of devices such as wireless Lan and voice-over-IP equipment.
It decreases installation costs for devices such as voice over IP phones, wireless Lan access points or webcams and, because it controls the power supply centrally, it allows functions such as hard resets to be carried out remotely.
Power over Lan allows 48V DC to be transmitted over spare data pairs in 10/100 Ethernet cabling, sufficient for devices up to 15.4W.
This was first published in June 2003