Higher-speed Wi-Fi in the form of 802.11n access points and related hardware began rolling out in earnest in the first quarter of this year and the next-generation technology became an important topic at the Interop trade show this week.
But some IT managers at the conference are still sceptical of the local area wireless technology, saying they have not seen the purported transmission speeds and worry whether 802.11n gear will be truly supported by Power over Ethernet.
"Don't believe all of the hype" of 802.11n, said Jorge Mata, CIO at the Los Angeles Community College District, which has been testing 802.11n access points from Cisco Systems. "It's not anywhere near the increased speeds" that are advertised, Mata told an audience here discussing mobile technologies.
Mata said he has been testing about 10 802.11n access points. Currently, the college district, with nine campuses, has about 600 802.11b/g access points, all from HP ProCurve, he said.
In his testing, Mata said he found that the college district will need to have a dedicated network for 802.11n laptop and other devices. The reason is that any 802.11b/g-equipped laptop or device lowers the 802.11n speed to the slower technology.
"Plus, we've found power consumption goes up significantly" for devices running 802.11n, Mata said.
Alan Schostag, manager of information systems at Wessin Transport in Golden Valley, Minn., said his company has tested 802.11n and will not be adopting the technology until a final draft of the specification is approved by the IEEE. He said speeds and concerns over power are on his mind as well.
"We think 802.11n is not there yet," Schostag said. "It will be a while before we go all n. We think 802.11g is good for now."
Both Mata and Schostag said many users have become accustomed to using wired LAN connections with Gigabit Ethernet speeds, and the 802.11n testers have been disappointed by the 802.11n speeds.
A significant concern for both managers is whether the 802.11n access points on the market will function fully while drawing power from a Power over Ethernet connection. That kind of connection means the new access point doesn't require stringing a separate power line, but some 802.11n APs on the market don't provide the full advertised capabilities unless the POE is boosted by additional power. For instance, some 802.11n access points might have several radios, but not all will work with a PoE connection, they and analysts said.
Mata said his testing has shown that 802.11n access points are compromised when running over PoE connections. "They are lobotomised," he said.
A coming PoE-plus standard from the IEEE should improve PoE capabilities to support 802.11n, Mata and analysts said.
The PoE concern is a legitimate one that customers need to confront, analysts said. "That problem is going to come back and bite the vendors," said Mark Brandenburg, an analyst at Current Analysis. He said some vendors, which he did not name, are providing confusing information about PoE capabilities in their 802.11n gear. "It's lies, damn lies and even more lies," he added.
While some vendors are announcing 802.11n gear at Interop, the biggest push came in the first part of 2008, with announcements from Cisco, Aruba and Motorola, Brandenburg said. "It's a technology that vendors are moving in the market," he said, but the analysts said he hasn't yet done any comprehensive study of shipments or customer feedback.