Nortel, Intel and SprintNextel are betting the house on WiMax, but not everyone is a convert. Cisco, for one, seems wary.

Charles Giancarlo, Cisco's chief development officer, laid out some of Cisco's reasoning today at the company's annual analyst conference. Fixed WiMax won't isn't a "viable" technology in the developed world, he said, and mobile WiMax isn't yet proven. "Even if WiMax is viable in [the service provider] space, it's still a wireless vendor technology, and I don't think that's enough of a disruption for Cisco to enter the field," Giancarlo said. He hinted that Cisco is more interested in developing 4G technologies that will come after and possibly integrate elements of WiMax.

That's not to say Cisco hasn't put its toe in the water. The company's involved in a project to bring wireless access to the Bay Area, and WiMax is among the access technologies being considered there. Giancarlo says Cisco's also interested in WiMax backhaul and an IP interface for WiMax radios.

Back to the lead, it's interesting that in a networking technology where other major companies have invested heavily, Cisco has chosen to sit tight for now. WiMax advocates believe it's the future of wireless, and carriers like Clearwire and now SprintNextel clearly believe them. So why doesn't Cisco? For one, analysts have told me that AT&T and Verizon look like they may be likely to skip over WiMax on the way to 4G. That could be one reason holding Cisco back. Another reason is that WiMax promises the house, but only delivers a bit of it in today's version. Penetration, distance and bandwidth aren't up to where forecasters initially pegged them. Cisco may be playing it safe in WiMax, but it's not necessarily a bad idea.