"You don't get value from NAC. You get value from systems that interoperate with NAC," Hansen said.

Thus far, however, Cisco's integration with other products -- especially those of competitors in the networking infrastructure space, is almost nonexistent, while the cost of implementing the NAC framework end to end is prohibitive, Hansen said.

Cisco's idea of enforcing policy at the infrastructure level may be superior to other solutions, such as Microsoft's NAP. However, NAP could end up winning out at companies by virtue of being less expensive and easier to deploy, Hansen said.

"Cisco's great at IOS and turning ports on an off, but they're late to the security game, and Microsoft may end up dominating it," he said.

Gleichauf acknowledged that customers want choice and that moving to an open-standards model could stimulate that, but he said that Cisco will have to work towards it incrementally.