That vision concerned Steve Hannah of the Trusted Computing Group, which promotes open standards for network access control that allow third party software to speak a common language when making access control decisions.

Releasing the NAC client as an open source application was a fine gesture, but it has little value to the community at large until Cisco agreed to submit its NAC protocols as open standards, he said.

"Ultimately, Cisco retains control, and you end up with Cisco as the center of the universe. So customers are stuck buying Cisco gear and looking for things that plug into Cisco gear, but they don't really have a choice of different vendors," said Hannah, who is a distinguished engineer at Cisco competitor Juniper Networks.

TCG is happy to talk with Cisco about moving NAC protocols to open standards, perhaps blending NAC technologies from Cisco and TCG to give software vendors and enterprises the most choice, he said.

In the end, submitting CTA as an open source application may just be a politically correct way of throwing in the towel on an application that had become irrelevant, said Oltsik.