Hi,
Thank you for posting in Symantec community.
I believe you no longer can purchase SNAC licenses now. Even SEP 11 is reaching EOL soon.
I recommend to migrate to SEP 12.1 latest version.
Host Integrity, a feature of Symantec Network Access Control, will be integrated into a future release of Symantec Endpoint Protection (SEP). Customers who have SEP entitlement can continue to use the Host Integrity feature. Those who require advanced network access control capabilities should speak to their current network device providers whose products may have already incorporated this technology.
Host Inegrity feature will be added into SEP. Advise the customers to use SEP only.