Before your license expires, you have to renew the license, if you don't need advance assurance then you can just buy essentials, but you will still need DNA license for access to TAC support, OS support and OS updates. If you decide not to renew the DNA license, it is recommended that the you purchases Smart Net Total Care (SNTC) for both the AP and controller. With SNTC, the customer will receive hardware technical support, including OS support, software updates, and Next Business Day Return Materials Authorization (RMA).
-hope this helps-
