Examine the network exhibit.

A company has a guest implementation for wireless and wired access. Wireless access is implemented through a third-party vendor. The company is concerned about wired guest traffic traversing the same network as the employee traffic. The network administrator has established a GRE tunnel between AOS-CX switches where guests are connected to a routing switch in the DMZ.
Which feature should the administrator implement to ensure that the guest traffic is tunneled to the DMZ while the employee traffic is forwarded using OSPF?