A. use BGP as the CE-PE routing protocol
B. use OSPF as the CE-PE routing protocol
C. use EIGRP as the CE-PE routing protocol
D. use the SP to redistribute routes as external routes for OSPF and EIGRP
E. use route redistribution at each location to ensure external routes are imported into the IGP

A. The NAS acts as a gateway for all Layer 3 traffic.
B. Only the MAC address is used to identify the client device.
C. User traffic remains on the same VLAN for the duration of the connection.
D. After authentication and posture assessment， client traffic no longer passes through the NAS.