Which of the following is a QoS feature that can apply policies to individual controlplane subinterfaces? (Select the best answer.)
Control Plane Protection (CPPr) is a Quality of Service (QoS) feature that can apply policies to individual controlplane subinterfaces. Control plane traffic is traffic that is destined to the router and that requires CPU intervention for processing. Because control plane traffic requires CPU intervention, it is possible to overload the CPU with a surge of traffic. When the CPU is overloaded, the router might be unable to update its routing information and transit traffic can be affected. With CPPr, traffic from the aggregate control plane interface is classified into one of three control plane subinterfaces: host, transit, or Cisco Express Forwarding (CEF) exception. QoS policies can then be applied to each of the subinterfaces individually.
Like CPPr, Control Plane Policing (CoPP) is a QoS feature that can be used to limit the type and amount of traffic that reaches the control plane. However, CoPP policies are applied to the aggregate control plane interface and not to the individual control plane subinterfaces.
Management Plane Protection (MPP) is a security feature that can specify one or more interfaces as management interfaces, not a QoS feature that can apply policies to individual control plane subinterfaces. A management interface is an interface that is permitted to receive management traffic, which is traffic from a specific set of network protocols that is destined for the router. Once MPP is enabled, only specified types of management traffic are permitted on their respective management interfaces. MPP simplifies the configuration of management plane security policies because it reduces the number of configuration steps required to restrict management access to the router. Without MPP, you would need to create the appropriate access control lists (ACLs) and apply them in the inbound direction to every interface on the router if you wanted to limit access to one or more interfaces and management protocols.
Unicast Reverse Path Forwarding (uRPF) is an antispoofing mechanism that verifies that the source address of a packet is reachable from the interface on which the packet was received, not a QoS feature that can apply policies to individual controlplane subinterfaces. If uRPF is used in conjunction with an ACL, it can cause packets to become packetswitched. Packet switching requires CPU intervention and can create a burden on the control plane.