Available Control Plane Subinterfaces

BDE.

Cisco IOS Control Plane Protection (CPP) is a feature that provides mechanisms to protect the control plane of a Cisco device from various types of attacks. The control plane is the part of the router or switch that manages and controls traffic forwarding, routing protocols, and management functions.

The control plane is vulnerable to various types of attacks that can disrupt network operations or compromise the security of the device. To protect the control plane, CPP provides several subinterfaces that can be used to apply different security policies.

The three control plane subinterfaces available when implementing Cisco IOS Control Plane Protection are:

A. CPU: This subinterface controls traffic destined for the router's CPU, which is responsible for processing control plane traffic. The CPU subinterface can be used to apply policies such as rate limiting, access control lists (ACLs), and quality of service (QoS) policies to limit the amount of traffic that reaches the CPU.

B. Host: This subinterface controls traffic destined for the router's IP address, which is used for management purposes. The host subinterface can be used to apply policies such as ACLs and QoS policies to limit the amount of traffic that reaches the router's management IP address.

E. CEF-exception: This subinterface controls traffic that triggers a CEF ( Cisco Express Forwarding) exception, which occurs when the router encounters a packet that cannot be processed by CEF. The CEF-exception subinterface can be used to apply policies such as rate limiting and ACLs to limit the amount of traffic that triggers CEF exceptions.

The other options are:

C. fast-cache: This subinterface controls traffic destined for the router's fast cache memory, which is used for packet forwarding. Fast-cache protection is not a supported subinterface for CPP.

D. transit: This subinterface controls transit traffic passing through the router. Transit protection is not a supported subinterface for CPP.

F. management: This option is redundant and similar to option B. The host subinterface controls traffic destined for the router's management IP address, which is used for management purposes.