350-401 Security Practice Question
A network administrator is deploying Control Plane Policing (CoPP) on a Cisco IOS XE router that runs BGP, OSPF, and SSH management. The administrator wants to protect the route processor from excessive control-plane traffic while still allowing legitimate routing protocol and management traffic. The administrator creates a class map that matches BGP, OSPF, and SSH traffic and applies a police action with a committed information rate. Which additional configuration element is required to complete the CoPP implementation?
⚠ Common exam trap
The trap here is assuming that applying a policy map to physical interfaces protects the control plane, when CoPP specifically requires attachment under control-plane configuration mode.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Apply the policy map to the control plane using the service-policy input command under control-plane configuration mode.
CoPP is implemented by defining class maps to identify control-plane traffic, a policy map to apply actions such as police, and then attaching the policy map to the control plane with service-policy input under control-plane configuration mode. Without that attachment, the policy is never applied to control-plane traffic, so the route processor remains vulnerable to excessive protocol or management packets.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Configure a route map that matches the control-plane protocols and reference it in the policy map.
Why it's wrong here
Route maps are used for routing policy decisions, not for classifying control-plane traffic for CoPP. CoPP classification uses class maps with match statements such as match access-group or match protocol, so a route map is not the required element.
- ✗
Apply the policy map to all physical interfaces using the service-policy input command under interface configuration mode.
Why it's wrong here
Applying the policy map to physical interfaces affects transit data-plane traffic, not traffic destined to the route processor. CoPP specifically targets control-plane traffic, so interface-level application would not protect the CPU from routing protocol or management floods.
- ✓
Apply the policy map to the control plane using the service-policy input command under control-plane configuration mode.
Why this is correct
CoPP requires a policy map to be attached to the control plane with service-policy input under control-plane configuration mode. Without this attachment, the class maps and policy map exist but are not enforced on control-plane traffic, leaving the route processor unprotected.
- ✗
Enable NetFlow on the router to export control-plane traffic statistics to a collector.
Why it's wrong here
NetFlow provides traffic visibility and accounting but does not enforce policing or protect the control plane. While it can help monitor traffic patterns, it is not a required configuration element for CoPP and does not rate-limit control-plane packets.
Visual reference
Quick reference
Routing Protocol Comparison
| Protocol | Metric | Max Hops | Algorithm | Type |
|---|---|---|---|---|
| RIP v2 | Hop count | 15 | Bellman-Ford | Distance vector |
| OSPF | Cost (bandwidth) | Unlimited | Dijkstra (SPF) | Link state |
| EIGRP | Composite metric | Unlimited | DUAL | Hybrid |
| IS-IS | Cost | Unlimited | Dijkstra | Link state |
| BGP | Policy / attributes | Unlimited | Path vector | Path vector |
RIP's 15-hop limit makes it unsuitable for large networks. OSPF and EIGRP dominate modern enterprise deployments.
Go deeper
Related to this question
Learn chapter
QoS and Network Performance Management
Key term
Control Plane Policing
Control Plane Policing is a Cisco security feature that protects a router or switch by rate-limiting the traffic that the device's processor must handle, preventing it from being overwhelmed.
Key term
Control Plane Protection
Control Plane Protection (CoPP) is a security feature on Cisco routers and switches that filters traffic destined to the device's control plane to prevent attacks and ensure stability.
About these practice questions
One of 1,923 original 350-401 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Cisco exam blueprint
This 350-401 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 350-401 exam.