Courseiva
Security and ServicesmediumMultiple SelectObjective-mapped

350-501 Security and Services Practice Question

A service provider wants to protect its core routers from control plane attacks. Which two mechanisms are effective in mitigating such attacks on IOS XR? (Choose two.)

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

Unicast Reverse Path Forwarding (uRPF)

CoPP polices control plane traffic. uRPF prevents spoofed source IPs, which are often used in attacks. BGP prefix filtering is for routing updates, not control plane attacks. MPLS TTL propagation is for traceroute. NTP authentication secures time sync.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

  • MPLS TTL propagation

    Why it's wrong here

    This affects traceroute visibility, not control plane security.

  • Unicast Reverse Path Forwarding (uRPF)

    Why this is correct

    uRPF drops packets with spoofed source IPs, reducing attack traffic.

  • Control Plane Policing (CoPP)

    Why this is correct

    CoPP rate-limits control plane traffic.

  • BGP prefix filtering

    Why it's wrong here

    This filters routing updates, not attack traffic.

  • NTP authentication

    Why it's wrong here

    NTP authentication secures time synchronization, not control plane attacks.

Visual reference

Source Router + ACL permit 10.0.0.0/8 deny any Server 10.0.0.5 ✓ 192.168.1.1 ✗ dropped ACLs evaluate top-down; first match wins — implicit deny all at end

About these practice questions

This 350-501 question is part of Courseiva's 971-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →

How Courseiva writes practice questions · Editorial policy

JA

Written by Johnson Ajibi, MSc IT Security

Senior Network & Security Engineer · founder of Courseiva

This 350-501 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 350-501 exam.