JNCIS-ENT Layer 2 Security Practice Question
Which statement accurately describes port security MAC-limit behavior?
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
✓
It restricts the maximum number of MAC addresses that can be learned on a secure interface.
Port security MAC-limit restricts the maximum number of MAC addresses learned on a secure interface.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
It statically assigns all learned MAC addresses to the switch configuration file automatically.
Why it's wrong here
It limits dynamically learned addresses unless static persistence is configured.
- ✗
It defines the maximum bandwidth a single MAC address can consume on a port.
Why it's wrong here
Bandwidth limits are handled by policers, not MAC-limits.
- ✗
It prevents MAC address spoofing by validating IP bindings against DHCP tables.
Why it's wrong here
IP-to-MAC validation is performed by IP Source Guard and DAI, not MAC-limit.
- ✓
It restricts the maximum number of MAC addresses that can be learned on a secure interface.
Why this is correct
MAC-limit caps the total number of unique source MAC addresses learned on the interface.
Quick reference
Access Control Model Comparison
| Model | Acronym | Who Controls Access? | Best For |
|---|---|---|---|
| Discretionary Access Control | DAC | Resource owner | Small teams, file shares |
| Mandatory Access Control | MAC | System / security labels | Classified govt / military |
| Role-Based Access Control | RBAC | Administrator (via roles) | Enterprise environments |
| Attribute-Based Access Control | ABAC | Policy engine (user + resource attributes) | Fine-grained, dynamic policies |
| Rule-Based Access Control | RuBAC | System rules / ACLs | Firewall rules, network ACLs |
About these practice questions
Courseiva writes every JNCIS-ENT question from scratch — 519 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. 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 August 2026 · checked against the official Juniper Networks exam blueprint
This JNCIS-ENT practice question is part of Courseiva's free Juniper Networks 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 JNCIS-ENT exam.