JNCIS-ENT Layer 2 Security Practice Question
When implementing Layer 2 firewall filters on an EX Series switch, which packet characteristic can be matched in a filter term?
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
✓
Source MAC address
Layer 2 firewall filters in Junos can match fields such as source MAC address, destination MAC address, VLAN ID, and EtherType.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Source MAC address
Why this is correct
Bridge family filters evaluate Layer 2 fields like source and destination MAC addresses.
- ✗
Destination IP address
Why it's wrong here
Destination IP addresses are matched using family inet/inet6 filters, not pure Layer 2 bridge filters.
- ✗
ICMP type code
Why it's wrong here
ICMP type codes are part of Layer 3/4 payload inspection.
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TCP port number
Why it's wrong here
TCP port numbers belong to Layer 4 and require family inet filters with transport header fields.
Visual reference
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 — 506 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.