350-501 Architecture Practice Question
A metro Ethernet provider needs to scale customer VLANs beyond the 4,096 limit by encapsulating customer VLAN tags with an outer service provider tag. Which IEEE standard is used?
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
✓
802.1ad (Q-in-Q)
Q-in-Q (802.1ad) adds an outer VLAN tag to extend VLAN space. 802.1ah is for MAC-in-MAC, 802.1Q is the basic standard, and 802.1ak is not related.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
802.1ad (Q-in-Q)
Why this is correct
802.1ad allows double tagging with an outer service provider tag.
- ✗
802.1ah (Provider Backbone Bridging)
Why it's wrong here
802.1ah uses MAC-in-MAC encapsulation, not double tagging.
- ✗
802.1Q
Why it's wrong here
802.1Q defines a single VLAN tag.
- ✗
802.1ak
Why it's wrong here
802.1ak is not a standard for double tagging.
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 |
Go deeper
Related to this question
About these practice questions
Courseiva writes every 350-501 question from scratch — 971 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 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.