FC0-U71 Tech Concepts and Terminology Practice Question
A network technician is troubleshooting a connectivity issue and needs to identify the destination MAC address of a frame. Which TWO of the following are true about MAC addresses? (Select 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
✓
They are 48 bits in length
MAC addresses are 48-bit (6 bytes) and commonly represented in hexadecimal. They are assigned by manufacturers and are used at the data link layer.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
They are 48 bits in length
Why this is correct
MAC addresses are 48 bits long, comprising a 24-bit Organisationally Unique Identifier assigned by the IEEE and a 24-bit NIC-specific value. This fixed length is what lets the technician read the frame's destination field directly, satisfying the stem's requirement to identify the destination MAC address.
- ✗
They are assigned by the operating system
Why it's wrong here
MAC addresses are burned into the network interface card by the manufacturer, not assigned by the operating system; the OS may present or override them in software, but the hardware address is vendor-assigned. OS assignment is tempting because software can change the visible address, but that is spoofing, not the standard source.
- ✓
They are typically written as 12 hexadecimal digits
Why this is correct
A MAC address is conventionally expressed as six octets written in hexadecimal, giving 12 hex digits, often grouped in pairs and separated by colons or hyphens, which is the notation technicians read when inspecting frame headers.
- ✗
They are represented in octal
Why it's wrong here
MAC addresses are conventionally written in hexadecimal, often as six colon- or hyphen-separated pairs, not octal. Octal representation is tempting because it is another base system used in computing, but hexadecimal is the correct choice for expressing the 48-bit hardware address.
- ✗
They are used at the application layer
Why it's wrong here
MAC addresses operate at the data link layer (Layer 2) to deliver frames on the local network segment; the application layer (Layer 7) deals with protocols such as HTTP and DNS. Application-layer use is tempting because troubleshooting often involves higher-layer protocols, but MAC addressing is the correct choice only for Layer 2 frame delivery.
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
One of 988 original FC0-U71 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 by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This FC0-U71 practice question is part of Courseiva's free CompTIA 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 FC0-U71 exam.