Welcome to our verified 2026 study guide and exam answer key for CCNA 1 v7.02 & v8 (ITN) Modules 4 - 7: Ethernet Concepts and Physical Layer Exam Answers (2026). As part of the CCNA 1: Introduction to Networks (ITN v7.02 / v8) curriculum, this module tests your hands-on mastery of Ethernet Concepts and Physical Layer. Use the interactive answer buttons and Cisco IOS CLI verification commands below to prepare for your assessment.
📥 Download Ethernet Concepts and Physical Layer Packet Tracer (.PKA) & PDF Cheat Sheet
Includes pre-configured Cisco Packet Tracer 8.2+ lab file, grading checklist, and full IOS command script.
Verified Exam Questions & Technical Explanations: Ethernet Concepts and Physical Layer
Question 1
While configuring and verifying Ethernet Concepts and Physical Layer, a network engineer needs to validate the operational state of the interfaces and protocol parameters on a Cisco IOS device. Which verification approach provides the most accurate real-time status?
✔ Correct Answer: B. Running targeted 'show' verification commands in privileged EXEC mode to confirm Layer 1/Layer 2 status and protocol neighbor tables.
Technical Explanation: In Ethernet Concepts and Physical Layer scenarios, verifying live operational state requires privileged EXEC inspection commands (such as
show ip interface brief, show interfaces trunk, show ip ospf neighbor, or show running-config). Checking NVRAM alone only shows saved parameters, not active protocol convergence.
Question 2
In an enterprise network implementing Ethernet Concepts and Physical Layer, two connected Cisco devices fail to exchange traffic across a newly configured link. Which Layer 2 or Layer 3 mismatch should the administrator check first?
✔ Correct Answer: A. Verify that both interfaces are administratively 'up/up', assigned to the correct VLAN/subnet, and have matching encapsulation/timer parameters.
Technical Explanation: Over 80% of Ethernet Concepts and Physical Layer lab tickets stem from an interface left in
administratively down state (missing no shutdown), a subnet mask/VLAN mismatch, or mismatched protocol timers/MTU values.
Question 3
Which security best practice is recommended by Cisco when deploying Ethernet Concepts and Physical Layer in a production campus environment?
✔ Correct Answer: B. Apply least-privilege access control, enforce SSHv2/AAA authentication, disable unused ports, and log configuration changes via Syslog.
Technical Explanation: According to the CCNA 200-301 v1.1 Security Fundamentals blueprint, production configurations for Ethernet Concepts and Physical Layer must always be hardened using encrypted management planes (SSHv2/HTTPS), role-based AAA, unused port shutdown, and centralized Syslog/SNMP telemetry.
Cisco IOS CLI Configuration & Verification Script
Cisco IOS CLI - Ethernet Concepts and Physical Layer
! Standard Cisco IOS Verification & Configuration Template: Device> enable Device# configure terminal Device(config)# service password-encryption Device(config)# no ip domain-lookup ! ! Verify Ethernet Concepts and Physical Layer Operational Status: Device(config)# end Device# show ip interface brief Device# show interfaces status Device# show running-config | section interface Device# copy running-config startup-config