Courseiva
Layer 2 Authentication And Access ControlhardMultiple ChoiceObjective-mapped

JNCIP-ENT Layer 2 Authentication And Access Control Practice Question

An enterprise network uses 802.1X authentication with dynamic VLAN assignment on EX Series switches. A client authenticates, and the RADIUS server returns both a VLAN name and a set of dynamic firewall filter names via RADIUS attributes (Filter-Id). When the client connects, the VLAN assignment works perfectly, but the firewall filters are not applied to the interface. What is the most likely cause?

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

The named firewall filters were not pre-configured and committed locally on the EX Series switch.

For dynamic Filter-Id attributes returned by RADIUS to be applied successfully on an EX Series switch, the named firewall filters must already be pre-configured and committed locally on the switch. If the filter does not exist locally, the application fails.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

  • The dynamic filter must be defined inside the global access profile instead of being returned by RADIUS.

    Why it's wrong here

    Incorrect. Filter-Id is intended to be returned by RADIUS.

  • The named firewall filters were not pre-configured and committed locally on the EX Series switch.

    Why this is correct

    Correct. Dynamic filters referenced by RADIUS Filter-Id must exist locally on the switch.

  • RADIUS Filter-Id attributes are not supported on EX Series switches for dynamic firewall application.

    Why it's wrong here

    Incorrect. EX Series switches fully support Filter-Id attributes.

  • Dynamic filter assignment requires MAC RADIUS and is not supported with 802.1X.

    Why it's wrong here

    Incorrect. Filter-Id is supported across 802.1X and MAC RADIUS.

Visual reference

Switch VLAN 10 Sales (192.168.10.0/24) PC-A PC-B VLAN 20 HR (192.168.20.0/24) PC-C PC-D Router VLANs isolate traffic — inter-VLAN routing requires a Layer 3 device

Quick reference

AAA Protocol Comparison

ProtocolPort(s)EncryptionTransportPrimary Use
RADIUS1812 / 1813Password onlyUDPNetwork access control
TACACS+49Full packetTCPDevice administration
Diameter3868Full sessionTCP / SCTPCarrier / mobile networks
802.1XEAP-basedLayer 2Port-based access control

TACACS+ encrypts the entire packet; RADIUS only encrypts the password field — a key exam distinction.

About these practice questions

This JNCIP-ENT question is part of Courseiva's 336-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →

How Courseiva writes practice questions · Editorial policy

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 JNCIP-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 JNCIP-ENT exam.