hardMultiple ChoiceObjective-mapped
350-701 Practice Question: A large enterprise uses Cisco ISE for network…
A large enterprise uses Cisco ISE for network access control with 802.1X authentication (PEAP-MSCHAPv2) on wired ports. Access switches are Cisco Catalyst 3850s running IOS-XE 16.9, and ISE is version 2.7 with all patches. Recently, users in the finance department report intermittent connectivity issues when connecting to the network. The issue is sporadic: a user may connect successfully one day, then fail multiple times the next day. Switch logs show frequent 'EAP timeout' errors for these users. The network team has verified that the RADIUS servers are reachable and have sufficient CPU and memory. The ISE logs show no authentication failures, only that some EAP conversations are dropped mid-exchange. What is the most likely cause of these intermittent failures?
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 switch is configured with a RADIUS timeout value that is too low.
The EAP timeout errors and intermittent nature point to the RADIUS timeout being too low on the switch, causing it to drop EAP conversations during periods of high latency. Options A, B, and D would cause consistent failures for affected users, not intermittent issues.
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 switch is configured with a RADIUS timeout value that is too low.
Why this is correct
A low timeout can cause the switch to abort EAP exchanges when network latency spikes, leading to intermittent timeouts.
- ✗
The switch port is configured with a dynamic VLAN assignment that does not exist on the switch.
Why it's wrong here
This would cause consistent failure for users assigned to that VLAN, not intermittent.
- ✗
The user's machine certificate has expired.
Why it's wrong here
PEAP-MSCHAPv2 does not use client certificates; it uses machine credentials. Even if it did, expired certificates cause consistent failures.
- ✗
The ISE server is configured with an incorrect shared secret for the switch.
Why it's wrong here
An incorrect shared secret would cause all authentications to fail consistently.
Quick reference
AAA Protocol Comparison
| Protocol | Port(s) | Encryption | Transport | Primary Use |
|---|---|---|---|---|
| RADIUS | 1812 / 1813 | Password only | UDP | Network access control |
| TACACS+ | 49 | Full packet | TCP | Device administration |
| Diameter | 3868 | Full session | TCP / SCTP | Carrier / mobile networks |
| 802.1X | — | EAP-based | Layer 2 | Port-based access control |
TACACS+ encrypts the entire packet; RADIUS only encrypts the password field — a key exam distinction.
Go deeper
Related to this question
About these practice questions
One of 978 original 350-701 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 →
Same concept, more angles
1 more way this is tested on 350-701
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A university is deploying 802.1X authentication for wired access using Cisco ISE. The network consists of Cisco Catalyst switches. The authentication is working for most users, but some users in a specific building are experiencing frequent authentication failures, especially during peak hours. The switches in that building are configured with RADIUS settings pointing to ISE. ISE logs show that authentication requests are being sent but sometimes time out. The network team suspects that the issue is related to RADIUS server load balancing, as the ISE deployment includes two nodes in a distributed model. What is the most likely cause of the timeouts?
hard- A.The RADIUS shared secret is misconfigured on some switches.
- B.The switches are not configured with the correct VLAN assignments.
- C.The switches are using the wrong RADIUS accounting port.
- ✓ D.The ISE nodes are not configured for load balancing, causing one node to be overwhelmed.
Why D: The symptoms—intermittent timeouts during peak hours in a specific building—point to a load-balancing issue. In a distributed ISE deployment, if the switches are not configured with multiple RADIUS server entries or if ISE nodes are not properly load-balanced (e.g., using a single primary server or missing secondary server configuration), one node can become overwhelmed with authentication requests, leading to timeouts. The fact that authentication works for most users but fails during peak hours in one building strongly suggests that the switches in that building are sending all requests to a single ISE node that cannot handle the load.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 350-701 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 350-701 exam.