Quick Answer
The answer is FortiToken. FortiToken Mobile is the correct feature because it provides two-factor authentication by generating a one-time password (OTP) directly on a smartphone app, which users enter alongside their primary credentials to access the FortiGate VPN or administrative interface. This OTP changes every 60 seconds and is cryptographically tied to the FortiGate’s token seed, ensuring that even if a password is stolen, the session remains secure. On the Fortinet NSE 4 Network Security Professional exam, this question tests your understanding of FortiGate’s multi-factor authentication options, often appearing alongside a distractor like “FortiAuthenticator” or “LDAP”—remember that FortiAuthenticator is a separate server, while FortiToken is the actual token (hardware or mobile) that generates the OTP. A common trap is confusing the token with the authentication server; the key memory tip is “Token = the thing that generates the code, not the thing that checks it.”
This NSE4 practice question tests your understanding of authentication and vpn. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
Which of the following FortiGate features allows users to authenticate using a one-time password generated by a mobile app?
FSSO
Why wrong: FSSO uses Active Directory logon events.
LDAP
Why wrong: LDAP is a directory service protocol.
FortiToken
FortiToken generates OTPs for two-factor authentication.
Captive portal
Why wrong: Captive portal presents a login page but does not generate OTPs.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
FortiToken
FortiToken Mobile is a two-factor authentication solution that generates one-time passwords (OTP) on a smartphone app. FortiToken can be either hardware token or mobile token.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
FSSO
Why it's wrong here
FSSO uses Active Directory logon events.
LDAP
Why it's wrong here
LDAP is a directory service protocol.
FortiToken
Why this is correct
FortiToken generates OTPs for two-factor authentication.
Related concept
Read the scenario before looking for a memorised answer.
Captive portal
Why it's wrong here
Captive portal presents a login page but does not generate OTPs.
Common exam traps
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Detailed technical explanation
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A practitioner preparing for the NSE4 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Identify which NSE4 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Authentication and VPN — study guide chapter
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Authentication and VPN practice questions
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FAQ
Authentication and VPN — This question tests Authentication and VPN — Read the scenario before looking for a memorised answer..
The correct answer is: FortiToken — FortiToken Mobile is a two-factor authentication solution that generates one-time passwords (OTP) on a smartphone app. FortiToken can be either hardware token or mobile token.
Identify which NSE4 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Same concept, more angles
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. An organization wants to use FortiToken for two-factor authentication on SSL VPN logins. Which authentication method must be enabled on the FortiGate to support this?
easyWhy A: FortiToken requires two-factor authentication. On FortiGate, this is configured by enabling 'Two-factor Authentication' under the user group or authentication settings, typically set to 'FortiToken' for token-based OTP.
Variation 2. Which authentication server type can be used with FortiGate to authenticate remote VPN users with two-factor authentication using FortiTokens?
easyWhy C: FortiToken two-factor authentication can be used with local users or with remote authentication servers like RADIUS. However, FortiToken is natively supported by FortiGate local users and can also be used with RADIUS if the FortiGate acts as the RADIUS client forwarding tokens.
Last reviewed: Jun 21, 2026
This NSE4 practice question is part of Courseiva's free Fortinet 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 NSE4 exam.
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