JN0-231 Juniper Security-Associate (JNCIA-SEC) Free Practice Exam Questions (2025 Updated)

"Local Authentication—In local authentication, the SRX Series device validates the user credentials by checking them in the local database. In this method, the administrator handles change of password or resetting of forgotten password. Here, it requires that an user must remember a new password. This option is not much preferred from a security standpoint.

• External Authentication—In external authentication, you can allow the users to use the same user credentials they use when accessing other resources on the network. In many cases, user credentials are domain logon used for Active Directory or any other LDAP authorization system. This method simplifies user experience and improves the organization’s security posture; because you can maintain the authorization system with the regular security policy used by your organization."

https://www.juniper.net/documentation/us/en/software/secure-connect/secure-connect-administrator-guide/topics/topic-map/secure-connect-getting-started.html

https://www.inetzero.com/blog/unified-threat-management-deeper-dive-traffic-inspe ction/

https://www.juniper.net/documentation/us/en/software/junos/interfaces-security-devices/topics/topic-map/security-interface-logical.html

Translation of the original source IP address to an IP address from a user-defined address pool by shifting the IP addresses. This type of translation is one-to-one, static, and without port address translation. If the original source IP address range is larger than the IP address range in the user-defined pool, untranslated packets are dropped. https://www.juniper.net/documentation/us/en/software/junos/nat/topics/topic-map/nat-security-source-and-source-pool.html

Web filtering is a feature that allows administrators to control access to websites by categorizing URLs into different categories such as gambling, social networking, or adult content. The decision to permit or deny access to a website is based on the category to which a URL belongs. This is done by comparing the URL against a database of categorized websites and making a decision based on the policy defined by the administrator.

ICMP flood

Use the ICMP flood IDS option to protect against ICMP flood attacks. An ICMP flood attack typically occurs when ICMP echo requests use all resources in responding, such that valid network traffic can no longer be processed.

The threshold value defines the number of ICMP packets per second (pps) allowed to be send to the same destination address before the device rejects further ICMP packets.

IP spoofing

Use the IP address spoofing IDS option to prevent spoofing attacks. IP spoofing occurs when an invalid source address is inserted in the packet header to make the packet appear to come from a trusted source.

https://www.juniper.net/documentation/us/en/software/junos/denial-of-service/topics/topic-map/security-introduction-to-adp.html

Understanding the Policies in the Exhibit:The exhibit displays two policies configured on the Juniper SRX device for traffic between the trust zone and the dmz zone.

Policy 1:

Name: Trust-DMZ-Access

State: Enabled

Source Address: Trust-Net

Destination Address: DMZ-Net

Applications: junos-ftp, junos-ping

Action: permit

Log: Enabled

Policy 2:

Name: Trust-DMZ-Block

State: Enabled

Source Address: Trust-Net

Destination Address: DMZ-Net

Applications: junos-ssh

Action: deny, log

Analysis of Each Option:

Option A:

The Trust-DMZ-Access policy explicitly permits traffic for the junos-ftp and junos-ping applications.

This is validated by the action permit in the policy configuration.

Correct.

Option B:

This is incorrect because the Trust-DMZ-Access policy permits FTP and ping traffic rather than denying it.

Incorrect.

Option C:

The Trust-DMZ-Block policy explicitly denies traffic for the junos-ssh application.

Therefore, SSH access is not permitted.

Incorrect.

Option D:

The Trust-DMZ-Block policy denies SSH traffic from the Trust-Net to the DMZ-Net.

This is validated by the action deny.

Correct.

Juniper Security References:

Security Policy Overview:Security policies in Junos OS are used to control and filter traffic between security zones. Each policy defines:

Source and destination zones

Source and destination addresses

Applications or services

Action: permit, deny

Logging options

Policy Action Details:

permit: Allows the specified traffic.

deny: Blocks the specified traffic.

Application Identification:

Juniper SRX uses predefined application identifiers (junos-ftp, junos-ping, junos-ssh) for traffic matching.

Policy Evaluation Order:Policies are evaluated in sequence by their index number or sequence number. In this exhibit:

Trust-DMZ-Access is evaluated first (Sequence number: 1).

Trust-DMZ-Block is evaluated next (Sequence number: 2).

Conclusion:Based on the exhibit, FTP and ping traffic is permitted under Trust-DMZ-Access, and SSH traffic is denied under Trust-DMZ-Block. The answers to the question are therefore:

A. Correct

D. Correct

Refer to the Juniper Security Policy Documentation for more details on configuring and managing policies.

Juniper ATP Geo IP can help to accomplish this task by using geolocation services to determine the geographical location of IP addresses. As IP prefixes get allocated to the countries that you have specified, the Geo IP solution will automatically update the configured firewall policies to block any traffic that is coming from those specific countries.

This is a great solution for blocking specific countries - as it will allow for a more personalized and targeted approach to firewall policies - and thus, to increase the effectiveness of the solution at blocking potential malicious traffic.

This is because the interface NAT would allow the connections to pass through the firewall - and thus, would ensure that the appropriate ports are open in order to allow for the connections to be established.

This is a really important step in order to ensure that all of the appropriate traffic is allowed through the SRX Series firewall - and thus, it must be a priority when deploying the firewall.

user@host# set security utm custom-objects url-pattern url-pattern-name https://www.juniper.net/documentation/us/en/software/junos/utm/topics/t opic-map/security-local-list-antispam-filtering.html

The main purpose of using screens on an SRX Series device is to provide protection against common Denial of Service (DoS) attacks. Screens help prevent network resources from being exhausted or unavailable by filtering or blocking network traffic based on predefined rules. The screens are implemented as part of the firewall function on the SRX Series device, and they help protect against various types of DoS attacks, such as TCP SYN floods, ICMP floods, and UDP floods.

Junos Space is a management platform that provides a single pane of glass view of SRX Series devices dispersed throughout locations in your organization. It provides visibility into the security policies of the devices, allowing you to quickly identify and respond to security threats. Additionally, it provides the ability to manage multiple devices remotely and in real-time, enabling you to quickly deploy and update security policies on all devices. For more information, please refer to the Juniper Networks Junos Space Network Director User Guide, which can be found on Juniper's website.

J-Web is a web-based interface for configuring and managing Juniper devices. The management and loopback address configuration option in J-Web allows you to configure the IP address of the device management port, which is used to remotely access and manage the device.

"Service objects represent applications and services that can be assigned to a security policy rule. Applications and services can either be predefined by Junos software or custom defined by the administrator."