JN0-636 Juniper Security, Professional (JNCIP-SEC) Free Practice Exam Questions (2025 Updated)

According to the exhibit, which is a security flow trace on an SRX Series device, the following statements are true:

The packet’s destination is to an interface on the SRX Series device. This is indicated by the line packet dropped for self but not interested, which means that the packet is destined to the SRX device itself, but the device does not have the corresponding service configured in the host-inbound-traffic stanza for the interface1.

The packet originated within the Trust zone. This is indicated by the line zone name: Trust, which shows that the packet belongs to the Trust zone. The Trust zone is typically the zone where the internal network is connected to the SRX device2.

The packet is dropped before making an SSH connection. This is indicated by the line flow_first_inline_processing: pak(0x4a9c0d0), which shows that the packet is the first packet in the session and is processed by the firewall. The packet is dropped because it does not match any security policy or host-inbound-traffic rule1. The packet is trying to make an SSH connection, which uses TCP port 22, as shown by the line source port: 22.

The following statements are false:

The packet’s destination is to a server in the DMZ zone. There is no indication of the DMZ zone in the trace output. The DMZ zone is typically the zone where the external servers are connected to the SRX device2.

The packet is allowed to make an SSH connection. The packet is not allowed to make an SSH connection, as explained above.

References: 1: SRX Getting Started - Troubleshoot Security Policy 2: SRX Getting Started - Configure Security Zones

To troubleshoot the traffic problem using the match criteria, you need to use the show security match-policies CLI command. The other options are incorrect because:

A. The show security policy-report CLI command displays the policy report, which is a summary of the policy usage statistics, such as the number of sessions, bytes, and packets that match each policy. It does not show the match criteria or the reason why the traffic is not hitting the policy1.

B. The show security application-tracking counters CLI command displays the application tracking counters, which are the statistics of the application usage, such as the number of sessions, bytes, and packets that match each application. It does not show the match criteria or the reason why the traffic is not hitting the policy2.

D. The request security policies check CLI command checks the validity and consistency of the security policies, such as the syntax, the references, and the conflicts. It does not show the match criteria or the reason why the traffic is not hitting the policy3.

Therefore, the correct answer is C. You need to use the show security match-policies CLI command to troubleshoot the traffic problem using the match criteria. The show security match-policies CLI command displays the policies that match the specified criteria, such as the source and destination addresses, the zones, the protocols, and the ports. It also shows the action and the hit count of each matching policy. You can use this command to verify if the traffic is matching the expected policy or not, and if not, what policy is blocking or rejecting the traffic4

The exhibit shows the output of the show security intelligence category summary command on the SRX-1 device. This command displays the status of the security intelligence categories configured on the device. In the output, we can see that there are two categories configured - Proxy_Nodes and Proxy_Node3. The Proxy_Nodes category is a custom category that is created by the SRX-1 device using the adaptive threat profiling feature. The Proxy_Node3 category is a third-party category that is downloaded from the Juniper ATP Cloud service. The Proxy_Nodes category contains the IP addresses that match the security policy named Proxy-ATP on the SRX-1 device. The Proxy_Node3 category contains the IP addresses that are associated with the Tor network.

The two statements that are true based on the exhibit are:

The SRX-1 device creates the Proxy_Nodes feed, so it cannot use it in another security policy. This is because the adaptive threat profiling feature does not allow the device that creates the feed to use it in another security policy. The feed is intended to be shared with other devices in the same realm through the Juniper ATP Cloud service. The SRX-1 device can only use the feeds that are created by other devices or downloaded from third-party sources.

You can only use the Proxy_Node3 feed as the destination-address match criteria of another security policy on a different SRX Series device. This is because the Proxy_Node3 feed is a third-party feed that is downloaded from the Juniper ATP Cloud service. The SRX-1 device can use this feed as a dynamic address object in its security policies. However, the feed is configured with the destination-only option, which means that it can only be used as the destination-address match criteria of a security policy. The source-address match criteria of a security policy cannot use this feed.

References: Juniper Security, Professional (JNCIP-SEC) Reference Materials source and documents: https://www.juniper.net/documentation/en_US/junos/topics/reference/command-summary/show-security-intelligence-category-summary.html https://www.juniper.net/documentation/en_US/junos/topics/concept/security-intelligence-third-party-feed-configuring.html https://www.juniper.net/documentation/en_US/junos/topics/concept/security-adaptive-threat-profiling-overview.html

https://www.juniper.net/documentation/en_US/release-independent/jatp/topics/topic-map/jatp-custom-log-ingestion.html

According to the exhibit, which is a configuration snippet of the SRX Series device, the global mode for the device is set to switching mode. This means that the device is operating as a Layer 2 switch and does not apply any security policies to the traffic between hosts in the same broadcast domain1. Therefore, the traffic between two hosts in the same broadcast domain are not matching any security policies.

To solve this problem, the user should change the global mode to transparent bridge mode. This means that the device will operate as a Layer 2 transparent bridge and apply security policies to the traffic between hosts in the same broadcast domain2. This will allow the user to enforce security policies based on the source and destination IP addresses, ports, and protocols of the traffic.

To change the global mode to transparent bridge mode, the user should use the following command:

set protocols l2-learning global-mode transparent-bridge

This command will set the global mode for the SRX Series device as Layer 2 transparent bridge mode. After changing the mode, the user must reboot the device for the configuration to take effect2.

References: 1: global-mode (Protocols) 2: Configuring Layer 2 Transparent Mode

A logical system is a virtualization feature in SRX Series devices that allows you to create multiple, isolated virtual routers within a single physical device. Each logical system has its own routing table, firewall policies, and interfaces, and it can be managed and configured independently of the other logical systems. Logical systems are an effective way to isolate different administrative domains and to support a large number of virtualized instances.

According to the Juniper documentation, the solution that would best meet the requirements of deploying a virtualization solution with the security devices in the network is logical systems. Logical systems are a feature that allows the SRX Series device to be partitioned into multiple logical devices, each with its own discrete administrative domain, routing table, firewall policies, VPNs, and interfaces1. Each logical system can support up to 100 virtualized instances, depending on the SRX Series model and the available resources2.

The following solutions are not suitable or incorrect for this scenario:

VRF instances: VRF instances are a type of routing instance that allows the SRX Series device to maintain multiple routing tables for different VPNs or customers. However, VRF instances do not provide separate administrative domains, firewall policies, or interfaces for each instance3.

Virtual router instances: Virtual router instances are a type of routing instance that allows the SRX Series device to create multiple logical routers, each with its own routing table and interfaces. However, virtual router instances do not provide separate administrative domains or firewall policies for each instance.

Tenant systems: Tenant systems are a feature that allows the SRX Series device to create multiple logical devices, each with its own discrete administrative domain, routing table, firewall policies, VPNs, and interfaces. However, tenant systems are only supported on the SRX1500, SRX4100, and SRX4200 devices, and each tenant system can only support up to 10 virtualized instances.

References: 1: Understanding Logical Systems 2: SRX Series Logical Systems Feature Guide 3: vrf (Routing Instances) : [virtual-router (Routing Instances)] : [Understanding Tenant Systems]

In Juniper ATP Cloud, a threat prevention policy allows you to define how the system should handle an infected host. Two of the available actions are:

Close the connection: This action will close the connection between the infected host and the destination to which it is trying to connect. This will prevent the host from communicating with the destination and will stop any malicious activity.

Quarantine the host: This action will isolate the infected host from the network by placing it in a quarantine VLAN. This will prevent the host from communicating with other devices on the network, which will prevent it from spreading malware or exfiltrating data.

Sending a custom message is used to notify the user and administrator of the action taken. Drop the connection silently is not an action available in Juniper ATP Cloud.

According to the Juniper documentation, the threat prevention policy in Juniper ATP Cloud is a configuration that defines the actions and notifications for different threat levels of the traffic. The threat levels are based on the verdicts returned by Juniper ATP Cloud after analyzing the files, URLs, and domains. The threat levels range from 1 to 10, where 1 is the lowest and 10 is the highest1.

The threat prevention policy allows the user to specify different actions for different threat levels. The actions can be applied to the traffic or to the infected host. The actions available for the traffic are:

Permit: Allows the traffic to pass through the SRX Series device without any interruption.

Block: Blocks the traffic and sends a reset packet to the client and the server.

Drop: Drops the traffic silently without sending any reset packet.

Redirect: Redirects the traffic to a specified URL, such as a warning page or a sinkhole server.

The actions available for the infected host are:

None: Does not take any action on the infected host.

Quarantine: Quarantines the infected host by applying a firewall filter that blocks all outbound traffic from the host, except for the traffic to Juniper ATP Cloud or the specified redirect URL.

Custom: Executes a custom script on the SRX Series device to perform a user-defined action on the infected host, such as sending an email notification or triggering an external system.

Therefore, the two different actions available in a threat prevention policy to deal with an infected host are:

Block: This action will block the traffic from or to the infected host and send a reset packet to the client and the server. This will prevent the infected host from communicating with the malicious server or spreading the malware to other hosts.

Quarantine: This action will quarantine the infected host by blocking all outbound traffic from the host, except for the traffic to Juniper ATP Cloud or the redirect URL. This will isolate the infected host from the network and allow the user to remediate the infection.

The following actions are not available or incorrect:

Send a custom message: This is not an action available in the threat prevention policy. However, the user can use the custom action to execute a script that can send a custom message to the infected host or the administrator.

Drop the connection silently: This is an action available for the traffic, not for the infected host. It will drop the traffic without sending any reset packet, which may not be effective in stopping the infection or notifying the user.

References: 1: Configuring Threat Prevention Policies

According to the Juniper documentation, a custom block list feed is a user-defined list of IP addresses or URLs that are considered malicious or unwanted. A custom block list feed can be configured to override the default Juniper Seclntel block list feed, which is a cloud-based service that provides a list of known malicious IP addresses and URLs. To override the Juniper Seclntel block list feed, the custom block list feed must have a higher priority value than the Juniper Seclntel block list feed. In the exhibit, the custom block list feed has a priority value of 10, which is higher than the default priority value of 5 for the Juniper Seclntel block list feed. Therefore, this custom block list feed will be used instead of the Juniper Seclntel block list feed. References: : [Configuring Custom Block List Feeds]

To solve the problem of using the same IPv4 address space as your company, you can identify two neutral IPv4 address spaces for address translation. This will allow you to use the same IPv4 address space as your company without any conflicts. Additionally, you can configure static NAT on the SRX Series devices to ensure that the traffic is properly routed between the two networks.

Static NAT is a type of network address translation that maps a private IP address to a public IP address on a one-to-one basis. Static NAT is useful when you need to expose a server or device with a private IP address to the Internet or another network with a different IP address range. Static NAT also preserves the original source or destination IP address in the packet header, which can be useful for logging or auditing purposes1.

Neutral IPv4 address spaces are IP address ranges that are not assigned to any specific organization or entity. They are usually reserved for special purposes, such as private networks, multicast, loopback, or documentation. Neutral IPv4 address spaces can be used for address translation when there is an overlap or conflict between two networks that need to communicate with each other. For example, you can use the 10.0.0.0/8, 172.16.0.0/12, or 192.168.0.0/16 address ranges, which are designated for private use, as neutral IPv4 address spaces for address translation2.

References:

SRX Getting Started - Configure VPN tunnel for site-to-site connectivity

SRX & J Series Site-to-Site VPN Configurator

Resolution Guide – SRX - Troubleshoot Static NAT

RFC 1918 - Address Allocation for Private Internets

According to the Juniper documentation, reflexive NAT is a type of source NAT that allows an internal host to communicate with an external host using a single public IP address and port. The reflexive NAT session is created when the internal host initiates the traffic to the external host, and the session is deleted when the traffic stops. The reflexive NAT session is bidirectional, meaning that the external host can send traffic back to the internal host using the same public IP address and port that the internal host used to reach the external host. However, the external host cannot initiate a new session to the internal host using the same public IP address and port, unless the internal host has already established a session with the external host. Therefore, only the Internet host that the internal host originally communicated with can initiate traffic to reach the internal host using the 203.0.113.1 address, a random source port, and destination port 54311. References: [Configuring Reflexive NAT]

 You are connecting two remote sites to your corporate headquarters site. You must ensure that traffic passes through the corporate headquarters. In this scenario, the VPN that should be used is:

D. Hub-and-spoke IPsec VPN with the corporate firewall acting as the hub device. A hub-and-spoke IPsec VPN is a type of VPN that connects multiple remote sites to a central site, or hub, over a public network. The hub site acts as a gateway for the remote sites and provides security and routing services. The remote sites, or spokes, communicate with each other through the hub site. The hub site and the spoke sites use IPsec tunnels to encrypt and authenticate the traffic between them. A hub-and-spoke IPsec VPN is suitable for connecting two remote sites to your corporate headquarters site, because it allows you to control the traffic flow and enforce security policies at the hub site. The corporate firewall can act as the hub device and provide IPsec VPN services to the remote sites1.

The other options are incorrect because:

A. Full mesh IPsec VPNs with tunnels between all sites. A full mesh IPsec VPN is a type of VPN that connects every site to every other site over a public network. Each site has an IPsec tunnel with every other site, forming a mesh topology. A full mesh IPsec VPN provides direct and secure communication between any pair of sites, but it also requires a large number of IPsec tunnels and complex configuration. A full mesh IPsec VPN is not suitable for connecting two remote sites to your corporate headquarters site, because it does not ensure that traffic passes through the corporate headquarters site, and it may introduce unnecessary overhead and complexity2.

B. A full mesh Layer 3 VPN with the BGP route reflector behind the corporate firewall device. A full mesh Layer 3 VPN is a type of VPN that uses MPLS and BGP to provide Layer 3 connectivity and routing between multiple sites over a service provider’s network. Each site has a BGP session with every other site, forming a full mesh topology. A BGP route reflector is a device that reduces the number of BGP sessions required in a full mesh topology by reflecting routes between its clients. A full mesh Layer 3 VPN with the BGP route reflector behind the corporate firewall device is not suitable for connecting two remote sites to your corporate headquarters site, because it does not ensure that traffic passes through the corporate firewall device, and it may require additional configuration and coordination with the service provider3.

C. A Layer 3 VPN with the corporate firewall acting as the hub device. A Layer 3 VPN is a type of VPN that uses MPLS and BGP to provide Layer 3 connectivity and routing between multiple sites over a service provider’s network. A Layer 3 VPN can have different topologies, such as full mesh, hub-and-spoke, or partial mesh. A Layer 3 VPN with the corporate firewall acting as the hub device is not suitable for connecting two remote sites to your corporate headquarters site, because the corporate firewall may not support MPLS and BGP, and it may require additional configuration and coordination with the service provider3.

References:

Hub-and-Spoke VPNs Overview

Full Mesh VPNs Overview

Layer 3 VPNs Overview

According to the Juniper documentation, filter-based forwarding (FBF) is a technique that allows the SRX Series device to forward packets based on firewall filter rules, rather than the default routing table1. FBF can be used to implement policy-based routing, load balancing, or traffic engineering2. To deploy FBF on the SRX Series device for incoming traffic sourced from the 10.10.100.0/24 network, the following steps are required:

You must create a forwarding-type routing instance. A forwarding-type routing instance is a special type of routing instance that is used for FBF. It does not have any interfaces or routing protocols associated with it, but it has its own routing table that can be populated by static routes, RIB groups, or routing policies3. You can create a forwarding-type routing instance by using the following command:

set routing-instances instance-type forwarding

You must create and apply a firewall filter that matches on the source address 10.10.100.0/24 and then sends this traffic to your routing instance. A firewall filter is a set of rules that can match on various packet attributes, such as source and destination addresses, ports, protocols, and so on. You can use the then routing-instance action to specify the routing instance that the packet should be forwarded to4. You can create and apply a firewall filter by using the following commands:

set firewall family inet filter term from source-address 10.10.100.0/24 set firewall family inet filter term then routing-instance  set interfaces unit family inet filter input

You must create a RIB group that adds interface routes to your routing instance. A RIB group is a mechanism that allows you to import routes from one routing table to another. You can use a RIB group to add the interface routes of the ingress interface to the routing table of the forwarding-type routing instance. This will ensure that the SRX device can forward the packets to the correct next hop based on the destination address5. You can create a RIB group by using the following commands:

set routing-options rib-groups import-rib inet.0 set routing-options rib-groups import-rib .inet.0 set routing-instances routing-options instance-import

The following steps are not required or incorrect:

You do not need to create a VRF-type routing instance. A VRF-type routing instance is a type of routing instance that is used for virtual routing and forwarding. It allows you to create multiple logical routers on the same physical device, each with its own interfaces, routing protocols, and routing tables. VRF-type routing instances are typically used for VPNs, MPLS, or network segmentation. However, they are not necessary for FBF, which can be achieved with a forwarding-type routing instance.

You do not need to create and apply a firewall filter that matches on the destination address 10.10.100.0/24 and then sends this traffic to your routing instance. This would be redundant and unnecessary, as the destination address of the incoming traffic is already determined by the routing table of the forwarding-type routing instance. Moreover, this would create a loop, as the traffic would be sent back to the same routing instance that it came from.

References: 1: Filter-Based Forwarding Overview 2: Configuring Filter-Based Forwarding 3: forwarding (Routing Instances) 4: routing-instance (Firewall Filter Action) 5: Configuring RIB Groups : [vrf (Routing Instances)]

https://ww w.juniper.net/documentation/en_US/junos-space18.1/policy-enforcer/topics/task/configuration/junos-space-policyenforcer-custom-feeds-infected-host-configure.html

The flow-session resource is needed in order to ensure adequate and secure communication between the two logical systems.

The flow-session resource must be defined in the security profile for the interconnect logical system because the interconnect logical system is responsible for forwarding traffic between other logical systems. The flow-session resource determines the maximum number of sessions that the interconnect logical system can create and maintain. If the flow-session resource is not allocated or is insufficient, the interconnect logical system might drop packets or fail to establish sessions1.

The NAT resources are not needed to be allocated to the interconnect logical system because the interconnect logical system does not perform any NAT operations on the traffic. The NAT resources are only relevant for the logical systems that need to translate the source or destination IP addresses or ports of the traffic1.

No resources are not needed to be allocated to the interconnect logical system is incorrect because the interconnect logical system still requires some resources to function properly, such as the flow-session resource. The interconnect logical system cannot operate without any resources allocated to it1.

The resources must be calculated based on the amount of traffic that will flow between the logical systems is partially correct, but not the best answer. The resources must be calculated based on the amount of traffic and the type of traffic that will flow between the logical systems. For example, the flow-session resource depends on the number and duration of sessions, the security-log-stream-number resource depends on the number and size of logs, and the NAT resource depends on the number and type of NAT rules1.

References:

Security Profiles for Logical Systems | Junos OS | Juniper Networks