2 packs: 15% off with code BUY2. 3 or more: 20% off with code BUY3.

Free Juniper JN0-637 JNCIP-SEC Practice Questions

26 free Juniper JN0-637 JNCIP-SEC practice questions from the CertStash pack of 103, each with the correct answer and a full explanation. The rule is the same for every exam: ten free on the product page, 26 free here, all 103 in the pack, and each step includes the one before it.

Get all 103 questions (US$39) · Download the first 10 as a PDF

Question 1

You want to create a connection for communication between tenant systems without using physical revenue ports on the SRX Series device. What are two ways to accomplish this task? (Choose two.)

  1. Use an interconnect VPLS switch.
  2. Use a secure wire.
  3. Use a point-to-point logical tunnel.
  4. Use an external router.
Show answer and explanation

Correct answer: A, C. Use an interconnect VPLS switch; Use a point-to-point logical tunnel.

To enable communication between tenant systems without using physical revenue ports on the SRX Series device, you can use an interconnect VPLS switch, which provides Layer 2 connectivity between tenants, or a point-to-point logical tunnel, which creates a dedicated virtual connection path between tenant systems. Both methods avoid the need for physical port consumption while maintaining secure tenant isolation.

Why the other options are wrong

  • B. Secure wire is not a valid Junos networking construct for tenant communication.
  • D. An external router would require physical connections and does not address the requirement of avoiding physical revenue ports.

Question 2

Which two statements are correct about automated threat mitigation with Security Director? (Choose two.)

  1. Infected hosts are tracked by their IP address.
  2. Infected hosts are tracked by their user identity.
  3. Infected hosts are tracked by their chassis serial number.
  4. Infected hosts are tracked by their MAC address.
Show answer and explanation

Correct answer: A, D. Infected hosts are tracked by their IP address; Infected hosts are tracked by their MAC address.

Automated threat mitigation with Security Director tracks infected hosts using two distinct identifiers: their IP address, which identifies the network location of the host, and their MAC address, which identifies the physical network interface. These two tracking methods together provide comprehensive identification of compromised devices for mitigation purposes.

Why the other options are wrong

  • B. User identity is not a primary tracking mechanism for infected hosts in automated threat mitigation; IP and MAC addresses are the standard identifiers.
  • C. Chassis serial number is not used by Security Director for tracking infected hosts in automated threat mitigation scenarios.

Question 3

You have deployed two SRX Series devices in an active/passive multinode HA scenario. In this scenario, which two statements are correct? (Choose two.)

  1. Services redundancy group 0 (SRG0) is used for services that have a control plane state.
  2. Services redundancy group 1 (SRG1) is used for services that have a control plane state.
  3. Services redundancy group 0 (SRG0) is used for services that do not have a control plane state.
  4. Services redundancy group 1 (SRG1) is used for services that do not have a control plane state.
Show answer and explanation

Correct answer: B, C. Services redundancy group 1 (SRG1) is used for services that have a control plane state; Services redundancy group 0 (SRG0) is used for services that do not have a control plane state.

In an active/passive multinode HA scenario on SRX Series devices, Services Redundancy Group 1 (SRG1) is used for services that have control plane state, allowing stateful failover of control plane operations, while Services Redundancy Group 0 (SRG0) is used for services that do not have control plane state, supporting stateless or data plane only services.

Why the other options are wrong

  • A. SRG0 is not used for services with control plane state; it is reserved for stateless services.
  • D. SRG1 is not used for services without control plane state; it is designated for services requiring state preservation.

Question 4

Which two statements are true regarding NAT64? (Choose two.)

  1. An SRX Series device should be in flow-based forwarding mode for IPv4.
  2. An SRX Series device should be in packet-based forwarding mode for IPv4.
  3. An SRX Series device should be in packet-based forwarding mode for IPv6.
  4. An SRX Series device should be in flow-based forwarding mode for IPv6.
Show answer and explanation

Correct answer: A, D. An SRX Series device should be in flow-based forwarding mode for IPv4; An SRX Series device should be in flow-based forwarding mode for IPv6.

For NAT64 functionality on an SRX Series device, the device must operate in flow-based forwarding mode for IPv4 traffic, which enables stateful connection handling, and in flow-based forwarding mode for IPv6 traffic to maintain consistency in bidirectional translation and state tracking across the IPv4-to-IPv6 gateway.

Why the other options are wrong

  • B. Packet-based forwarding mode is not suitable for IPv4 in NAT64; flow-based mode is required for stateful translation.
  • C. Packet-based forwarding mode is not appropriate for IPv6 in NAT64 operations; flow-based forwarding is necessary.

Question 5

You need to set up source NAT so that external hosts can initiate connections to an internal device but only if a connection to the device was first initiated by the internal device. Which type of NAT solution provides this functionality?

  1. persistent NAT with any remote host
  2. static NAT
  3. persistent NAT with target host
  4. address persistent
Show answer and explanation

Correct answer: C. persistent NAT with target host

Persistent NAT with target host provides the functionality where external hosts can initiate return connections only to the specific internal device that first initiated an outbound connection. This approach maintains a persistent mapping between the internal host and the external target host, restricting inbound connections to only those targets involved in the original outbound session.

Question 6

Which two statements are true about the procedures the Junos security device uses when handling traffic destined for the device itself? (Choose two.)

  1. If the received packet is addressed to the ingress interface, then the device first performs a security policy evaluation for the junos-host zone.
  2. If the received packet is addressed to the ingress interface, then the device first examines the host -inbound-traffic configuration for the ingress interface and zone.
  3. If the received packet is destined for an interface other than the ingress interface, then the device performs a security policy evaluation based on the ingress and egress zone.
  4. If the received packet is destined for an interface other than the ingress interface, then the device performs a security policy evaluation for the junos-host zone.
Show answer and explanation

Correct answer: B, C. If the received packet is addressed to the ingress interface, then the device first examines the host -inbound-traffic configuration for the ingress interface and zone; If the received packet is destined for an interface other than the ingress interface, then the device performs a security policy evaluation based on the ingress and egress zone.

When handling traffic destined for the Junos security device itself, if the packet is addressed to the ingress interface, the device examines the host-inbound-traffic configuration for that ingress interface and zone before proceeding. Additionally, if the packet is destined for an interface other than the ingress interface, the device performs security policy evaluation based on the ingress and egress zones involved in the path.

Why the other options are wrong

  • A. When traffic is addressed to the ingress interface, the device checks host-inbound-traffic configuration first, not security policy evaluation for the junos-host zone.
  • D. Packets destined for interfaces other than the ingress interface are evaluated based on ingress and egress zones, not automatically against the junos-host zone.

Question 7

Which two statements are correct about mixed mode? (Choose two.)

  1. IRB interfaces cannot be used to route traffic.
  2. Layer 2 and Layer 3 interfaces can use separate security zones.
  3. IRB interfaces can be used to route traffic.
  4. Layer 2 and Layer 3 interfaces can use the same security zone.
Show answer and explanation

Correct answer: C, D. IRB interfaces can be used to route traffic; Layer 2 and Layer 3 interfaces can use the same security zone.

In mixed mode on SRX Series devices, IRB (Integrated Routing and Bridging) interfaces can be used to route traffic between Layer 2 and Layer 3 domains. Additionally, Layer 2 and Layer 3 interfaces can share the same security zone, allowing flexible network segmentation while maintaining unified security policies across bridged and routed traffic.

Why the other options are wrong

  • A. IRB interfaces are specifically designed to enable routing functionality in mixed mode environments.
  • B. Layer 2 and Layer 3 interfaces in mixed mode can use the same security zone, not separate ones.

Question 8

You are asked to configure tenant systems. Which two statements are true in this scenario? (Choose two.)

  1. Tenant systems have their own configuration database.
  2. A tenant system can have only one administrator.
  3. You can commit multiple tenant systems at a time.
  4. After successful configuration, the changes are merged into the primary database for each tenant system.
Show answer and explanation

Correct answer: A, C. Tenant systems have their own configuration database; You can commit multiple tenant systems at a time.

Tenant systems each maintain their own independent configuration database, allowing isolated configuration management per tenant. Additionally, you can commit multiple tenant systems at a time, enabling batch configuration updates across several tenants in a single operation, which improves administrative efficiency in multi-tenant deployments.

Why the other options are wrong

  • B. A tenant system can have multiple administrators assigned with different privilege levels and responsibilities.
  • D. Tenant system configurations are committed directly to each tenant's own database; they are not merged into a shared primary database.

Question 9

In a multimode HA environment, which service must be configured to synchronize between nodes?

  1. PKI certificated
  2. IDP
  3. IPsec VPN
  4. advanced policy-based routing
Show answer and explanation

Correct answer: B. IDP

In a multimode HA environment, the Identity Provider (IDP) service must be synchronized between nodes to ensure consistent threat detection and security policy enforcement across the HA pair. IDP maintains session state and threat intelligence that requires synchronization for proper failover behavior.

Why the other options are wrong

  • A. PKI certificates are not the primary synchronization service in HA environments; certificate distribution is handled separately.
  • C. IPsec VPN tunnels are traffic-bearing services but not the core synchronization mechanism for HA node coordination.
  • D. Advanced policy-based routing is a traffic forwarding feature, not a synchronization service.

Question 10

You are deploying threat remediation to endpoints connected through third-party devices. In this scenario, which three statements are correct? (Choose three.)

  1. All third-party switches must support AAA/RADIUS and Dynamic Authorization Extensions to the RADIUS protocol.
  2. The connector uses an API to gather endpoint MAC address information from the RADIUS server.
  3. All third-party switches in the specified network are automatically mapped and registered with the RADIUS server.
  4. The connector queries the RADIUS server for the infected host endpoint details and initiates a change of authorization (CoA) for the infected host.
  5. The RADUIS server sends Status-Server messages to update infected host information to the connector.
Show answer and explanation

Correct answer: A, B, D. All third-party switches must support AAA/RADIUS and Dynamic Authorization Extensions to the RADIUS protocol; The connector uses an API to gather endpoint MAC address information from the RADIUS server; The connector queries the RADIUS server for the infected host endpoint details and initiates a change of authorization (CoA) for the infected host.

When deploying threat remediation through third-party devices, third-party switches must support AAA/RADIUS and Dynamic Authorization Extensions (DAE) to enable CoA functionality. The connector queries the RADIUS server for infected host details and initiates a Change of Authorization (CoA) to the infected endpoint. The connector uses RADIUS server queries to gather endpoint MAC address information for targeting. These three mechanisms work together to identify and isolate threats at the network edge.

Why the other options are wrong

  • C. Third-party switches are not automatically mapped and registered; they must be explicitly configured and integrated with the RADIUS infrastructure.
  • E. The RADIUS server does not send Status-Server messages to update infected host information; the connector actively queries the server and initiates CoA commands.

What people say about the full JN0-637 pack 5.0 from 1

Your questions for JN0-637 exam are still valid! Thanks a lot!
Jefferey BascombJN0-637

Question 11

You want to test how the device handles a theoretical session without generating traffic on the Junos security device. Which command is used in this scenario?

  1. show security policies
  2. request security policies check
  3. show security match-policies
  4. show security flow session
Show answer and explanation

Correct answer: C. show security match-policies

The 'show security match-policies' command allows testing how the device would handle a theoretical session by matching traffic criteria against configured security policies without generating actual traffic. This command simulates policy evaluation for diagnostic purposes.

Why the other options are wrong

  • A. The 'show security policies' command displays policy configuration but does not perform matching or simulation.
  • B. The 'request security policies check' command validates policy syntax but does not simulate session handling.
  • D. The 'show security flow session' command displays active sessions, requiring actual traffic to exist.

Question 12

Your IPsec tunnel is configured with multiple security associations (SAs). Your SRX Series devices supports the CoS-based IPsec VPNs with multiple IPsec SAs feature. You are asked to configure CoS for this tunnel. Which two statements are true in this scenario? (Choose two.)

  1. A maximum of four forwarding classes can be configured for a VPN with the multi-sa forwarding-classes statement.
  2. The local and remote gateways do not need the forwarding classes to be defined in the same order.
  3. A maximum of eight forwarding classes can be configured for a VPN with the –multi-sa forwarding-classes– statement.
  4. The local and remote gateways must have the forwarding classes defined in the same order.
Show answer and explanation

Correct answer: C, D. A maximum of eight forwarding classes can be configured for a VPN with the –multi-sa forwarding-classes– statement; The local and remote gateways must have the forwarding classes defined in the same order.

When configuring CoS for IPsec tunnels with multiple SAs, a maximum of eight forwarding classes can be configured for a VPN using the multi-sa forwarding-classes statement. Additionally, the local and remote gateways must have the forwarding classes defined in the same order to ensure consistent traffic classification and handling across the tunnel endpoints.

Why the other options are wrong

  • A. The maximum is eight forwarding classes, not four.
  • B. The local and remote gateways must have matching forwarding class definitions in the same order for proper operation.

Question 13

Your customer needs embedded security in an EVPN-VXLAN solution. What are two benefits of adding an SRX Series device in this scenario? (Choose two.)

  1. It enhances tunnel inspection for VXLAN encapsulated traffic with Layer 4-7 security services.
  2. It adds extra security with the capabilities of an enterprise grade firewall in the EVPN-VXLAN underlay.
  3. It adds extra security with the capabilities of an enterprise grade firewall in the EVPN-VXLAN overlay.
  4. It enhances tunnel inspection for VXLAN encapsulated traffic with only Layer 4 security services.
Show answer and explanation

Correct answer: A, C. It enhances tunnel inspection for VXLAN encapsulated traffic with Layer 4-7 security services; It adds extra security with the capabilities of an enterprise grade firewall in the EVPN-VXLAN overlay.

Adding an SRX Series device to an EVPN-VXLAN solution provides two key benefits: it enhances tunnel inspection for VXLAN-encapsulated traffic with comprehensive Layer 4-7 security services including deep packet inspection and threat prevention, and it adds enterprise-grade firewall capabilities to the overlay network where east-west traffic between tenants and services is protected. The SRX can inspect VXLAN encapsulated traffic and apply advanced security policies at the application layer within the overlay network.

Why the other options are wrong

  • B. The SRX provides security in the overlay, not the underlay; the underlay is the physical network infrastructure.
  • D. SRX provides comprehensive Layer 4-7 security services, not only Layer 4; this includes application-level inspection and threat prevention.

Question 14

You are deploying a large scale VPN spanning six sites. You need to choose a VPN technology that satisfies the following requirements: all sites must have secure reachability to all other sites. new spoke sites can be added without explicit configuration on the hub site. all spoke-to-spoke communication must traverse the hub site. Which VPN technology will satisfy these requirements?

  1. ADVPN
  2. AutoVPN
  3. secure connect VPN
  4. group VPN
Show answer and explanation

Correct answer: B. AutoVPN

AutoVPN is designed for hub-and-spoke VPN deployments at scale, where new spoke sites can be added dynamically without explicit hub-side reconfiguration. All spokes maintain secure reachability through automatic tunnel establishment, and spoke-to-spoke traffic naturally traverses the hub by architecture. AutoVPN provides centralized management while enabling rapid site onboarding.

Why the other options are wrong

  • A. ADVPN enables dynamic peer discovery and direct spoke-to-spoke communication, which violates the requirement that all traffic traverse the hub.
  • C. Secure connect VPN is a managed service offering, not a VPN technology that addresses these specific topology requirements.
  • D. Group VPN is a legacy technology that does not support dynamic spoke addition without hub reconfiguration.

Question 15

You have deployed an SRX Series device at your network edge to secure Internet-bound sessions for your local hosts using source NAT. You want to ensure that your users are able to interact with applications on the Internet that require more than one TCP session for the same application session. Which two features would satisfy this requirement? (Choose two.)

  1. persistent NAT
  2. address persistence
  3. STUN
  4. double NAT
Show answer and explanation

Correct answer: A, B. persistent NAT; address persistence

Persistent NAT and address persistence are both features that maintain consistent NAT bindings across multiple TCP sessions from the same application. Persistent NAT ensures that all sessions from the same source are translated to the same address, while address persistence maintains the NAT binding state across sessions. These features are essential for applications like FTP that require control and data connections. STUN is used for NAT traversal in peer-to-peer scenarios, not for maintaining application sessions. Double NAT is not a feature that addresses this requirement.

Why the other options are wrong

  • C. STUN is a protocol for NAT traversal in peer-to-peer communications, not for maintaining multi-session application compatibility.
  • D. Double NAT is not a feature that ensures users can interact with multi-session applications.

Question 16

You have deployed automated threat mitigation using Security Director with Policy Enforcer, Juniper ATP Cloud, SRX Series devices, and EX Series switches. In this scenario, which device is responsible for blocking the infected hosts?

  1. EX Series switch
  2. Juniper ATP Cloud
  3. Policy Enforcer
  4. Security Director
Show answer and explanation

Correct answer: A. EX Series switch

The EX Series switch is responsible for blocking infected hosts in the automated threat mitigation workflow. When Policy Enforcer detects a threat via Juniper ATP Cloud and Security Director orchestrates the response, the EX Series switch executes the actual blocking by isolating the infected endpoint through VLAN assignment or port disabling via Dynamic Authorization Extensions.

Why the other options are wrong

  • B. Juniper ATP Cloud identifies threats but does not directly block hosts.
  • C. Policy Enforcer enforces policies but the switch performs the physical isolation.
  • D. Security Director orchestrates the mitigation workflow but does not perform the actual blocking.

Question 17

How does an SRX Series device examine exception traffic?

  1. The device examines the host-outbound traffic for the ingress interface and zone.
  2. The device examines the host-inbound traffic for the ingress interface and zone.
  3. The device examines the host-outbound traffic for the egress interface and zone.
  4. The device examines the host-inbound traffic for the egress interface and zone.
Show answer and explanation

Correct answer: B. The device examines the host-inbound traffic for the ingress interface and zone.

When an SRX Series device examines exception traffic, it evaluates the host-inbound traffic for the ingress interface and zone. Exception traffic refers to traffic destined for the SRX itself or traffic that requires special handling. The examination occurs on inbound traffic at the point of entry to determine how to process it.

Why the other options are wrong

  • A. Exception traffic is examined on inbound traffic, not outbound traffic.
  • C. Exception traffic examination occurs at the ingress interface, not the egress interface.
  • D. While examined at ingress, it is inbound traffic, not outbound, and at the ingress interface, not egress.

Question 18

You are configuring an interconnect logical system that is configured as a VPLS switch to allow two logical systems to communicate. Which two parameters are required when configuring the logical tunnel interfaces? (Choose two.)

  1. The virtual tunnel interfaces should only be configured with two logical unit pairs per logical system interconnect.
  2. The logical tunnel interfaces should be configured with two logical unit pairs per logical system interconnect.
  3. Encapsulation ethernet must be used.
  4. Encapsulation ethernet-vpls must be used.
Show answer and explanation

Correct answer: B, D. The logical tunnel interfaces should be configured with two logical unit pairs per logical system interconnect; Encapsulation ethernet-vpls must be used.

When configuring logical tunnel interfaces for an interconnect logical system operating as a VPLS switch, two logical unit pairs per logical system interconnect are required to establish bidirectional communication. The encapsulation must be set to ethernet-vpls to properly encapsulate frames for VPLS operation across the tunnel. The ethernet-vpls encapsulation type is specifically designed for VPLS service operation, enabling proper layer 2 bridging between logical systems.

Why the other options are wrong

  • A. The requirement is not to limit to two logical unit pairs; rather, exactly two are needed for proper VPLS interconnect operation.
  • C. Plain ethernet encapsulation is insufficient; ethernet-vpls encapsulation is required for VPLS service operation.

Question 19

What are three core components for enabling advanced policy-based routing? (Choose three.)

  1. APBR profile
  2. routing instance
  3. filter-based forwarding
  4. policies
  5. routing options
Show answer and explanation

Correct answer: A, B, D. APBR profile; routing instance; policies

Advanced Policy-Based Routing (APBR) requires three core components: an APBR profile that defines the routing policy parameters, a routing instance that provides the forwarding context for policy-based decisions, and policies that specify the routing rules based on traffic characteristics. These three components work together to enable sophisticated routing decisions beyond standard destination-based routing. Routing options and filter-based forwarding are supporting features but not core components of APBR.

Why the other options are wrong

  • C. Filter-based forwarding is a related feature but not a core component of APBR configuration.
  • E. Routing options are general configuration parameters but not a core component specifically required for APBR.

Question 20

You are asked to see if your persistent NAT binding table is exhausted. Which show command would you use to accomplish this task?

  1. show security nat source persistent-nat-table summary
  2. show security nat source persistent-nat-table all
  3. show security nat source pool all
  4. show security nat source summary
Show answer and explanation

Correct answer: A. show security nat source persistent-nat-table summary

The command 'show security nat source persistent-nat-table summary' displays a summary of the persistent NAT binding table, including utilization statistics and exhaustion status. This command provides the information needed to determine if the binding table is depleted or approaching capacity.

Why the other options are wrong

  • B. The 'all' option displays detailed bindings rather than summary exhaustion information.
  • C. The pool command shows NAT pool configuration and availability, not persistent binding table status.
  • D. The generic summary command does not provide persistent NAT table specific information.

Question 21

You are attempting to ping an interface on your SRX Series device, but the ping is unsuccessful. What are three reasons for this behavior? (Choose three.)

  1. The interface is not assigned to a security zone.
  2. The interface’s host-inbound-traffic security zone configuration does not permit ping.
  3. The ping traffic is matching a firewall filter.
  4. The device has J-Web enabled.
  5. The interface has multiple logical units configured.
Show answer and explanation

Correct answer: A, B, C. The interface is not assigned to a security zone; The interface’s host-inbound-traffic security zone configuration does not permit ping; The ping traffic is matching a firewall filter.

Ping traffic can fail if the interface lacks security zone assignment, preventing policy evaluation. If assigned to a zone, the zone's host-inbound-traffic configuration must explicitly permit ICMP for ping to succeed. Additionally, firewall filters applied to the interface can match and deny ping traffic before it reaches the routing engine.

Why the other options are wrong

  • D. J-Web enablement is a management interface feature that does not affect data plane ping traffic.
  • E. Multiple logical units on an interface do not inherently prevent ping; each logical unit operates independently with its own configuration.

Question 22

You configure two Ethernet interfaces on your SRX Series device as Layer 2 interfaces and add them to the same VLAN. The SRx is using the default 12-learning setting. You do not add the interfaces to a security zone. Which two statements are true in this scenario? (Choose two.)

  1. You cannot add Layer 2 interfaces to a security zone.
  2. You are unable to apply stateful security features to traffic that is switched between the two interfaces.
  3. The interfaces will not forward traffic by default.
  4. You are able to apply stateful security features to traffic that enters and exits the VLAN.
Show answer and explanation

Correct answer: B, C. You are unable to apply stateful security features to traffic that is switched between the two interfaces; The interfaces will not forward traffic by default.

When Layer 2 interfaces are configured in a VLAN without assignment to a security zone, the interfaces will not forward traffic by default as there is no security policy to permit traffic flow. Additionally, without being in a security zone, stateful security features cannot be applied to traffic switched between these Layer 2 interfaces, as security policies operate at the zone level.

Why the other options are wrong

  • A. Layer 2 interfaces can be added to security zones for policy application.
  • D. Stateful security features cannot be applied to Layer 2 VLAN traffic without the interfaces being in a security zone.

Question 23

You are enabling advanced policy-based routing. You have configured a static route that has a next hop from the inet0 routing table. Unfortunately, this static route is not active in your routing instance. In this scenario, which solution is needed to use this next hop?

  1. Use filter-based forwarding.
  2. Use policies.
  3. Use RIB groups.
  4. Use transparent mode.
Show answer and explanation

Correct answer: C. Use RIB groups.

When configuring advanced policy-based routing with a static route that has a next hop from the inet0 routing table but is not active in the routing instance, RIB groups (Routing Information Base groups) are needed to enable communication between different routing tables and instances. RIB groups allow the next hop from inet0 to be available and usable within the active routing instance.

Why the other options are wrong

  • A. Filter-based forwarding is used for packet filtering decisions but does not resolve routing table availability issues.
  • B. Policies alone do not enable cross-routing-table lookups; RIB groups are required for this functionality.
  • D. Transparent mode is unrelated to policy-based routing or routing instance configuration.

Question 24

You are asked to create multiple virtual routers using a single SRX Series device. You must ensure that each virtual router maintains a unique copy of the routing protocol daemon (RPD) process. Which solution will accomplish this task?

  1. tenant system
  2. secure wire
  3. transparent mode
  4. logical system
Show answer and explanation

Correct answer: D. logical system

Logical systems enable the creation of multiple virtual routers on a single SRX Series device, with each logical system maintaining its own independent routing protocol daemon (RPD) process. This architecture allows complete separation of routing domains and protocol instances across a single physical device.

Why the other options are wrong

  • A. Tenant system is used for multi-tenancy in data center contexts, not for creating independent RPD processes.
  • B. Secure wire is a feature for secure inter-zone communication, not for creating virtual routers.
  • C. Transparent mode changes the device forwarding model but does not create independent routing protocol instances.

Question 25

Which role does an SRX Series device play in a DS-Lite deployment?

  1. softwire concentrator
  2. softwire initiator
  3. STUN client
  4. STUN server
Show answer and explanation

Correct answer: A. softwire concentrator

In a DS-Lite (Dual-Stack Lite) deployment, the SRX Series device functions as a softwire concentrator. The softwire concentrator is the AFTR (Address Family Transition Router) that receives IPv6-encapsulated IPv4 traffic from softwire initiators (customer devices) and de-encapsulates it for routing to the IPv4 Internet. This concentrator function is the primary role of the SRX in DS-Lite architecture.

Why the other options are wrong

  • B. Softwire initiator is the role of customer devices, not the SRX concentrator.
  • C. STUN client functionality is not part of DS-Lite concentrator responsibilities.
  • D. STUN server is not related to DS-Lite deployment architecture.

25 questions in. Want the rest? The first half of the pack, free by email · The full pack

Question 26

You have deployed automated threat mitigation using Security Director with Policy Enforcer, Juniper ATP Cloud, SRX Series devices, Forescout, and third-party switches. In this scenario, which device is responsible for communicating directly to the third-party switches when infected hosts need to be blocked?

  1. Forescout
  2. Juniper ATP cloud
  3. SRX Series device
  4. Policy Enforcer
Show answer and explanation

Correct answer: A. Forescout

Forescout is a network access control (NAC) platform that discovers and identifies devices on the network, including infected hosts. In an automated threat mitigation workflow, Forescout communicates directly with third-party network switches to enforce containment policies by isolating or blocking infected hosts at the network access layer. While Security Director, Policy Enforcer, and SRX devices manage policies and threat response, Forescout serves as the bridge between threat detection and direct switch-level remediation.

Why the other options are wrong

  • B. Juniper ATP Cloud provides threat intelligence and detection but does not directly interface with third-party switches.
  • C. SRX Series devices enforce policies but do not directly communicate with third-party switches for host isolation.
  • D. Policy Enforcer manages policy distribution from Security Director but is not responsible for direct switch communication.

That was 26 of 103.

The full Juniper JN0-637 JNCIP-SEC pack has all 103 questions, each with the answer, the explanation and why the other options are wrong, plus a questions-only copy for timed runs. US$39, paid once, with free monthly updates and a pass-or-your-money-back guarantee.

Get the full pack

Not ready yet? Get the first 52 free as one PDF by email. Get the Half Pack →