Juniper Juniper Certifications JN0-637 Questions & Answers

• Question 41:

  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 L2-learning setting. You do not add the interfaces to a security zone.

  Which two statements are true in this scenario? (Choose two.)

  A. You are unable to apply stateful security features to traffic that is switched between the two interfaces.

  B. You are able to apply stateful security features to traffic that enters and exits the VLAN.

  C. The interfaces will not forward traffic by default.

  D. You cannot add Layer 2 interfaces to a security zone.

  Correct Answer: AC

  When Ethernet interfaces are configured as Layer 2 and added to the same VLAN without being assigned to a security zone, they will not forward traffic by default. Additionally, because they are operating in a pure Layer 2 switching mode,

  they lack the capability to enforce stateful security policies. For further details, refer to Juniper Ethernet Switching Layer 2 Documentation.

  of Answer A (Unable to Apply Stateful Security Features):

  When two interfaces are configured as Layer 2 interfaces and belong to the same VLAN but are not assigned to any security zone, traffic switched between them is handled purely at Layer 2. Stateful security features , such as firewall

  policies, are applied at Layer 3, so traffic between these interfaces will not undergo any stateful inspection or firewalling by default.

  of Answer C (Interfaces Will Not Forward Traffic):

  In Junos, Layer 2 interfaces must be added to a security zone to allow traffic forwarding. Since the interfaces in this scenario are not part of a security zone, they will not forward traffic by default until assigned to a zone. This is a security

  measure to prevent unintended forwarding of traffic.

  Juniper Security Reference:

  Layer 2 Interface Configuration: Layer 2 interfaces must be properly assigned to security zones to enable traffic forwarding and apply security policies. Reference: Juniper Networks Layer 2 Interface Documentation.

• Question 42:

  Referring to the exhibit.

  

  What do you use to dynamically secure traffic between the Azure and AWS clouds?

  A. You can dynamically secure traffic between the clouds by using user identities in the security policies.

  B. You can dynamically secure traffic between the clouds by using advanced connection tracking in the security policies.

  C. You can dynamically secure traffic between the clouds by using security tags in the security policies.

  D. You can dynamically secure traffic between the clouds by using URL filtering in the security policies.

  Correct Answer: C

  Security tags facilitate dynamic traffic management between cloud environments like Azure and AWS. Tags allow flexible policies that respond to cloud-native events or resource changes, ensuring secure inter-cloud communication. For more

  information, see Juniper Cloud Security Tags.

  In the scenario depicted in the exhibit, where traffic needs to be dynamically secured between Azure and AWS clouds, the best method to achieve dynamic security is by using security tags in the security policies.

  of Answer C (Security Tags in Security Policies):

  Security tagsallow dynamic enforcement of security policies based on metadata rather than static IP addresses or zones. This is crucial in cloud environments, where resources and IP addresses can change dynamically. Using security tags

  in the security policies, you can associate traffic flows with specific applications, services, or virtual machines, regardless of their underlying IP addresses or network locations. This ensures that security policies are automatically updated as

  cloud resources change.

  Juniper Security Reference:

  Dynamic Security with Security Tags: This feature allows you to dynamically secure cloud-based traffic using metadata and tags, ensuring that security policies remain effective even in dynamic environments. Reference: Juniper Security

  Tags Documentation.

• Question 43:

  You have an initial setup of ADVPN with two spokes and a hub. A host at partner Spoke-1 is sending traffic to a host at partner Spoke-2.

  In this scenario, which statement is true?

  A. Spoke-1 will establish a VPN to Spoke-2 when this is first deployed, so traffic will be sent immediately to Spoke-2.

  B. Spoke-1 will send the traffic through the hub and not use a direct VPN to Spoke-2.

  C. Spoke-1 will establish the tunnel to Spoke-2 before sending any of the host traffic.

  D. Spoke-1 will send the traffic destined to Spoke-2 through the hub until the VPN is established between the spokes.

  Correct Answer: D

  In an ADVPN (Auto-Discovery VPN) environment with a hub-and-spoke topology, the initial communication between two spokes (Spoke-1 and Spoke-2) is always routed through the hub. Once the hub detects the communication, it facilitates the creation of a direct VPN tunnel between the spokes. Until this dynamic tunnel is established, the traffic between the spokes continues to pass through the hub.

  In this scenario, Spoke-1 will route traffic through the hub initially until the direct VPN tunnel to Spoke-2 is established.

• Question 44:

  Referring to the exhibit.

  

  

  Referring to the exhibit, which two statements are correct? (Choose two.)

  A. The ge-0/0/3.0 and ge-0/0/4.0 interfaces are not active and will not respond to ARP requests to the virtual IP MAC address.

  B. This device is the backup node for SRG1.

  C. The ge-0/0/3.0 and ge-0/0/4.0 interfaces are active and will respond to ARP requests to the virtual IP MAC address.

  D. This device is the active node for SRG1.

  Correct Answer: AB

  The interfaces are active and respond to ARP for virtual IP as long as the node is the primary or active node in the SRG group. This ensures high availability and proper traffic forwarding. For information, refer to Juniper SRX HA

  Documentation.

  The exhibit shows information about a chassis cluster and its services redundancy group (SRG1) . Let's analyze the relevant details:

  of Answer B (Backup Node for SRG1):

  The exhibit indicates that this SRX device is in the backup role for SRG1. The status: BACKUP field confirms that this device is currently in a standby role and is not the active node for the services redundancy group.

  of Answer A (Interfaces Not Active):

  Since the device is in the backup role, the interfaces ge-0/0/3.0 and ge-0/0/4.0 will not respond to ARP requests for the virtual IP's MAC address. Only the active node's interfaces respond to ARP requests in a chassis cluster configuration.

  Juniper Security Reference:

  Chassis Cluster Redundancy Overview: In a chassis cluster, the backup node does not respond to ARP requests for the virtual IP. Only the active node handles such requests to ensure seamless traffic forwarding. Reference: Juniper Chassis

  Cluster Documentation.

• Question 45:

  You are asked to establish a hub-and-spoke IPsec VPN using an SRX Series device as the hub. All of the spoke devices are third-party devices.

  Which statement is correct in this scenario?

  A. You must ensure that you are using aggressive mode when incorporating third-party devices as your spokes.

  B. You must statically configure the next-hop tunnel binding table entries for each of the third-party spoke devices.

  C. You must create a policy-based VPN on the hub device when peering with third-party devices.

  D. You must always peer using loopback addresses when using non-Junos devices as your spokes.

  Correct Answer: B

  To ensure compatibility with third-party devices, next-hop tunnel binding must be manually configured, as dynamic protocols may not be universally supported. This ensures proper routing and secure connections. See Juniper IPsec VPN

  Configuration Guide.

  In a hub-and-spoke IPsec VPN configuration where an SRX device serves as the hub and the spokes are third- party devices, special considerations must be taken into account due to the variability in VPN implementations across different

  vendors.

  Next-Hop Tunnel Binding (Correct: Option B):With third-party devices as spokes, dynamic routing protocols (like NHRP) may not be supported for dynamically learning spoke routes. In such cases, the next-hop tunnel binding table must be

  statically configured for each spoke on the SRX hub to ensure proper routing and VPN communication. This ensures that traffic between the spokes is routed correctly through the hub.

  Incorrect Options:

  Option Ais incorrect because aggressive mode is typically less secure and not recommended for hub-and-spoke topologies, especially with third-party devices. Option Cis incorrect because a route-based VPN is usually preferred when

  peering with third- party devices for flexibility and scalability. Option Dis incorrect because using loopback addresses is not a requirement when peering with third-party devices. It is a common practice in certain designs, but it is not

  mandatory.

  Juniper References:

  Juniper IPsec VPN Configuration Guide: Provides insights on hub-and-spoke VPN configurations, including next-hop tunnel binding and considerations when working with third-party devices.

• Question 46:

  Referring to the exhibit, which two statements are correct about the NAT configuration? (Choose two.)

  

  A. Both the internal and the external host can initiate a session after the initial translation.

  B. Only a specific host can initiate a session to the reflexive address after the initial session.

  C. Any external host will be able to initiate a session to the reflexive address.

  D. The original destination port is used for the source port for the session.

  Correct Answer: BD

  The NAT setup allows only specific external hosts to reach the internal network post-initial session, providing controlled access. Reflexive NAT preserves the source port from the original request, maintaining continuity. More on this can be

  found in Juniper NAT Configuration Documentation. Looking at the NAT configuration, we observe the use of persistent NAT with the keyword permit target-host . Here's a detailed breakdown:

  Persistent NAT (Correct: Option B):When persistent NAT is configured with the permit target-host option, it allows the internal host (from the 172.16.1.0/24 network) to initiate communication with an external host. After the initial session is

  established, only the specific external host (target host) is allowed to initiate subsequent sessions to the internal host using the reflexive address. This ensures that random external hosts cannot initiate sessions, which enhances security.

  Original Destination Port Reuse (Correct: Option D):In this configuration, theinterface-based source NAT uses the original destination port of the incoming session as the source port for the outbound session. This maintains port transparency

  for NATed traffic, which can be crucial for certain types of applications that depend on consistent port numbers.

  Incorrect Options:

  Option Ais incorrect because persistent NAT with target-host does not allow both internal and external hosts to initiate sessions freely. Only the specific external hostcan initiate a session after the initial session is established by the internal

  host.

  Option Cis incorrect because only the specific external host can initiate subsequent sessions, not any random external host.

  Juniper References:

  Juniper NAT Documentation: Describes the behavior of persistent NAT and how target-host restrictions work for enhanced security.

• Question 47:

  Referring to the exhibit.

  

  

  In which mode is the SRX Series device?

  A. Packet

  B. Ethernet switching

  C. Mixed

  D. Transparent

  Correct Answer: D

  The exhibit shows that the Global Mode of the SRX Series device is set to "Transparent bridge." This means the device is operating in transparent mode . In this mode, the SRX Series device acts like a Layer 2 bridge, forwarding traffic based

  on MAC addresses and not performing any Layer 3 (IP) routing or firewalling.

  In transparent mode , the SRX device is effectively invisible to the network at the IP layer, and it bridges traffic between Ethernet interfaces without needing to assign IP addresses to those interfaces. This mode is typically used when you

  want the SRX to act as a firewall without making any changes to the network's routing configuration.

  Key Indicators from the Exhibit:

  Global Mode: Transparent bridge: This confirms that the device is configured in transparent mode.

  MAC learningand Ethernet Switching options are enabled, which aligns with transparent mode functionality where the device learns MAC addresses and switches traffic between VLANs.

  Juniper Security Reference:

  Transparent Mode Overview: Transparent mode is used to deploy a firewall in Layer 2 mode, where it bridges traffic between VLANs without being an IP routing device. Reference: Juniper Networks Transparent Mode Documentation.

• Question 48:

  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?

  A. Secure wire

  B. Tenant system

  C. Transparent mode

  D. Logical system

  Correct Answer: D

  Logical systems on SRX Series devices allow the creation of separate virtual routers, each with its unique RPD process. This segmentation ensures that routing and security policies are isolated across different logical systems, effectively

  acting like independent routers within a single SRX device. For further information, see Juniper Logical Systems Documentation.

  To create multiple virtual routers on a single SRX Series device, each with its own unique copy of the routing protocol daemon (RPD) process, you need to use logical systems . Logical systems allow for the segmentation of an SRX device

  into multiple virtual routers, each with independent configurations, including routing instances, policies, and protocol daemons.

  of Answer D (Logical System):

  A logical system on an SRX device enables you to create multiple virtual instances of the SRX, each operating independently with its own control plane and routing processes. Each logical system gets a separate copy of the RPD process,

  ensuring complete isolation between virtual routers.

  This is the correct solution when you need separate routing instances with their own RPD processes on the same physical device.

  Configuration Example:

  bash

  Copy code

  set logical-systems interfaces ge-0/0/0 unit 0

  set logical-systems routing-options static route 0.0.0.0/0 next-hop 192.168.1.1

  Juniper Security Reference:

  Logical Systems Overview: Logical systems allow for the creation of multiple virtual instances within a single SRX device, each with its own configuration and control plane. Reference: Juniper Logical Systems Documentation.

• Question 49:

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

  A. Infected hosts are tracked by their IP address.

  B. Infected hosts are tracked by their chassis serial number.

  C. Infected hosts are tracked by their MAC address.

  D. Infected hosts are tracked by their user identity.

  Correct Answer: AD

  Security Director provides an integrated security management solution for Juniper devices, including SRX Series Firewalls. Automated threat mitigation refers to the system's capability to react dynamically to security incidents such as

  malware infections, based on predefined policies. Let's dive into the details behind each selected option:

  IP Address Tracking (Correct: Option A):Infected hosts are tracked by their IP address because the firewall and threat mitigation systems use the IP address as a key identifier for network traffic and routing. IP addresses are fundamental in

  identifying which device on the network is exhibiting malicious behavior. Security Director can automatically track and block these infected hosts using their IP addresses by correlating threat logs and incident data with a specific device's

  network activities.

  User Identity Tracking (Correct: Option D):Security Director integrates with identity management solutions and LDAP directories to correlate security incidents with specific user identities. This capability allows the security system to track

  threats not only by device but also by the authenticated user currently associated with that device. This feature is particularly useful in environments where multiple users share devices, or where network access is granted based on user

  credentials.

  Now, let's discuss why the other options are incorrect:

  MAC Address Tracking (Incorrect: Option C):While MAC addresses can be used for identifying devices on the same local network, they are not a primary tracking method for infected hosts in the broader network managed by Security

  Director. MAC addresses are not visible once traffic passes through routers since Layer 2 information is stripped off. Therefore, Juniper's automated threat mitigation focuses more on IP and user identity tracking rather than MAC addresses.

  Chassis Serial Number Tracking (Incorrect: Option B):Tracking infected hosts by chassis serial number is not a common practice in automated threat mitigation. Serial numbers are primarily used for inventory and hardware management

  purposes, rather than for identifying infected hosts or mitigating threats in real time.

  Juniper References:

  Juniper Security Director Documentation explains how IP addresses and user identities are tracked for threat mitigation, highlighting the importance of dynamic response based on these identifiers. Security Director supports dynamic

  blocklists and real-time mitigation strategies based on both IP and user-based tracking, leveraging integration with Active Directory (AD) or LDAP for identity-based policies.

• Question 50:

  You want to deploy two vSRX instances in different public cloud providers to provide redundant security services for your network. Layer 2 connectivity between the two vSRX instances is not possible.

  What would you configure on the vSRX instances to accomplish this task?

  A. Chassis cluster

  B. Secure wire

  C. Multinode HA

  D. Virtual chassis

  Correct Answer: B

  In this scenario, you are deploying two vSRX instances across different public cloud providers. Since Layer 2 connectivity is not possible between the two instances, traditional chassis clustering (which requires L2) will not work. Instead, you

  can use Secure Wire to connect the two vSRX instances, ensuring that traffic flows between them securely without Layer 2 requirements.

  of Answer B (Secure Wire):

  Secure Wireis a feature in Junos that allows two interfaces on the SRX to act as a Layer 2 wire, passing traffic transparently between them. However, traffic passing through the secure wire is still subject to security policies, which allows you

  to apply firewall rules without performing routing or switching.

  This solution fits the requirement to have security services between the vSRX instances in different cloud environments without needing L2 connectivity.

  Juniper Security Reference:

  Secure Wire Overview: Secure Wire allows traffic to pass transparently while still applying security services, which is ideal for situations where Layer 2 connectivity is not possible. Reference: Juniper Secure Wire Documentation.