JN0-637 Exam Questions and Answers | Exam-Dumps (Page: 4)

QUESTION: 16

You are asked to connect two hosts that are directly connected to an SRX Series device. The traffic should flow unchanged as it passes through the SRX, and routing or switch lookups should not be performed. However, the traffic should still be subjected to security policy checks.
What will provide this functionality?

MACsec
Mixed mode
Secure wire
Transparent mode

Answer(s): C

Explanation:

Secure wire mode on SRX devices allows traffic to flow transparently through the firewall without being routed or switched, while still applying security policies. This is ideal for scenarios where traffic inspection is required without altering the traffic path or performing additional routing decisions. For further details on Secure Wire, refer to Juniper Secure Wire Documentation.

In this scenario, you want traffic to pass through the SRX unchanged (without routing or switching lookups) but still be subject to security policy checks. The best solution for this requirement is Secure

Wire.
Explanation of Answer C (Secure Wire):
Secure Wire allows traffic to flow through the SRX without any Layer 3 routing or Layer 2 switching decisions. It effectively bridges two interfaces at Layer 2 while still applying security policies. This ensures that traffic remains unchanged, while security policies (such as firewall rules) can still be enforced.
This is an ideal solution when you need the SRX to act as a "bump in the wire" for security enforcement without changing the traffic or performing complex network lookups.
Juniper Security

Reference:

Secure Wire Functionality: Provides transparent Layer 2 forwarding with security policy enforcement, making it perfect for scenarios where traffic needs to pass through unchanged.

Juniper Secure Wire Documentation.

Reveal Solution Next Question

QUESTION: 17

Which two statements are true when setting up an SRX Series device to operate in mixed mode? (Choose two.)

A physical interface can be configured to be both a Layer 2 and a Layer 3 interface at the same time.
User logical systems support Layer 2 traffic processing.
The SRX must be rebooted after configuring at least one Layer 3 and one Layer 2 interface.
Packets from Layer 2 interfaces are switched within the same bridge domain.

Answer(s): C,D

Explanation:

In mixed mode, SRX devices can simultaneously handle Layer 2 switching and Layer 3 routing, but a reboot is required when configuring Layer 2 and Layer 3 interfaces to ensure the configuration takes effect. Layer 2 packets are switched within the defined bridge domain. Further guidance on SRX mixed mode can be found at Juniper Mixed Mode Documentation.

When an SRX Series device is configured in mixed mode, both Layer 2 switching and Layer 3 routing functionalities can be used on the same device. This enables the SRX to act as both a router and a switch for different interfaces. However, there are certain considerations:

Explanation of Answer C (Reboot Requirement):
After configuring the SRX to operate with at least one Layer 2 interface and one Layer 3 interface, the device needs to be rebooted. This is required to properly initialize the mixed mode configuration, as the SRX needs to switch between Layer 2 and Layer 3 processing modes.
Explanation of Answer D (Layer 2 Traffic Handling):
In mixed mode, traffic from Layer 2 interfaces is switched within the same bridge domain. A bridge domain defines a Layer 2 broadcast domain, and packets from Layer 2 interfaces are forwarded based on MAC addresses within that domain.
Juniper Security

Reference:

Mixed Mode Overview: Juniper SRX devices can operate in mixed mode to handle both Layer 2 and Layer 3 traffic simultaneously.

Juniper Mixed Mode Documentation.

Reveal Solution Next Question

QUESTION: 18

You have configured the backup signal route IP for your multinode HA deployment, and the ICL link fails.
Which two statements are correct in this scenario? (Choose two.)

The current active node retains the active role.
The active node removes the active signal route.
The backup node changes the routing preference to the other node at its medium priority.
The active node keeps the active signal route.

Answer(s): A,C

Reveal Solution Next Question

QUESTION: 19

Exhibit:

Host A shown in the exhibit is attempting to reach the Web1 webserver, but the connection is failing. Troubleshooting reveals that when Host A attempts to resolve the domain name of the server (web.acme.com), the request is resolved to the private address of the server rather than its public IP.
Which feature would you configure on the SRX Series device to solve this issue?

Persistent NAT
Double NAT
DNS doctoring
STUN protocol

Answer(s): C

Explanation:

DNS doctoring modifies DNS responses for hosts behind NAT devices, allowing them to receive the correct public IP address for internal resources when queried from the public network. This prevents issues where private IPs are returned and are not reachable externally. For details, visit Juniper DNS Doctoring Documentation.

In this scenario, Host A is trying to resolve the domain name web.acme.com, but the DNS resolution returns the private IP address of the web server instead of its public IP. This is a common issue in networks where private addresses are used internally, but public addresses are required for external clients.
Explanation of Answer C (DNS Doctoring):
DNS doctoring is a feature that modifies DNS replies as they pass through the SRX device. In this case, DNS doctoring can be used to replace the private IP address returned in the DNS response with the correct public IP address for Host A. This allows external clients to reach internal resources without being aware of their private IP addresses.
Configuration Example:
bash set security nat dns-doctoring from-zone untrust to-zone trust Juniper Security

Reference:

DNS Doctoring Overview: DNS doctoring is used to modify DNS responses so that external clients can access internal resources using public IP addresses.

Juniper DNS Doctoring Documentation.

Reveal Solution Next Question

QUESTION: 20

Exhibit:

Referring to the exhibit, what do you use to dynamically secure traffic between the Azure and AWS clouds?

You can dynamically secure traffic between the clouds by using user identities in the security policies.
You can dynamically secure traffic between the clouds by using advanced connection tracking in the security policies.
You can dynamically secure traffic between the clouds by using security tags in the security policies.
You can dynamically secure traffic between the clouds by using URL filtering in the security policies.

Answer(s): C

Explanation:

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.
Explanation of Answer C (Security Tags in Security Policies):
Security tags allow 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.

Juniper Security Tags Documentation.

Reveal Solution Next Question

Juniper JN0-637 Exam (page: 4) Juniper Security, Professional Updated on: 12-Feb-2026

QUESTION: 16

Explanation:

Reference:

QUESTION: 17

Explanation:

Reference:

QUESTION: 18

QUESTION: 19

Explanation:

Reference:

QUESTION: 20

Explanation:

Reference:

Juniper JN0-637 Exam (page: 4)
Juniper Security, Professional
Updated on: 12-Feb-2026