Question 20 - JN0-637 discussion

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. Reference: Juniper Secure Wire Documentation.