Your company has a FastConnect circuit established between your on-premises data center and OCI.

Requirements:Encrypt FastConnect traffic with minimal bandwidth impact.

IPSec Options:

DRG VPN:Native OCI solution over FastConnect.

Firewall Appliances:Adds overhead and complexity.

Compute Instances:Resource-intensive, not scalable.

Internet VPN:Uses public internet, against requirements.

Evaluate Options:

A:DRG VPN with AES-GCM (low-overhead encryption) leverages FastConnect; optimal.

B:Firewalls with AES-256 add overhead, reducing bandwidth; less effective.

C:Compute-based VPN is inefficient and public-facing; unsuitable.

D:Public internet VPN violates privacy requirement; incorrect.

Conclusion:DRG VPN with AES-GCM is the most effective solution.

OCI supports IPSec over FastConnect via DRG. The Oracle Networking Professional study guide explains, "A Site-to-Site VPN over FastConnect using the DRG provides encrypted traffic with low-overhead algorithms like AES-GCM, maintaining high bandwidth" (OCI Networking Documentation, Section: FastConnect with VPN). This meets regulatory and performance needs efficiently.