Comprehensive and Detailed In-Depth Step-by-Step Explanation:The customer’s request for multi-cloud Layer 7 network security in AWS and Azure, with full management control, VPN termination, and BGP routing, requires a flexible and feature-rich firewall solution. The Palo Alto Networks Systems Engineer Professional - Software Firewall documentation outlines the capabilities of its firewall products for multi-cloud environments.

VM-Series (Option A): The VM-Series firewall is a virtualized next-generation firewall (NGFW) ideal for multi-cloud deployments in AWS and Azure. It provides Layer 7 application visibility and control, full management control through tools like Panorama or Strata Cloud Manager, VPN termination (e.g., IPSec site-to-site VPNs), and BGP dynamic routing to peer with cloud and on-premises routers. The documentation highlights VM-Series as a versatile solution for public clouds, supporting custom configurations, policy enforcement, and advanced routing protocols, meeting all the customer’s requirements without the limitations of cloud-native or container-specific firewalls.

Options B (CN-Series), C (Cloud NGFW), and D (PA-Series) are incorrect. CN-Series firewalls are designed for containerized environments (e.g., Kubernetes) and do not support VPN termination or BGP routing natively, making them unsuitable for this multi-cloud, Layer 7 security use case. Cloud NGFW, while cloud-native for AWS and Azure, offers limited management control (as it is a managed service) and does not natively support VPN termination or BGP routing, as these features are handled by the cloud provider or require VM-Series integration. PA-Series firewalls are physical appliances, not virtualized or cloud-native, and cannot be deployed in AWS or Azure to meet the multi-cloud requirement.

References: Palo Alto Networks Systems Engineer Professional - Software Firewall, Section: Multi-Cloud Security, VM-Series Deployment Guide for AWS and Azure, VPN and BGP Routing Documentation.