Which solution will meet these requirements?
Deploy a Network Load Balancer (NLB) in the networking account to send traffic to the security appliance. Configure the application accounts to send traffic to the NLB by using an interface VPC endpoint in the application accounts.
Deploy an Application Load Balancer (ALB) in the application accounts to send traffic directly to the security appliance.
Deploy a Gateway Load Balancer (GWLB) in the networking account to send traffic to the security appliance. Configure the application accounts to send traffic to the GWLB by using an interface GWLB endpoint in the application accounts.
Deploy an interface VPC endpoint in the application accounts to send traffic directly to the security appliance.
Explanations:
An NLB is designed to handle TCP traffic and would not be ideal for routing traffic to a security appliance for inspection across AWS accounts. Additionally, using an interface VPC endpoint does not support cross-account routing directly to a security appliance.
An ALB is meant for Layer 7 traffic (HTTP/HTTPS) and is not suited for direct traffic inspection by a security appliance in another account. It does not facilitate cross-account communication with a security appliance effectively.
A Gateway Load Balancer (GWLB) is specifically designed to integrate with virtual appliances, allowing for transparent network traffic inspection. By using an interface GWLB endpoint, traffic from application accounts can be directed to the security appliance in the networking account, meeting the requirement for inspection.
An interface VPC endpoint allows private connections to services, but it does not facilitate traffic redirection to a security appliance for inspection across AWS accounts. This option does not provide a way for the security appliance to inspect traffic effectively.
If I had to guess, I’d say the answer is:
Deploy a Gateway Load Balancer (GWLB) in the networking account to send traffic to the security appliance. Configure the application accounts to send traffic to the GWLB by using an interface GWLB endpoint in the application accounts.