A company is using an AWS Site-to-Site VPN connection from the company's on-premises data center to a virtual private gateway in the AWS Cloud…

The most effective solution to mitigate internet congestion issues for a Site-to-Site VPN "as quickly as possible" is to use an Accelerated Site-to-Site VPN connection. This feature leverages the AWS Global Accelerator to route traffic from the on-premises network to the nearest AWS edge location, and then across the highly available and congestion-free AWS global network to the AWS Region. According to AWS documentation, an Accelerated Site-to-Site VPN connection requires a Transit Gateway as its termination point; it cannot be attached to a Virtual Private Gateway. Therefore, the correct procedure is to create a Transit Gateway, create a new Accelerated VPN connection attached to it, and then update the on-premises customer gateway configuration.

A. An existing Site-to-Site VPN connection cannot be modified to enable acceleration. A new connection must be created specifically with acceleration enabled.

C. Accelerated Site-to-Site VPN connections are not supported on Virtual Private Gateways (VGWs). They must be attached to a Transit Gateway.

D. Procuring and provisioning an AWS Direct Connect connection is a lengthy process that involves physical cross-connects and can take weeks or months, violating the "as quickly as possible" requirement.

1. AWS Documentation, Site-to-Site VPN User Guide, "Accelerated Site-to-Site VPN connections": "An accelerated Site-to-Site VPN connection...uses AWS Global Accelerator to route traffic from your on-premises network to an AWS edge location that is closest to your customer gateway device." This document also states, "To use an accelerated VPN connection, you must create a transit gateway. You then specify the transit gateway when you create the accelerated VPN connection." This supports option B and invalidates option C.

2. AWS Documentation, Site-to-Site VPN User Guide, "Accelerated Site-to-Site VPN connections", section "Rules and restrictions for accelerated VPN connections": "You cannot enable acceleration for an existing VPN connection. You also cannot disable acceleration for a VPN connection." This directly invalidates the procedure described in option A.

3. AWS Documentation, Direct Connect User Guide, "Getting started with AWS Direct Connect": The guide outlines a multi-step process including choosing a location, ordering a connection from an AWS Direct Connect partner, and completing a cross-connect. This process is not immediate and does not meet the "as quickly as possible" requirement, invalidating option D.