A company is planning to migrate to AWS.

AWS Transit Gateway is the correct architecture for connecting a very large number of VPCs in a scalable hub-and-spoke model. VPC peering between more than 1,000 VPCs would create an unmanageable mesh of peering connections and route table updates. VPN tunnels are intended for encrypted connectivity over external networks, not for efficient VPC-to-VPC communication at this scale. A Direct Connect gateway is used for connecting on-premises networks to AWS and is not the right mechanism for attaching every VPC through public VIFs. Transit Gateway supports VPC attachments and centralized route tables, which makes it the operationally scalable and high-performing choice for communication among many VPCs.