A Site-to-Site VPN is ideal for connecting an on-premises data center to cloud infrastructure securely over the Internet. It provides an encrypted tunnel for data to pass through, ensuring security and privacy. Site-to-Site VPNs are a cost-effective solution for permanent connections and can maintain consistent network policies between the two sites. SSL VPN is typically used for remote user access rather than site-to-site connections. Direct Connect solutions, such as AWS Direct Connect or Azure ExpressRoute, provide dedicated network connections which are not over the existing Internet connection. Network address translation (NAT) aids in remapping IP address spaces but does not establish a secure network connection between sites.