Redshift Enhanced VPC Routing:

• When you use Amazon Redshift Enhanced VPC Routing, Redshift forces all traffic (such as COPY and UNLOAD traffic) between your cluster and your data repositories through your Amazon VPC.
• If Enhanced VPC Routing is not enabled, Amazon Redshift routes traffic through the Internet, including traffic to other services within the AWS network.
• By using Enhanced VPC Routing, you can use standard VPC features, such as VPC security groups, network access control lists (ACLs), VPC endpoints, VPC endpoint policies, internet gateways, and Domain Name System (DNS) servers.