What Is a VPN Connection? How Do I Set the Number of VPN Connections When Buying a VPN Gateway?

A VPN connection is an IPsec connection established between a VPN gateway and an independent public IP address of an on-premises data center. You can configure multiple local subnets (VPC subnets) and remote subnets (on-premises subnets) for one VPN connection.

The number of VPN connections to be created is determined by the number of on-premises data centers. Each VPN connection can connect a VPC to only one on-premises data center.

In the preceding figure, if subnets a1 and a2 on the cloud need to communicate with subnets b1 and b2 on the on-premises network, you only need to create one VPN connection, with source CIDR blocks set to a1 and a2 and destination CIDR blocks set to b1 and b2. The following figure shows an example.