A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them using private IP addresses. ECSs in either VPC can communicate with each other just as if they were in the same VPC. You can create a VPC peering connection between your own VPCs, or between your VPC and another tenant's VPC within the same region. You cannot create a VPC peering connection between VPCs in different regions.
For details, see VPC Peering Connection.