If you have multiple VPN connections, you can provide secure communication between sites usingthe AWS VPN CloudHub. The VPN CloudHub operates on a simple hub-and-spoke model that you canuse with or without a VPC. This design is suitable for customers with multiple branch offices andexisting Internet connections who'd like to implement a convenient, potentially low-cost hub-andspokemodel for primary or backup connectivity between these remote offices. To use the AWS VPNCloudHub, you must create a virtual private gateway with multiple customer gateways, each withunique Border Gateway Protocol (BGP) Autonomous System Numbers (ASNs). Customer gatewaysadvertise the appropriate routes (BGP prefixes) over their VPN connections. These routing advertisements are received and re-advertised to each BGP peer, enabling each site to send data toand receive data from the other sites. The routes for each spoke must have unique ASNs and thesites must not have overlapping IP ranges. Each site can also send and receive data from the VPC as ifthey were using a standard VPN connection. Reference: http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPN_CloudHub.html