Virtual Private Networks
Sidhartha Chauhan, James A. Devine, Alan Halachmi, Matt Lehwess, Nick Matthews, Steve Morad, Steve Seymour · 2018
This chapter offers guidance on how to design Virtual Private Networks (VPNs) on AWS. A VPN can be set up using different protocols and technologies, each with its own advantages. The most widely-used VPN technology is a set of protocols called the Internet Protocol Security (IPsec) protocols, often referred to as an IPsec VPN. The VGW supports both static route VPNs and those based on the BGP dynamic routing protocol. The BGP routing protocol allows the on-premises device to advertise multiple IP prefixes dynamically to the VGW using BGP route advertisements. Users can use different or the same BGP ASNs for each site based on their preference and use case. Customer gateways advertise the appropriate routes over their VPN connections. These routing advertisements are received and re-advertised to each BGP peer, enabling each site to send data to and receive data from the other sites.