Explanation: The Amazon Virtual Private Cloud (Amazon VPC) allows the user to define a virtual networking environment in a private, isolated section of the Amazon Web Services (AWS) cloud. The user has complete control over the virtual networking environment. The organization wants to extend their network into the cloud and also directly access the internet from their AWS VPC. Thus, the organization should setup a Virtual Private Cloud (VPC) with a public subnet and a private subnet, and a virtual private gateway to enable communication with their data center network over an IPsec VPN tunnel. To setup this configuration the organization needs to use the Amazon VPC with a VPN connection. The organization network administrator must designate a physical appliance as a customer gateway and configure it. The organization would need the below mentioned information to setup this configuration: The type of customer gateway, such as Cisco ASA, Juniper J-Series, Juniper SSG, Yamaha Internet-routable IP address (static) of the customer gateway’s external interface Border Gateway Protocol (BGP) Autonomous System Number (ASN) of the customer gateway, if the organization is creating a dynamically routed VPN connection. Internal network IP ranges that the user wants to advertise over the VPN connection to the VPC.
Reference:
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_VPN.html