There are 2 sets of API each hosted in 2 different organisations: my client's organisation and her partner's organisation. The servers from the 2 organisations communicate between each other through the APIs hosted in each organisations. My client's APIs are hosted on AWS.
My client has requested for the communications through the APIs between the servers to be done over ipsec VPN.
Since I have to setup an ipsec VPN for the API, what do I have to do on my end and what information do I need from my client's partner to proceed with the setup? Is adding my client's partner's server IP address to a customer gateway all I need to do to set it up? I have read tutorials and many of them has the part where one side has to install a tool like OpenSwan. Should my client or her partner be the one having to setup OpenSwan?