A connection between the subnets behind the gateways <b>moon</b> and <b>sun</b>
is set up using the IKEv2 key exchange protocol. The authentication is based on
locally imported <b>X.509 certificates</b>.
In order to test the established tunnel, client <b>alice</b> behind gateway <b>moon</b>
pings client <b>bob</b> located behind gateway <b>sun</b>.