The roadwarriors <b>alice</b> and <b>venus</b> sitting behind the NAT router <b>moon</b>
 set up a connection to gateway <b>sun</b> using IKEv2. UDP encapsulation is used to 
traverse the NAT router.
The authentication is based on locally loaded <b>X.509 certificates</b>.
In order to test the tunnel the NAT-ed hosts <b>alice</b> and <b>venus</b> ping the client
<b>bob</b> behind the gateway <b>sun</b>.