The roadwarriors <b>carol</b> and <b>dave</b> set up a connection to gateway <b>moon</b>.
The authentication is based on Pre-Shared Keys (<b>PSK</b>) followed by extended
authentication (<b>XAUTH</b>) of <b>carol</b> and <b>dave</b> based on user names and passwords.
Next <b>carol</b> and <b>dave</b> request a <b>virtual IP</b> via the IKEv1 Mode Config protocol
by using the <b>vips = 0.0.0.0</b> parameter.
The virtual IP addresses are registered under the users' XAUTH identity.
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Upon the successful establishment of the IPsec tunnel, the updown-script automatically
inserts iptables-based firewall rules that let pass the tunneled traffic.
In order to test both tunnel and firewall, <b>carol</b> and <b>dave</b> ping the client
<b>alice</b> behind the gateway <b>moon</b>.
