The roadwarrior <b>carol</b> and the gateway <b>moon</b> use the <b>openssl</b>
plugin based on the <b>OpenSSL</b> library for all cryptographical and X.509
certificate functions whereas roadwarrior <b>dave</b> uses the default <b>strongSwan</b>
cryptographical plugins <b>aes des sha1 sha2 md5 gmp x509</b> plus the <b>openssl</b>
plugin for the Elliptic Curve Diffie-Hellman groups only.
<p>
The roadwarriors <b>carol</b> and <b>dave</b> set up a connection each 
to gateway <b>moon</b>. The authentication is based on <b>X.509 certificates</b>.
<b>carol</b> proposes the DH groups ECP_256 and ECP_384 whereas <b>dave</b> proposes
ECP_256 and ECP_521. Since <b>moon</b> does not support ECP_256 the roadwarriors
fall back to ECP_384 and ECP_521, respectively.
<p>
Upon the successful establishment of the IPsec tunnels, <b>leftfirewall=yes</b>
automatically inserts iptables-based firewall rules that let pass the tunneled traffic.
In order to test both tunnel and firewall, both <b>carol</b> and <b>dave</b> ping
the client <b>alice</b> behind the gateway <b>moon</b>.

