The VPN gateway moon controls the access to the hosts alice and
venus by means of X.509 Attribute Certificates. Access to alice
is granted to members of the group 'Research' whereas venus can only
be reached by members of the groups 'Accounting' and 'Sales'. The roadwarriors
carol and dave belong to the groups 'Research' and 'Accounting',
respectively. Therefore carol can access alice and dave
can reach venus.