digraph G {
    node [ shape=box ]
    rankdir=LR;


    label="Asymmetry in mapping IPv6 <-> IPv4"

    v4hosts [ label="IPv4 only network\n192.0.2.0/24" ]
    v4internet [ label="IPv4 Internet\n0.0.0.0/0" ]
#    nat64 [ label="NAT64 translator" ]
    v6internet [ label="IPv6 Internet\n::/0" ]

    v6lan [ label="IPv6 only network\n2001:db8::/64 " ]
    v6lan->v4internet [ label="Mapped as 64:ff9b::/96" ]

    v4hosts->v6internet [ label="No 1:1 mapping possible" style=dashed ]

}