digraph G {
    node [ shape=box ]

    ipv4addr [ label="IPv4-Addr: 9 /month" ]
    netv6vm [ label="/48 with a VM: 0 /month" ]
    vm [ label="VM: x/month, min 2.5/month" ]

    vm->netv6vm [ label="add" ]
    v6vpn [ label="IPv6VPN" ]
    v6vpn->p120

    p25 [ label="2.5/month" ]
    p120 [ label="120/year" ]

}