graph G {
    node [ shape="box"];
    rankdir="LR";


    v6host12 [ label="IPv6 only host" color="blue" ];
    v6host22 [ label="IPv6 only host" color="blue" ];
    v6host32 [ label="IPv6 only host" color="blue" ];
    v4host12 [ label="IPv4 only host" color="yellow" ];
    v4host22 [ label="IPv4 only host" color="yellow" ];
    v4host32 [ label="IPv4 only host" color="yellow" ];

    switchboth [ label="Network Switch with NAT64", shape="oval" ];

    v6host12--switchboth;
    v6host22--switchboth;
    v6host32--switchboth;

    v4host12--switchboth;
    v4host22--switchboth;
    v4host32--switchboth;

}