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

    label="IPv6 proxies by ungleich.ch"


    proxyv6 [ label="ungleich\nIPv6-IPv4 Proxy" ];
    proxyv4 [ label="ungleich\nIPv4-IPv6 Proxy" ];

    serverv4  [ label="IPv4 only\nServer" ];
    serverv6  [ label="IPv6 only\nServer" ];
    noipv4here [ label="No IPv4-\nhere-service" ];

    clientv4 [ label="IPv4 only\nclient" ];
    clientv6 [ label="IPv6 only\nclient" ];

    clientv4->serverv4 [ label="Direct IPv4 access" ];
    clientv6->serverv6 [ label="Direct IPv6 access" ];

    clientv4->proxyv4 [ label="Connect by IPv4" ];
    clientv6->proxyv6 [ label="Connect by IPv6" ];

    proxyv6->serverv4 [ label="Translate to IPv4" ];
    proxyv4->serverv6 [ label="Translate to IPv6" ];
    proxyv4->noipv4here [ label="If IPv4 translation is disabled" ];


    subgraph cluster_legacyserver {
        label="Enable legacy IPv4 servers to be reachable by IPv6";
        proxyv6;
        serverv4;
    }

    subgraph cluster_v6net {
        label="Enable legacy IPv4 clients to access IPv6 only servers";

        proxyv4;
        serverv6;
        noipv4here;

    }

    subgraph cluster_clients {
        label="Clients";

        clientv4;
        clientv6;


    }



}