nwdiag {
    network external {
      tor_switch1;
      tor_switch2;
    }

    tor_switch1 -- l2_network1;
    tor_switch2 -- l2_network2;

    group {
      color = lightgreen;
      tor_switch1;
      l2_network1;
    }

    group {
      color = yellow;
      tor_switch2;
      l2_network2;
    }
}
