{ lib, ... }: {
  options.lab = {

    networking = {
      public = {
        ipv4 = {
          router = lib.mkOption {
            type = lib.types.str;
            description = ''
              Public IPv4 address of the router.
            '';
          };
        };

        ipv6 = {
          router = lib.mkOption {
            type = lib.types.str;
            description = ''
              Publicly routable IPv6 address of the router.
            '';
          };
        };
      };

      dmz = {
        ipv4 = {
          prefixLength = lib.mkOption {
            type = lib.types.str;
            description = ''
              IPv4 prefix length of DMZ network.
            '';
          };

          dockerSwarm = lib.mkOption {
            type = lib.types.str;
            description = ''
              IPv4 address of the Docker Swarm in the DMZ.
            '';
          };


          router = lib.mkOption {
            type = lib.types.str;
            description = ''
              The router's IPv4 address on the DMZ network.
            '';
          };

          services = lib.mkOption {
            type = lib.types.str;
            description = ''
              The IPv4 address of the interface serving DHCP and DNS on the DMZ network.
            '';
          };
        };

        ipv6 = {
          prefixLength = lib.mkOption {
            type = lib.types.str;
            description = ''
              IPv6 prefix length of DMZ network.
            '';
          };

          dockerSwarm = lib.mkOption {
            type = lib.types.str;
            description = ''
              Globally routable IPv6 address of the Docker Swarm.
            '';
          };

          router = lib.mkOption {
            type = lib.types.str;
            description = ''
              The router's IPv6 address on the DMZ network.
            '';
          };

          services = lib.mkOption {
            type = lib.types.str;
            description = ''
              The IPv6 address of the interface serving DHCP and DNS on the DMZ network.
            '';
          };
        };
      };
    };
  };
}