gdef natPrivateIP 10.0.0.254
gdef natPublicIP  192.168.0.1
gdef natPrivateMac 00:00:00:00:00:01
gdef natPublicMac  00:00:00:00:00:02
gdef natPublicGwIP 192.168.0.254    // IP address of gateway in public subnet
gdef natPublicGwMac 00:00:00:00:00:03  // MAC address of gateway in public subnet