// This library supports the IP version of bacnet and this is how the network packet is wrapped:
//
// UdpPacket
// |
// -> DataLink
// |
// -> NetworkPdu
// |
// -> ApplicationPdu
//
// NOTE: Pdu stands for Protocol Data Unit
// The starting point for using this library is DataLink::new()
// Network Layer and Data Link Layer
// Application Layer
// Common functions and constants