UDP (User Datagram Protocol)

UDP(User Datagram Protocol) is a long standingprotocolused together withIPfor sending data when transmission speed and efficiency matter more than security and reliability.

UDP uses a simpleconnectionless communicationmodel with a minimum of protocol mechanism. UDP provideschecksumsfor data integrity, andport numbersfor addressing different functions at the source and destination of the datagram. It has nohandshakingdialogues, and thus exposes the user's program to anyunreliabilityof the underlying network; There is no guarantee of delivery, ordering, or duplicate protection. If error-correction facilities are needed at the network interface level, an application may use theTransmission Control Protocol(TCP) orStream Control Transmission Protocol(SCTP) which are designed for this purpose.

UDP is suitable for purposes where error checking and correction are either not necessary or are performed in the application; UDP avoids the overhead of such processing in theprotocol stack.Time-sensitive applications often use UDP because dropping packets is preferable to waiting for packets delayed due toretransmission,which may not be an option in areal-time system.