User Datagram Protocol (UDP)

Introduction

• UDP stands for ‘User Datagram Protocol’.
• UDP is an alternative protocol of TCP that can be used in the Internet.

Definition

• The UDP is an unreliable or unsecure or no guarantee, connectionless, simpler, efficient communication protocol of the transport layer of TCP/IP protocol suite.

Feature

• UDP is also a connectionless protocol, i.e. a network node(source) can communicate with another network node(destination) using UDP protocol without prior negotiating any kind of handshaking or creating a logical connection between them. In another words, unlike TCP, there is no prior dedicated logical connection between source and destination to send and receive data. Due to this feature of UDP, it is very efficient to send very small amounts of data at irregular intervals.
• UDP is suitable for those type of communications where error checking and error correction are either not necessary or are performed in the application.
• It has 8 bytes header control structure.
• The DNS, BOOTP, DHCP, TFTP, SNMP, NTP(Network Time Protocol), NNP(Network News ) etc. protocols use UDP protocol in their operations.

Advantages

• UDP is comparatively faster than TCP.
• UDP is used by Real-Time Applications.

Disadvantages/Limitations

• UDP is an unreliable or unsecure protocol, i.e. UDP does not provide mechanisms for error detection and error correction between the source and the destination. Because of this, UDP utilized bandwidth more efficiently than TCP.
• UDP does not support retransmission technology of lost data packets.
• UDP does not support data packet reorder mechanism.
• UDP does not support Data flow control mechanism.
• UDP does not support advanced error checking mechanism rather it supports basic error checking(checksum method).
• UDP does not support Acknowledgement mechanism.
• UDP does not support Handshaking mechanism.

Use/Applications

• UDP is suitable for time-sensitive applications that can’t afford retransmission delays for dropped data packets. For examples – Voice over IP (VoIP), online games, media streaming etc.