(User Datagram Protocol) A protocol within the TCP/IP protocol suite that is used in place of TCP when a reliable delivery is not required. There is less processing of UDP packets than there is for TCP. UDP is widely used for streaming audio and video, voice over IP (VoIP) and videoconferencing, because there is no time to retransmit erroneous or dropped packets.
If UDP is used and a reliable delivery is required, packet sequence checking and error notification must be written into the applications.
UDP is "connectionless" and does not use a handshake to start a session. It just sends out packets. See TCP, TCP/IP and RTP.
UDP Within an Ethernet Frame
A UDP packet is framed just like a TCP packet. This shows a UDP packet in an Ethernet frame ready for transmission over the network.
If UDP is used and a reliable delivery is required, packet sequence checking and error notification must be written into the applications.
UDP is "connectionless" and does not use a handshake to start a session. It just sends out packets. See TCP, TCP/IP and RTP.
UDP Within an Ethernet Frame
A UDP packet is framed just like a TCP packet. This shows a UDP packet in an Ethernet frame ready for transmission over the network.
 | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2008 The Computer Language Company Inc. All rights reserved. |
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