User Datagram Protocol, or UDP, is a TCP/IP transport layer protocol that supports unreliable, connectionless communication between hosts on a TCP/IP network.
User Datagram Protocol (UDP) is a connectionless protocol that does not guarantee delivery of data packets between hosts. It differs from its companion transport layer protocol, the Transmission Control Protocol (TCP), which is a connection-oriented protocol for reliable packet delivery. UDP offers only “best-effort delivery” services and is used for both one-to-one and one-to-many communication in which small amounts of data are exchanged between hosts. UDP is used by applications and services that do not require acknowledgments. It can transmit only small portions of data at a time because it is not capable of segmenting and reassembling frames and does not implement sequence numbers.
UDP is typically used for services that perform broadcasts. These broadcasts can be directed to one of the following:
UDP is used for the following services and functions in a Microsoft Windows networking environment:
If a router is configured to allow 255.255.255.255 broadcasts, a broadcast storm can occur on the internetwork and bring network services to a halt. You should generally configure routers to allow only directed network traffic if possible.