Explain UDP User Datagram Protocol and how it worksSolutionU

Explain UDP (User Datagram Protocol) and how it works.

Solution

UDP Provides an unreliable packets delivery system uilt on top of the IP protocol.

As with IP,each packet is individual , and is handled seperately .because of this the

amount of data can be sent in a UDP packets is limited to the amount than can be conatined in a

single IP packets .thus a UDP packet can contain at most 65507 bytes .

                                    UDP packets arrive out of order or not at all.no packets has any knowldege of

preceding or following packets .the recipents does not acknowlege packets , so sender does not not

know that the transmission was successful.UDP has no provisions for flow control packets can received

faster than they can be used .we call this type of communication connectionless because the packets

have no relationshipto each other and because there is no state maintained .

                                The destination IP address and port number are encapsulated in each UDP packets

.these two numbers together uniquely identifiy the recipients and are used by the underlying operating

sytem to deliver the packets to a specific process . Each UDP packets also contains the sender\'s IP

address and port number.

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USING UDP

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UDP does not provide any reliability ,e.g it does not transmit any lost packets .often this main reason to consider UDP as a transport .application that do require reliable message delivery therefore need to implement appropriate protocol mechamism in their applucation .

UDP\'s best effort service does not protect against datagram duplication i.e an application may receive multiple copies of UDP datagram .applctaion designers therefore need to verify that their applcation gracefully handles datagram duplication and may need to implement mechanism to detect duplicates .

the internet may also significantly delay some packts with respect to others e.g due to routing transient ,intermittent connectivity ,or mobility. this can cause reorderiing ,where UDP datagrams arrive at the reciever iin an order different from the transmission order .application that require ordered delivery must restore datagram ordering themselves .