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USER DATAGRAM PROTOCOL (UDP) 
(see RFC 768)
User Datagram Protocol is utilized to send data that doesn't necessarily need to be very 
reliable. The UDP packet is encapsulated in an IP packet which in turn is encapsulated in 
a PPP packet. Both UDP and IP have checksums octets and the PPP packet has its FCS octets 
however this can only guarantee that the data and the destination are correct. However, 
there is a possibility that this data does not belong to an expected message sequence but
is rather part of another message that just happened to have the same destination. This issue
is addressed by the TCP protocol.

UDP is a simple to implement protocol because it does not require to keep track of every 
packet sent or received and it does not need to initiate or end a transmission. Because of 
this it is mainly designed for communications where you either don't care what the response 
will be or you pretty much know it. UDP messages are generally faster than TCP provided that 
the communication link functions properly. UDP is widely utilized to send DNS (Domain Name Search) 
requests, to exchange chat messages, or to access telephone numbers via Internet.
UDP HEADER FORMAT

OCTET 1,2	Source Port
OCTET 3,4	Destination Port
OCTET 5,6	Length
OCTET 7,8 	Checksum
OCTET 9,10…..	Data

UDP PACKET (Example)

04 89 00 35 00 2C AB B4 00 01 01 00 00 01 00 00 00 00 00 00 04 70 6F 70 64 02 69 78 06 6E 
65 74 63 6F 6D 03 63 6F 6D 00 00 01 00 01

UDP Header	04 89 00 35 00 2C AB B4
Data		00 01 01 00 00 01 00 00 00 00 00 00 04 70 6F 70 64 02 69 78 06 6E 65 
		74 63 6F 6D 03 63 6F 6D 00 00 01 00 01

Source Port		04 89
Destination Port	00 35
Length			00 2C
Checksum		AB B4
Data			DNS Message
Click Next for UDP Checksum calculation code.

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