UDP and TCP: Comparison of Transport Protocols

You have most likely heard of sockets, and are probably aware that there are two main types: TCP and UDP. When writing a network game, we first need to choose what type of socket to use. Do we use TCP sockets, UDP sockets or a mixture of both?

TCP ( Transmission Control Protocol )

• Connection based 
• Guaranteed reliable and ordered 
• Automatically breaks up your data into packets for you
•  Makes sure it doesn't send data too fast for the internet connection to handle (flow control)
•  Easy to use, you just read and write data like its a file

UDP ( User Datagram Protocol )

• No concept of connection, you have to code this yourself
•  No guarantee of reliability or ordering of packets, they may arrive out of order, be duplicated, or not arrive at all! 
• You have to manually break your data up into packets and send them 
• You have to make sure you don’t send data too fast for your internet connection to handle
•  If a packet is lost, you need to devise some way to detect this, and resend that data if necessary