TCP: guaranteed delivery and the correct order of the packets.
TCP vs UDP
TCP (Transmission Control Protocol)
A connection-based protocol that provides a reliable flow of data between two computers.
Example: HTTP, FTP, Telnet
Use socket
Use the packet's 5-tuple (source IP address, destination IP address, source port, destination port, and protocol number) to uniquely identifies which connection it belongs to.
UDP (User Datagram Protocol)
A protocol that sends independent packets of data, called datagrams, from one computer to another with no guarantees about arrival. UDP is not connection-based like TCP.
