This hour covered some key features of TCP/IP's Transport layer. You learned about connection-oriented and connectionless protocols, multiplexing and demultiplexing, and ports and sockets. This hour also introduced TCP/IP's Transport layer protocols, TCP and UDP, and described some important TCP and UDP features. You learned how TCP fulfills the TCP/IP objective of providing end-node verification. You also learned about TCP data format, flow control, and error recovery, and the three-way handshake TCP uses to open a connection. This hour also described the format of a UDP header.