Chapter 6: Transport Layer

•  Layer 4
• The process to communication between two computers through a connection-oriented protocol to transfer data.
• The transport layer provides end-to-end data transport services and establishes the logical connection between two communicating computers.
• User some type of session or virtual connection for communications to take place.
• Protocols that work at the transport layer set up connections between computer systems
• Before any connection occurs, there has to be an agreement of the following parameters:
• How much information each computer will send at a time
• How to verify the integrity of the data once received
• How to determine whether a pocket was lost along the way
•  By agreeing to the parameters before data is transferred the following advantages take place:    
• Helps provide more reliable data transfer, error detection, correction, recovery, and flow control.
• It optimizes the network services needed to perform these tasks.
• How the transport layer works:
• It’s like a bus and can carry many different application data types.
• The Transport Layer does not care what application is communicating with each other. It just provides the mechanisms to get the data from one system to another.
• It receives data from many different applications and assembles the data into a stream to be properly transmitted over the network.
• The main protocols that work with the transport layer are: TCP, UDP, Secure Sockets Layer (SSL), and Sequenced Packet Exchange (SPX).