CS2005 - Lecture 5 - Transport Layer I

Transport layer

Responsible for ensuring that data packets arrive accurately

How does the transport layer work?

Splits up data into smaller units and passes onto network layer

What's the relationship between the transport and network layer?

Transport Layer: provides logical communication between processes

Network Layer: provides logical communication between hosts

Process-Level Addressing

Allows transport layer to identify and differentiate between multiple processes running on single device

How process-level addressing works

Network layer identifies host and transport layer assigns a port number to each process

Multiplexing (Sender Side)

Allows data from multiple processes to be combined and sent over a single transport layer

Demultiplexing (Receiver Side)

Transport layer looks at port numbers and directs each portion of data to correct application

Integrity Checking

Ensures that the data received is accurate and hasn't been corrupted during transmission

How does integrity checking work?

Transport layer uses error detection mechanisms to verify data integrity. If errors are detected, protocols request retransmission

Connection Management (Establishment and Termination)

Allows for setup and teardown of connection between sender and receiver if using connection-oriented protocol

How does connection management work?

A connection needs to be established before data transfer begins and terminated afterwards

Acknowledgments and Retransmissions

Ensures reliable data transfer by acknowledging received data and retransmitting missing/corrupted data

How Acknowledgments and Retransmissions work

Receiver sends acknowledgments to confirm receipt of data. If sender doesn't receive an ACK, it retransmits the data

Flow Control

Manages the rate of data transmission to prevent overwhelming the receiver