The transport layer of the TCP/IP model performs the exact same role as its counterpart in the OSI model. Namely, it is responsible for controlling communication between the two hosts. As a brief reminder, recall that the transport layer provides the following features:
- The use of checksums to ensure data integrity
- The use of sequence numbers to ensure data is rebuilt in the correct order
- Flow control to ensure the data that's being received doesn't end up flooding the recipient device
- Multiplexing to allow a host to have multiple connections to another host
The TCP and UDP protocols can be found here again. Think back to the previous chapter. How would you describe each of these two protocols? If you said that TCP was a connection-oriented protocol that uses a system of sequence numbers and acknowledgments, you would be correct....
