Describing the Functions at the Transport Layer

The two protocols in the TCP/IP suite that operate at the Transport layer are TCP and UDP. Both utilize port numbers to label segments with the services or applications required at the destination before handing the segment down to the Internet layer. These labels placed in the Transport header by the source device are read when the segment is at the Transport layer of the destination device. However, the services that these two protocols provide to the frame after it leaves the computer are quite different. In this section, you'll examine their characteristics.

Earlier, in the section “Comparing the OSI and TCP/IP Models,” specific differences between the two models are discussed. If you think ...

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