Page 127 - Handout Computer Network.

Computer Network 2026

However, the primary protocol operating at this layer is connection-oriented TCP. Its
main function is to transport and regulate the flow of information from source to destination
reliably and accurately.

The primary duties of the transport layer are to provide end-to-end control, to provide
flow control via sliding windows, and to ensure reliability via sequencing numbers and
acknowledgments. To understand reliability and flow control, think of a person who speaks really
fast. In conversation, the listener might need to ask this person to repeat some words if they are
not understood (for reliability) and to speak slowly, so the listener can catch the words (flow
control), as shown in Figure 6-1.

Figure 6-1 shown a Transport Layer Analogies

The transport layer provides transport services from the source host to the destination
host. It constitutes a logical connection between the endpoints of the network. Transport
services segment and reassemble data that is sent by several upper-layer applications onto the
same transport layer data stream.

This transport layer data stream provides end-to-end transport services. The transport
layer data stream is a logical connection between the endpoints of a network. The transport
layer defines end-to-end connectivity between host applications.

Figure 6-2 shown a Transport Layer Role in Communication illustrates the transport layer.

Figure 6-2 shown a Transport Layer Role in Communication The
transport layer provides the following basic services:
• Segmenting upper-layer application data

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