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OSI Transport Layer

Network Fundamentals – Chapter 4

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Transport Layer Role and Services

Explain the purpose of the Transport layer: The Transport layer prepares data for transport over the network for use by Applications

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Transport Layer Role and Services Major functions of the transport layer and the role it

plays in data networks

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Transport Layer Role and Services Supporting Reliable Communication (UDP vs TCP)

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Transport Layer Role and Services Identify the basic characteristics of the UDP and TCP

protocols

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Transport Layer Role and Services Data for different applications is directed to the correct

application because each application has a unique port number.

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Transport Layer Role and Services

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Application and Operation of TCP Mechanisms How the TCP reliability mechanism works as part of a

session

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TCP Mechanisms of Operation

Three way handshake/Window Size

Sequence numbers/Acknowledgments

Termination of Session

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Managing TCP Sessions

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Managing TCP Sessions Describe how TCP sequence numbers are used to

reconstruct the data stream with segments placed in the correct order

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Managing TCP Sessions Trace the steps used by the TCP protocol in which

sequence numbers and acknowledgement numbers are used to manage exchanges in a conversation

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Application and Operation of TCP Mechanisms Trace the steps in the handshake in the establishment

of TCP sessions

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UDP Protocol Describe the characteristics of the UDP protocol and

the types of communication for which it is best suited

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UDP Protocol Describe in detail the process specified by the UDP

protocol to reassemble PDUs at the destination device

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UDP Protocol

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UDP Protocol Trace the steps as the UDP protocol and port numbers

are utilized in client-server communication.

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Summary

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