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21 장 전송층 (Transport Layer)

21.1 Duties

21.2 Connection

21.3 OSI Transport Layer

21.4 Summary

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Internetwork

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21.1 Duties of the Transport Layer

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Duties of the Transport Layer

Transport layer compared with data link layer

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Duties of the Transport Layer

Transport layer duties

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Duties of the Transport Layer

End-to-End Delivery~ oversee the end-to-end(source-to-destination)

delivery of an entire message

Addressing~ protocol stack or service point

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Duties of the Transport Layer

Service points

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Duties of the Transport Layer

Reliable Delivery

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Duties of the Transport Layer

Error Control

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Duties of the Transport Layer

Sequence Control

Segmentation and Concatenation

Sequence Numbers

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Duties of the Transport Layer

Sequence Control

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Duties of the Transport Layer

Loss Control

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Duties of the Transport Layer

Duplication Control

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Duties of the Transport LayerFlow Control(sliding window)

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Duties of the Transport Layer

Multiplexing

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21.1 Connection

End-to-End Delivery

Connection-oriented

connection establishment

data transfer

connection termination

Connectionless

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Connection

Connection establishment

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Connection

Connection Termination

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21.3 OSI 전송층 프로토콜전송 클래스

TP0: Simple class

TP1: Basic error recovery class

TP2: Multiplexing class

TP3: Error recovery and multiplexing class

TP4: error detection and recovery class

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OSI 전송층 프로토콜TPDU(Transport Protocol Data Unit)

length( 길이 ) : TPDU 의 바이트 수

Fixed parameters :

variavle parameter : 관리 정보

Data : 상위층으로부터 받은데이터

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OSI 전송층 프로토콜Connection-Oriented and Connectionless

Service