The Transport Layer is the fourth layer of the OSI (Open Systems Interconnection) model. Its primary function is to provide reliable or unreliable delivery of data between applications running on different hosts. Key responsibilities of the Transport Layer include:
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Segmentation and Reassembly: It breaks down large messages into smaller segments for transmission and reassembles them at the destination.
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Flow Control: It manages the rate of data transmission between sender and receiver to prevent overwhelming the receiver.
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Error Detection and Correction: It ensures that data is transmitted accurately by detecting errors and, in some cases, correcting them.
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Connection Management: It establishes, maintains, and terminates connections between applications. This can be connection-oriented (like TCP) or connectionless (like UDP).
Common protocols operating at the Transport Layer include:
- TCP (Transmission Control Protocol): Provides reliable, connection-oriented communication.
- UDP (User Datagram Protocol): Offers a simpler, connectionless communication method without guaranteed delivery.
Overall, the Transport Layer plays a crucial role in ensuring that data is delivered correctly and efficiently between applications across a network.
