11 lines
836 B
Markdown
11 lines
836 B
Markdown
# 5. Session Layer
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The session layer is responsible for opening and closing connections between two devices. The duration of a connection is called the session.
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The session layer ensures that the connections remains active and open so that the data being received and/or send is complete.
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For example when sending a big file to someone, which takes some time, the session layer will keep the connection open long enough to send the complete file.
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The session layer also synchronizes the data transfer with checkpoints. For example, if a 50 MB file is send to a device, the session layer could set a checkpoint every 10 MB. In case of a disconnect (session close), the session could be restored to a certain checkpoint and the data transfer can resume where it disconnected.
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This way we do not need to completely resend the file.
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