Error Detection – Across OSI Layers Explained

lanlayer2Networkosiwan

Confusion:
How does the transmitter know that his information( bits in physical layer, frames in data link layer, packet in network layer ) was transmitted correctly to the receiver?
I know that in the data link layer that is responsible ensuring that frames has been transmitted successfully by sending acknowledgement, but I just get confused on how the three layers communicate with each other on solving this problem.

Best Answer

I know that in the data link layer that is responsible ensuring that frames has been transmitted successfully by sending acknowledgement

That is incorrect. There are very few data-link protocols that do this. The transport protocol is normally where acknowledgement takes place, but not all transport protocols do that. TCP does, but UDP does not. With a connectionless transport protocol, it is up to the application to do that.

The protocols in the different layers don't really know about each other. There are fields in a protocol header (e.g. EtherType for ethernet, or Protocol for IPv4) that tell a protocol to which process it should send the payload of its protocol.

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