Question

A modified network layer is used at both the sender and the receiver that not only prepends the header as above but also adds a trailer string “END” at the end of the message from the transport layer. What changes will need to be made to your program so that the original application layer message from the sender is still received properly by the application layer at the receiver state just a short answer.

Answer 1

So in case of the sender side, as the network layer is adding the header and also adding the "END" at the end of the packet. Thus on the receiver side, we need to remove the header and the "END" at the network layer before transferring the message to the upper layer, to the transport layer.
Thus in this way, the transport layer will receive the same message which was sent by the transport layer of the sender. So above is the modification which we need to do in order to make sure that the message is reaching properly to the receiver.

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