I'm in the middle of doing a short piece of coursework for a computer networking module using wireshark/ethereal to monitor tcp segments of a file transfer.
Hopefully there is someone familiar with tcp that can help me.
I have two queries, I have set my MTU (largest packet size) to 1500 yet when doing a file transfer my packets only seem to be 1400.
Secondly, one part of the trace shows duplicate ACK's being received from the server. How could this occur? A packet is sent from client to server and is ACK'd perfectly fine. Yet 2 more ACK's are then received which cause a retransmission of the original packet, and another 2 duplicate ACK's.
Sorry if its hard to understand, see img for better detail.
Hopefully there is someone familiar with tcp that can help me.
I have two queries, I have set my MTU (largest packet size) to 1500 yet when doing a file transfer my packets only seem to be 1400.
Secondly, one part of the trace shows duplicate ACK's being received from the server. How could this occur? A packet is sent from client to server and is ACK'd perfectly fine. Yet 2 more ACK's are then received which cause a retransmission of the original packet, and another 2 duplicate ACK's.
Sorry if its hard to understand, see img for better detail.
