Computer-Kommunkationsnetzwerke 1 (VIHIAB01)
To complete this assignment you need to have wireshark installed
and running on your computer.
To complete this assignments create a report describing your solution and the way you solved each task
(screenshots and texts are both required).
The report should be uploaded in a pdf format to our submit page before 25/10/2017 23:59!
Download the ASCII copy of Alice in Wonderland, and store this file somewhere on
Capture with wireshark the upload of this file using the below form. Solve the tasks based on this capture.
What is the IP address and TCP port number used by the client computer (source) that is transferring the
file to the server?
What is the IP address of the server? On what port number is it sending and receiving TCP segments
for this connection?
What is the sequence number of the TCP SYN segment that is used to initiate the TCP connection between the
client computer and the server? What is it in the segment that identifies the segment as a SYN
What is the sequence number of the SYNACK segment sent by the server to the client computer in reply
to the SYN? What is the value of the Acknowledgement field in the SYNACK segment? How did the server
determine that value? What is it in the segment that identifies the segment as a SYNACK segment?
What is the sequence number of the TCP segment containing the HTTP POST command?
Consider the TCP segment containing the HTTP POST as the first segment in the TCP connection. What are the
sequence numbers of the first six segments in the TCP connection (including the segment containing the HTTP
POST)? At what time was each segment sent? When was the ACK for each segment received? Given the difference
between when each TCP segment was sent, and when its acknowledgement was received, what is the RTT value for
each of the six segments?
What is the length of each of the first six TCP segments?
What is the minimum amount of available buffer space advertised at the received for the entire trace? Does
the lack of receiver buffer space ever throttle the sender?
Are there any retransmitted segments in the trace file? What did you check for (in the trace) in order to
answer this question?
How much data does the receiver typically acknowledge in an ACK? Can you identify cases where the receiver
is ACKing every other received segment
What is the throughput (bytes transferred per unit time) for the TCP connection? Explain how you calculated