== Unclear section 4.10 Connection Termination == 

 Whoever added the last part in Connection Termination, can you please add some more details. I have a graduate degree in CS, but I still did not clearly understand this part: "Some application protocols may violate the OSI model layers, using the TCP open/close handshaking for the application protocol open/close handshaking - these may find the RST problem on active close." The example code is showing how NOT to do it, can you also post how to DO it? Also more clarification needed here: "For a usual program flow like above, a TCP/IP stack like that described above does not guarantee that all the data arrives to the other application." Thanks.