Image:Wireshark Icon.svg

It looks like Wireshark has made it to version 1.0.  Wireshark has been my favorite tool for diagnosing TCP problems in the socket code that I have worked on.  I’ve been using it since it used to be called Ethereal®.  Wireshark is a free an open source packet sniffer.  If you are trying to see what is coming over the wire, you want this tool whether you are running Windows, Unix, Linux. or Mac.