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Your first step in taking responsibility for your own internetworking success: becoming adept at gathering all the information you really need. This is what separates the newbies from the veterans. The veterans won't be satisfied with just knowing how to use a network. They want to figure out a little more clearly what happened if they suddenly can't connect to their favorite network destinations. Before you can figure out what's going on, you need to gather any information pertinent to your connection and destination.
The two tools that you need to start this information gathering exercise are whois and ipconfig. They are different tools and not necessarily even part of TCP/IP, but they are the place to start.