PS3 Network Diagnosis

When my Playstation 3 fails to connect to the Internet via my home network, as it periodically does, the only thing that it tells me is in a small dialog box on the screen that says

Unable to connect to the Playstation Network.

Check your network settings by going to Settings -> Network

But I don't believe the problem is with my PS3 network settings, nor with my home network settings (access point configuration, router parameters, etc.). If I change no settings at all, but simply wait, after a few minutes/hours/days the PS3 is able to connect again, and all is well.

Now, I know that, under the covers, the PS3 is a sophisticated multiprocessing multiuser operating system, with a complete TCP/IP network stack, and so I'm sure that there are detailed error messages with full explanations of the problem logged somewhere.

But I have no idea how to get past the infuriatingly non-informative "can't connect" error, and find out what the true problem is.

Where do I find, on the Internet, the document entitled:

Getting started with learning to open the hood and look inside your Playstation 3 in order to troubleshoot and diagnose common operational problems.

Or does such a thing not exist because Sony feel that it would be giving away too many trade secrets?