If you have one of the newer versions of Norton, and one of the more "modern" Windows operating systems, both can be set up to "auto-update," and will attempt to connect in order to "check for new files," often every time you boot the system, but at least periodically. It's quite possible that one of these is your culprit.
Some (possibly most) versions of pdf reader will attempt to "connect to look for updates," but usually only when you open a .pdf file. The reader invariably asks if you want to check for updates, and offers a button that you have to click to do so, so it's obvious that it's the "originator" of the request. (Some sites that offer .pdf downloads have a "check for updates" popup that will come up when you click to open a .pdf - in addition to the one that may be in your reader.)
Newer versions of Quicken and of Money will almost always attempt to "connect" when you open the program, although it's usually obvious that they're the source, since they'll whine about not knowing "which portfolio you want to check" if you haven't set them up to do something with the connection.
It is apparently the "philosopy" of a number of software bulders that everyone wants to be "connected," all the the time. They may be correct that this is a majority view, based on the vast numbers of people who apparently believe that it's impossible to operate a motor vehicle without having a cell phone stuck in their ear.
It is very likely that your unexplained attempts to connect originate from Windows, Norton, or some other "legitimate(?)" program function. It can be very difficult either to unambiguously identify or to disable this "function" - which is there "because everybody wants it.(??)"