Your post offers little by way of clues, eg what Operating System, what computer, what software you have installed and running, etc.
Here are one or two things to go on with;
1] If this is a Windows computer, check if Windows Updates are being downloaded. There should be a Windows Update icon in the System Tray, near the clock.
2] Are you running P2P software like Limewire, Morpheus, BitTorrent etc? If so, perhaps they are connecting up automatically. The System tray should have an icon.
Mark
After successful dailup, the connection is slow as there is data being downloaded (check at dailup status dialog box). How to discover which application is responsible for the download, which decreases the connection speed drastically!
Thank you.
Bart

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