You don't say if you already have, but I would suggest your first step should be to contact your ISP and see if there is a plugin or upgrade that will support Linux.

I guess the question is where the data are being stored: on the dongle or on the host PC, and what is actually doing the updating?

You don't say, so I am assuming:

1. You want to use this dongle on multiple platforms.
2. You would like a cumulative report of all usage over time.