I have several unmarked Coaxials cables at my main distribution panel, these are probably old cables that was used by previous tenants for Bell Fibe or other unknown providers. When I receive my Fido modem how will I know which will be the active cable to plug into the modem? Do I jus experiment with all?
I believe try the fido modem on the cable one by one is the easiest way to test which one will work.
Otherwise you need to either buy some special equipement or have a technician to do this test for you.