.. No clue who or what they are.. / turned off ans. machine .. did not answer it. Let it ring away. Let's see if they continue to call

Caller ID read Fax Global. Did not answer. - No Message left.

Do not want people calling that do not identify themselves.

Answered but no one on the line then they hung up.  Can anyone stop this?  We are on the DO NOT CALL list.

Most all Americans are on the DNC.   Unfortunately,  at this time,  no....no one can stop this.  It is pretty much up to individuals to come up with the best solutions.  Call blockers are about the best bet.  All  AT&T and other phone companies want to do is raise their rates.