AT&T Corp. SBCIS-SBIS-6BLK (NET-75-47-192-0-1) 75.47.192.0 - 75.63.255.255 Private Customer - AT&T Internet Services SBC-75-51-45-104-29-1709293231 (NET-75-51-45-104-1) 75.51.45.104 - 75.51.45.111