Yes, RoadRunner blocks the following ports for security purposes:
•Port 138 UDP NetBIOS Datagram - Used for Windows File and Printer Sharing
•Port 137 TCP NetBIOS Session - Used for Windows File and Printer Sharing
•Port 445 SMB over TCP and UDP - As of Windows 2000, replaced the three ports listed above and still used for Windows File and Printer Sharing.
These ports are only blocked for traffic flowing into and out of your cable modem, they do not, in any way, affect local file sharing on your network, nor do they affect any P2P (Peer-to-Peer) program known.
**It should be noted, if you require access on any of these ports, RoadRunner Business Class in your area most likely does not block these ports and if they do, will likely unblock them upon request.