If I want to allow Windows networked drives between two firewalled computers, do I need to open ports 137-139, or is port 445 sufficient? I have to submit a form and get approval to open firewall ports, and I don't want to ask for more open ports than I need. All of the machines here are Windows XP or later.
Note: when I say "Windows networked drives", I'm not entirely sure whether I'm referring to SMB or CIFS, and I'm not entirely clear on the difference between the two protocols.