We have a system which uses port 139 NetBIOS to broadcast, which in turn allows PC users to map drives to the server....
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BUT, our firewall team will not allow such traffic across the network. Are they being pedantic and why would they impose such restrictions. Dear Jcowie: NetBIOS over TCP/IP (port 139) is not secured and should be blocked from inbound or outbound access through the firewall to the Internet/DMZ for security reasons. To allow this port through the firewall is to defeat the purpose of having a firewall in the first place. Windows NT uses Port 139 for null sessions and for file sharing; Windows 2000 uses (for SMB) port 445 if port 139 is not enabled.
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