UDP vs TCP
Can anyone explain to me the difference in the scan from dslreports UDP ports vs Shields Up TCP ??
My main issue is that Shields Up tells me that (eg) NetBios is blocked (my firewall is set to block TCP 137-139), but dslreports tells me that 137 UDP is open.
So would I need to block both TCP AND UDP ports 137-139 ??
I understand the difference between UDP and TCP as far as the re-transmits and overheads of TCP goes, but at the moment I'm assuming I'd have to block both TCP and UDP of every port I want to block.
I am running XP Pro. When I would run the scan test it showed ports 137, 138, and 139 were open. I went into msconfig to services and unchecked Netbios Helper. I rebooted and it seemed to close all three of the ports.