UDP ( user datagram protocol) port 500 2nd unauthorized DHCP servers, monitoring network for unencrypted data, running cipher.exe /w on 2nd unsigned code, dangers of unsigned drivers, restricting use of upgrades, default security for USB drives as risk factors controlling security vulnerabilities user accounts cleaning up, if stale configuring, to access resources group nesting structures, configuring correctly protecting user contexts user datagram protocol (UDP) port 500 2nd user rights, assigning in Default Domain Controller Policy user tickets, maximum life for user2sid tool