Pratt IT

The Pratt School of Engineering is blocking some incoming Internet traffic via ports that are not used by the Pratt community, but are often used by hackers and worms to compromise Pratt computer systems. This is intended to have no effect on current functionality available within Pratt.

This list was developed by the Pratt Technology Services group in coordination with OIT and based on the experiences of Arts & Science Computing's current set of port filters.

Please notify the Pratt Help Desk if any service disruptions occur due to these port blocks. Ports that are found to be required for current functionality will be unblocked. Over time we will continue to review this list of ports and add or subtract ports as technology and functional requirements in Pratt change.

Ports Blocked 9/25/2003

Ports Protocol Direction Service Comments Exceptions
1 TCP IN/OUT Protect Old SGI's
67-68 TCP & UDP IN/OUT bootp/dhcp
69 TCP & UDP IN/OUT tftp Hackers use tftp constantly to download malicious code
79 TCP IN finger
135-139 TCP & UDP IN Microsoft SMB Used for shared folders. Use Duke's VPN client to mount SMB folders from outside of Duke 152.3.0.0
152.16.0.0
161 TCP & UDP IN/OUT snmp 152.3.2.0 UDP
(network monitoring)
167 UDP IN/OUT snmpd <-> routed/gated
445 TCP IN Microsoft DS Used for Microsoft Domain authentication. Use Duke VPN to log into Pratt domains from outside of Duke.
512 TCP IN rexec
512 UDP IN biff
513 TCP IN rlogin
513 UDP IN rwhod
514 TCP IN rsh
514 UDP IN syslog
517 UDP IN talk
518 UDP IN ntalk
593 TCP & UDP IN RPC encapsulated in HTTP
6667 TCP IN/OUT irc 152.3.183.72
9100 TCP IN/OUT HP JetDirect 152.3.0.0
152.16.0.0
31337 TCP IN/OUT Back Orifice

Ports that may be blocked in the future
TBD