Other Service Packet Filtering
- Login services:
- telnet (23/tcp)
- SSH (22/tcp)
- FTP (21/tcp)
- NetBIOS (139/tcp)
- rlogin et al (512/tcp through 514/tcp)
- RPC and NFS:
- Portmap/rpcbind (111/tcp and 111/udp)
- NFS (2049/tcp and 2049/udp)
- lockd (4045/tcp and 4045/udp)
- NetBIOS in Windows NT:
135 (tcp and udp), 137 (udp), 138 (udp), 139 (tcp). Windows 2000 - earlier ports plus 445(tcp and udp)
- X Windows:
6000/tcp through 6255/tcp
- Naming services--
- DNS (53/udp) to all machines which are not DNS servers, DNS zone transfers (53/tcp) except from external secondaries
- "Small Services"-- ports below 20/tcp and 20/udp, time (37/tcp and 37/udp)
- Miscellaneous--
- TFTP (69/udp)
- finger (79/tcp)
- NNTP (119/tcp)
- NTP (123/udp)
- LPD (515/tcp)
- syslog (514/udp)
- SNMP (161/tcp and 161/udp, 162/tcp and 162/udp)
- BGP (179/tcp)
- SOCKS (1080/tcp)
- ICMP
- incoming echo request (ping and Windows traceroute)
- outgoing echo replies
- time exceeded
- destination unreachable messages
- Do not block "packet too big" messages (type 3, code 4).