INTERNET PROTOCOLS AND PORT NUMBERS

Internet Protocol Port Number FTP TCP 20/21 Telnet TCP 23 Simple Mail Transport Protocol TCP 25 DNS UDP and TCP 53 Trivial FTP (TFTP) UDP 69 Hypertext Transfer Protocol (Web) TCP 80 Kerberos logons UDP and TCP 88 Post Office Protocol v3 (POP3) TCP 110 Network News Transfer Protocol (NNTP) TCP 119 Simple Network Time Protocol (SNTP) UDP 123 NetBIOS UDP and TCP 137, UDP 138, TCP 139 IMAP4 TCP 143 SNMP UDP 161/162 LDAP TCP 389 Secure HTTP (SSL) TCP and UDP 443 SMB over sockets (CIFS) TCP/UDP 445 ISAKMP (key exchange for IPSec) UDP 500 SQL Server UDP/TCP 1433
www.nswc.navy.mil/ISSEC/Docs/Ref/Networking/new_ports.html