Some of the useful ports are:

                                  Some of the useful ports are:

Port Name	Port Number
ftp	21/tcp
Ssh	22/tcp
telnet	23/tcp
Stmp	25/tcp
htpp	80/tcp
Kerberos	88/tcp
Pop3	110/tcp
Imap	143/tcp
https	443/tcp
Ftps-data	989/tcp
Ftps	990/tcp
Telnets	992/tcp
Imaps	993/tcp
Pop3s	995/tcp
Ldap	389/tcp