Gebruikte poortnummers (standaard)

20 - File transfer Protocol (FTP) 21 - FTP control 22 - Secure Shell (SSH) 23 - Telnet 25 - Simple Mail Transfer Protocol (SMTP) 53 - Domain Name System (DNS) 80 - Hyper Text Transfer Protocol (HTTP) 110 - Post Office Protocol (POP3) 143 - Internet Message Access Protocol (IMAP) 389 - Lightweight Directory Protocol (LDAP) 443 - HTTP secure (HTTPS) 993 - IMAP over TLS/SSL 995 - POP over TLS/SLL