20 common ports and their purposes

Shamsa Al Mazrooei10BG

FTP (File Transfer Protocol)

» A standard protocol for transferring files between computing systems.

Assigned to port 20 and to port 21 (mostly uses port 20).

SFTP (Secure File Transfer Protocol).

» An encrypted version of FTP, which uses Secure Shell (SSH).

Assigned to port 22.

– SMTP (Simple Mail Transfer Protocol).

» The protocol used to transfer email from a client to an email server; it is also used to transfer email between servers.

Assigned to port 25.

– POP3 (Post Office Protocol v3)

. » The protocol used by clients to retrieve email from servers.

• Assigned to port 110. Common ports and protocols.

TLS (Transfer Layer Security)

 Technology In actuality, SSL should no longer be used.

• Assigned to port 443. Common ports and protocols.

IMAP (Internet Message Access Protocol).

» A protocol used by clients to access email on email servers. Allows the client to organize email on the server into folders.

Assigned to port 143

HTTP (Hypertext Transfer Protocol).

» The primary protocol used to transfer data over the Internet.

Assigned to port 80.

. – HTTPS (Hypertext Transfer Protocol Secure).

» The primary protocol to securely transfer data over the Internet using SSL (Secure Socket Layer) or

– DNS (Domain Name System).

» The protocol that is used to map computer names to their IP addresses (e.g., www.google.com to 74.125.28.104).

• Assigned to port 53.

– RDP (Remote Desktop Protocol).

» Used in Microsoft networks by Remote Desktop Connection and Remote Assistance to make remote connections.

• Assigned to port 3389.

– DHCP (Dynamic Host Configuration Protocol).

» The protocol used within networks to automatically configure computers with the correct IP configurations (e.g., IP address, subnet mask, default gateway, and DNS server location).

.– SMB (Server Message Block). » A protocol used to transfer files over

a network; the process is transparent to the user.

• Assigned to port 445. Common ports and protocols.

LDAP (Lightweight Directory Access Protocol).

 » The protocol used for accessing and

maintaining distributed directory information services (e.g., Active Directory Domain Services).

• Assigned to port 389

– SNMP (Simple Network Management Protocol).

» A protocol used to monitor and

manage local area networks. • Assigned to port 161.

– CIFS (Common Internet File System).

» A protocol used to share files across intranets (internal private networks) and the Internet.

• Assigned to port 3020.

– Telnet

» A protocol used for remote access to systems; it is unsecure. It is a bi-directional terminal service.

• Assigned to port 23.

– SSH (Secure Shell)

  » A protocol used to encrypt data

traffic on a network. • Assigned to port 22.

Thank you!