I thought it would be helpful to me to have the common network ports handy. I am Network+ certified, but sometimes I forget them.
Port Number | Protocol | Description |
---|---|---|
20 and 21 | FTP | File Transfer Protocol is used for sending files to and from a server |
22 | SSH | The Secure Shell Protocol is used for sending encrypted data to a server |
23 | Telnet | Telnet is used for an providing an unsecure interface to a server shell |
25 | SMTP | The SMTP Protocol used for sending email between servers |
53 | DNS | The Domain Naming Service is used to match computer names to IP Addresses on a network |
67 | DHCP | The Dynamic Host Configuration Protocol enables client computers to obtain a valid IP address on a network |
80 | HTTP | HTTP allows clients to request web pages from servers |
109, 110 | POP | Allows clients to communicate with email servers to read messages in their mailbox |
137-139 | SMB | Microsoft servers use this for file and print sharing |
143, 220 | IMAP | Provides advanced mailbox services for clients |
389 | LDAP | LDAP provides access to directory services for authenticating |
443 | HTTPS | Provides encrypted communication with web servers |
2049 | NFS | Provides file sharing between Unix and Linux systems |
In my learnning environment, when I typed in cat /etc/services in bash it listed all of the services available on my linux server.