"ping", check if node is alive ICMP --* -- ping
World Wide Web HTTP 80 TCP browsers
Secure Web HTTPS 443 SSL/TLS browsers
Name Resolution DNS 53 UDP nslookup
Secure Remote Shell SSH 22 TCP ssh (PuTTY)
Remote Desktop (Windows) RDP 3389 TCP rdesktop (a UNIX tool)
Secure Remote File Transfer SFTP 22** TCP WinSCP
Dynamic Host Configuration*** DHCP 67/68**** UDP built in Windows DHCP client, dhclient
Network file & printer sharing SMB 445 TCP the file browser's "map network drive"
+ You only need to memorize the ports that are highlighted
* Ping doesn't use the Transport Layer, so there's no associated port
** Same port as SSH because it actually uses SSH
*** Means you can join a network "on the fly" and get assigned an IP Address and find a DNS serverPort
**** 67 is for the server, 68 is for the client