Port 20 (TCP)
- FTP - File Transfer Protocol, Data
- FTP supports file trabsfer between dissimiliar systems.
Port 21 (TCP)
FTP - File Transfer Protocol - Control
- SSH - Secure Shell or Secure Socket Shell
- Used for accessing a remote computer securely.
Port 23 (TCP)
- Supports dumb terminal connection and emulation with remote servers.
Port 25 (TCP)
- SMTP - Simple Mail Transfer Protocol
- Provides a mechanism foe the exchange of mail information between systems.
Port 53 (UDP,TCP)
- DNS - Domain Name Server
- Through DNS, a common naming convention is provided throughout the Internet.
Port 67 (UCP)