Ports

• Logical communication endpoints on a computer or server
• Classified as either:
  • Inbound — Listening for connections
  • Outbound — Used to connect to a server
• Example — SSH connection with an inbound port 22 and an outbound port on the client

Port Classification

• Well-Known Ports (0-1023)
• Registered Ports (1024-49151)
• Dynamic and Private Ports (49152-65535)

Protocols

• Rules governing device communication and data exchange
• Example — HTTPS (port 443) uses the HTTPS protocol for secure web communication
• Memorization Tips
  • Memorize for each port
    • Port number
    • Default protocol
    • Support for TCP or UDP
    • Basic description of the port or protocol

List of Ports and Protocols

• Port 21: FTP (File Transfer Protocol) - TCP
• Port 22: SSH, SCP, SFTP - TCP
• Port 23: Telnet - TCP
• Port 25: SMTP (Simple Mail Transfer Protocol) - TCP
• Port 53: DNS (Domain Name System) - TCP/UDP
• Port 69: TFTP (Trivial File Transfer Protocol) - UDP
• Port 80: HTTP (Hypertext Transfer Protocol) - TCP