Physical vs Logical Network Ports | Generated by AI
Question: Why am I confused between ports like 22 and 443 and the physical ports on switches?
Answer:
You’re confusing two completely different types of “ports” in networking—they share the same word but mean very different things.
Physical Ports
These are the actual hardware connectors on devices like network switches, routers, or computers.
- They are usually RJ45 Ethernet jacks where you plug in Ethernet cables.
- A switch has multiple physical ports (e.g., 8-port, 24-port) to allow many cables to connect multiple devices physically.
- They handle the electrical signals for data transmission over cables.
Logical Ports (or Software/TCP/UDP Ports)
These are virtual/numerical identifiers used in software and network protocols (TCP/IP).
- They range from 0 to 65535 and help computers distinguish between different services or applications running on the same device/IP address.
- Examples:
- Port 22: Commonly used for SSH (secure remote access).
- Port 443: Used for HTTPS (secure web browsing).
- Port 80: HTTP (regular web).
- Data packets include these port numbers so the receiving computer knows which program (e.g., web browser or SSH client) should handle the data.
- These have nothing to do with physical connectors—they exist only in the network stack software.
In summary: Physical ports connect cables/hardware; logical ports direct data to specific software services. They operate at different layers of the networking model.
References:
- https://www.lifewire.com/computer-port-usage-817366
- https://en.wikipedia.org/wiki/Port_(computer_networking)
- https://www.cloudflare.com/learning/network-layer/what-is-a-port/
- https://jdtechsolutions.net/what-is-are-network-port-and-how-they-work/