What is Port Forwarding and why it needed? Explain

You might have heard about port forwarding but weren't sure what it was or how it works. Simply put, port forwarding lets you connect to a specific computer or service over the internet. It directs incoming internet traffic to the correct server within a local TCP/IP network.

For example, if you have a web server on your local network that you want to be accessible from the public internet, you would configure your router's port forwarding settings. This involves setting the router to forward web/HTTP packets (which use port 80) to the IP address of your web server within your local network (LAN).

 

What is a Port?

A port is an endpoint for communication, which can be either hardware or software-based. It serves as a point where data is transferred or connections are established.

Examples of Ports:

1. Hardware Ports: These are physical connectors on a device that allows external devices to connect and communicate with your computer or other hardware. Examples include:

• USB Ports: Used for connecting devices like keyboards, mice, printers, and storage devices.
• HDMI Ports: Used for transmitting high-definition video and audio from a device to a display like a TV or monitor.
• Ethernet Ports: Used for wired network connections, allowing devices to connect to a local network or the internet.

2. Software Ports: These are logical endpoints used in network communications to identify specific processes or services. They are crucial for managing multiple network connections on a single device. Examples include:

• TCP Ports: Used by the Transmission Control Protocol, which provides reliable, ordered, and error-checked delivery of data. Common TCP ports include:

• Port 80: Used for HTTP (web traffic).
• Port 443: Used for HTTPS (secure web traffic).
• Port 25: Used for SMTP (email transmission).

• UDP Ports: Used by the User Datagram Protocol, which provides a faster, connectionless communication method, but without the reliability of TCP. Common UDP ports include:

• Port 53: Used for DNS (domain name system) queries.
• Port 69: Used for TFTP (trivial file transfer protocol).
• Port 123: Used for NTP (network time protocol).

Both TCP and UDP have 65,535 ports each, ranging from port 0 to port 65,535. These ports allow for numerous simultaneous connections and services on a single device, ensuring that data is routed to the correct application or service.

How to Port Forward a Router

I'll demonstrate using a TP-Link router, but these steps are similar for most routers:

Step 1: Log in to the TP-Link router

1. Find the default gateway address by typing `ipconfig` in the Command Prompt. Look for the "Default Gateway" under your network connection.

2. Open your web browser and enter the default gateway address into the address bar. This will take you to the router's login page.

3. Login using your router's username and password to get the TP-Link Dashboard.

Step 2: Access the Port Forwarding Settings

1. Once logged in, go to the "Forwarding" section.
2. Click on "Virtual Servers."

Step 3: Add a New Port Forwarding Rule

1. Click "Add New."

Step 4: Enter the Port Forwarding Details

1. Service Port: Enter the external port number you want to open.
2. Internal Port: Enter the internal port number (usually the same as the service port).
3. IP Address: Enter the IP address of the device you want to forward the port to (the local device within your network).
4. Protocol: Select "All" to cover both TCP and UDP.
5. Status: Select "Enabled."

Step 5: Save the Settings

1. Click "Save" to apply the changes.

You should now be able to connect to your device via a web browser. Simply enter your hostname followed by the port number into the address bar (e.g., `http://yourhostname:portnumber`).