What is an Open Port and How to check for it?

Each internet-enabled device uses an IP Address to send and receive data. When you reach that IP address, the network can be further splintered into separate devices on the local network, such as WiFi-connected cameras, smart devices and TVs, computers, tablets, and mobile devices.

Each device connected to your Wi-Fi network then has its local IP address. For example, if I connect to 123.45.67.89 externally, I’ll hit the router in my internal network, which then assigns its own private IPs to the devices connected to the router: your TV maybe 192.168.1.30, and your MacBook maybe 192.168.1.167. On top of that, each application on a computer has a specific port that it uses.

For example, email uses port 25, web browsers use port 80, etc. Each application uses its specific port, so the intended receiver, whether it’s a computer, a gaming console, or any other device, knows exactly which application it needs to use to open the data package.

Open Ports vs. Closed Ports

An open port refers to a TCP or UDP port number configured to accept data packets. In contrast, a port that rejects connections or ignores all packets is closed. On a closed port, your router doesn’t know what to do with the incoming connection request.

By default, your router keeps all of your ports closed for you by actively rejecting incoming data packets. This is because the router has no clue where to send the incoming data packet: does it go to your PS4? Does it go to your web server in the basement? Does it go to your smart TV?

If you don’t know which computer or device on your network the incoming packet is intended for, you might experience NAT issues. However, port forwarding helps solve this issue.

Is an Open Port Safe?

By definition, in the digital world, open means you’re exposing yourself to online risks. However, open ports aren’t dangerous by default. Technically, what do you do with the open ports at a system level, and what services and apps are exposed to those ports that categorize them as dangerous?  

Open ports can be unsafe when the service listening on the port is misconfigured, unpatched, vulnerable to exploits, or has poor network security rules. In short:

• Open ports are completely safe on a gaming console (Xbox or PlayStation). Since there is no way to access your WiFi network from a gaming console, you’ve got no risk.
• Open ports on camera devices can give you access to the device. This doesn’t mean that a hacker can access your WiFi network through that device. The risk is especially low if you’ve set up a password on the camera device.
• Open ports pose a great risk on a computer device. To stay secure, ensure that you have a software firewall in place. Windows 10 provides a great firewall by default so an open port shouldn’t pose a significant risk to you.

How Do I Open a Port?

You can open a port by port forwarding at the router level. You’ll generally need to forward ports to play online games. This is because routers aren’t optimized for online gaming purposes. Apart from manually forwarding ports, you can save yourself the hassle by subscribing to PureVPN’s Port Forwarding Add-On.

This is especially beneficial in environments with large IT departments, where you don’t have access to the router’s administrative panel, or where you’re too afraid to make those changes yourself; it’s pretty daunting to make modifications on the router level if you don’t know what you’re doing or what it does.