Does Restarting Your Router Change Your IP Address?

When you consider your IP address, you might wonder: does it change when you restart your router? This article will explore whether your internal and external IP addresses are affected by a router restart, provide detailed explanations, and guide you through the process of testing this theory.

Understanding Your IP Address

First, it is crucial to distinguish between two types of IP addresses:

The internal IP address is assigned to devices on your local network, such as the IP address of the device you are using on your WiFi network. The external IP address is the one assigned by your Internet Service Provider (ISP) and is visible to the internet.

Typically, the device's IP address on your WiFi network does not change when you restart your router. However, your router might request a new IP address from your ISP, which could result in a change for the external IP address.

Does Restarting Your Router Change the Internal IP Address?

Generally, the internal IP address remains the same even after a router restart. The router's internal IP addresses (often in the 192.168.x.x range) are typically set to a static value by your router's configuration and are not affected by the router's restart cycle.

Does Restarting Your Router Change the External IP Address?

The external IP address assigned by your ISP can change, but it does not always happen immediately after the router restarts. Here's why:

1. Internet Service Provider (ISP): If your ISP renews your IP address in a DHCP process, you might end up with a different IP address. However, ISPs often hold IP addresses for a short period to prevent connectivity disruptions.

2. Modem Power Cycle: To test whether the external IP address changes, unplug your modem, wait for a few minutes, and then plug it back in. Then, run a speed test to check the new IP address. If it remains the same, your modem may need to be unplugged for a longer period—up to 4 hours—before a new IP address is assigned.

3. ARP Tables: ARP (Address Resolution Protocol) tables in your network hardware are refreshed every 4 hours by default, which can affect the distribution of IP addresses. Unplugging the modem can also clear these tables, potentially resulting in a new IP address.

What About Restarting the Modem?

Restarting your modem can indeed change your external IP address. Since the modem is the point of connection to your ISP, unplugging it and waiting for a few minutes (or longer) before reconnecting can result in a new IP address assignment.

ISPs and IP Address Management:

ISPs have different policies regarding IP address management. Some ISPs assign IP addresses on a per-connection basis, while others change them periodically. If you have a static IP address provisioned by your ISP, your external IP will not change. This is less common, and most household connections experience IP address changes upon router restarts.

Testing the Theory

To test whether a router restart changes your IP address, follow these steps:

Unplug your modem for at least a few minutes. Plug it back in and wait. Use an online speed test tool to check your external IP address. If the IP address remains the same, try leaving your modem unplugged for a longer period—up to 4 hours.

By following these steps, you can determine whether your IP address changes after a router restart. This process can be useful for troubleshooting internet connectivity issues or ensuring that your IP address is fresh and up-to-date.

Conclusion

Whether restarting your router changes your IP address depends on the type of IP address being considered and the policies of your ISP. Internal IP addresses usually remain the same, while external IP addresses can change, especially after a power cycle of your modem. By understanding these concepts and testing the changes, you can maintain a smoother internet connection.