Every device that connects to the Internet, including computers, smartphones and game consoles, has an Internet Protocol address. This address identifies the machine online, helping data reach its destination. When you connect multiple devices on a Wi-Fi network, each has its own local IP address, which differs from the public IP address. Using Wi-Fi does not directly alter a network's public IP, but you can use Wi-Fi to connect with a different IP address.
Public and Local IP Addresses
Whether you have one computer in your home or a dozen, your connection to the Internet uses a single IP address, known as the public IP. Locally, your router assigns each device on your network a different, local IP. The router uses these addresses to distribute data to the correct machines. Because local IPs exist only within a local network, different networks can use the same local IP addresses without conflict, whereas public IPs are unique.
IP Address Changes
Most Internet connections use a dynamic IP address, meaning your Internet service provider can change your IP at any time, such as when you reboot your modem, but it may remain the same for long periods of time. Local IPs, on the other hand, change far more frequently. Simply switching your computer's Wi-Fi connection off and on may assign it a different IP, and rebooting your router will often assign new local IPs to every computer on your network. Many routers offer static local IP settings to avoid this shuffle, if desired.
Changing IP With Wi-Fi Networks
The portability of Wi-Fi makes it easier to temporarily change your IP compared to a wired connection. Whenever you connect to a different Wi-Fi network, your public IP will become that network's IP. For example, connecting your laptop or smartphone to a public hot spot at a restaurant or library will give you a different IP address than connecting at home. Keep in mind that public hot spots do not provide the same level of security as a home connection, so don't transmit sensitive data while using one.
Wi-Fi Versus Cellular IP Addresses
When using a smartphone or tablet, connecting to Wi-Fi will change both types of IP addresses compared to connecting over cellular. While on Wi-Fi, your device's public IP will match all other computers on your network, and your router assigns a local IP. While using a cellular connection, your cell carrier assigns a public IP. Connecting to the cellular Internet does not use a router, so your device won't have a local IP.
Checking Your IP Address
To find your local IP address on a Windows 8 PC, press "Windows-R," type "cmd" and press "Enter." Type "ipconfig," press "Enter" and read the line labeled "IPv4 Address." Many mobile devices show your local IP within the Wi-Fi settings. To see your public IP, you can check the configuration page for your router or modem. Alternatively, type "My IP" into Google and the results page will display your current public IP.
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