Computers work with IP addresses rather than the names and URLs that people use. Your computer has an IP address, your router has an IP address, a NAS (network attached storage) drive has an IP address, even wireless printers have IP addresses. How do you find out the IP addresses of devices when you need to know them?
Why would you need to know them? There are several reasons, for example, suppose you want to configure the router on your home or work Wi-Fi network or wired LAN, check its settings, or see whether it is working properly. The way to access it is to enter its IP address into the address box of a web browser. It then displays the router’s home page and login form. But what is the router's IP address?
You might want to ping a device and this means sending a standard message, a sort of “Hello, are you there?” The device responds with the equivalent of “Yes, I am.” Pinging actually sends packets of network data rather than text messages, but the effect is the same. If you want to know whether your wireless printer is OK you can ping it, but only if you know its IP address.
So how do you discover the IP address of devices? Open an Explorer window and select Network in the left pane. This shows NAS drives (often in the Media Devices section), your router (under Network Infrastructure), and printers:
Right click any of these devices and select Properties from the menu that is displayed. Here is a typical Properties window and it is for a wireless printer:
Other devices have a similar properties window. The IP address of the printer can clearly be seen and there is even a hyperlink that opens a web browser window and goes to the IP address. This is handy for routers, NAS drives and other devices that are configured through a web browser.
One thing you can’t do is to right click your own computer and get a similar properties window. We need to use another technique.
Hold down the Windows key and press R to open the Run window. Enter cmd and the command prompt window opens. At the command prompt, enter ipconfig:
This displays a lot of information, but the important one is the IPv4 address on the active network adapter. You might have more than one network adapter, such as Wi-Fi and LAN, and in the screen shot, VirtualBox adds a virtual network adapter too. It adds to the confusion, but in the screen shot the first IPv4 address is the correct one for this PC. The default gateway in the listing is the router.
Now that we have all the IP addresses, let’s ping the wireless printer to make sure it is OK. We discovered that the IP address is 192.168.1.68 in the Properties window. So at the command prompt we ping that address:
The important line is the one that says Packets: Sent=4, Received=4, Lost=0. If the printer was faulty then packets would be lost, it will take a long time (waiting for a response that never comes), and so on. It might even say ‘Destination unreachable’. You can see that this printer is OK, well it's responding on the network anyway, it won't tell you if there is a paper jam of course and this is just a network test.
Knowing how to discover IP addresses of devices on your network is useful and it can be used to solve problems. If you manually allocate IP addresses rather than letting the network automatically assign them, it is even more essential to know how to check what device is using which IP address.