How Can I Tell Who's Logged in to My Network?

Wired equivalent privacy (WEP), Wi-Fi Protected Access (WPA) and WPA2 refer to data encryption protocols that routers use to secure wireless networks. If your router doesn't have WEP, WPA or WPA2 enabled, or if the router is set to transmit an open WEP network, other users can log in to your wireless network without permission.

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If your wireless network is protected, other users can't connect to it without a pass key.

If you've left your router unsecured, and you want to find out whether or not other users have logged into your network, you can check the DHCP Client Table — a table that lists the computer devices connected to a router — for unfamiliar IP addresses.

Step

Click "Start." Input "cmd" into the search box, then press "Enter," to open Command Prompt. Type "ipconfig" into the prompt, then press "Enter."

Step

Click "Start." Input "Notepad.exe" into the search box, then press "Enter," to open Notepad.

Step

Return to Command Prompt and locate the "IPv4 Address" field. Enter the series of numbers into Notepad.

Step

Return to Command Prompt and locate the "Default Gateway" field. Enter this second series of numbers below the first series.

Step

Open a browser and type the second series of numbers into the address bar. Press "Enter" to go to the router setup page.

Step

Enter the login information into the username and password field, or enter the default credentials if you've never accessed the router setup page. If you don't know the default login credentials, check the manual that came with the router for more information.

Step

Press "Enter" or click "Log In." Click the "Network" link, then click "DHCP," or click the "Status" tab, and then click "Local Network." Look for "DHCP Client Table." Some routers also display this information on the "Home" tab.

Step

Compare the IP addresses listed in the "DHCP Client Table" with the first series of numbers you entered in to Notepad. If there are IP addresses listed that don't match your own, the unfamiliar IPs are likely assigned to users who are connecting to your network without permission.