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Click on the Applications icon
Use the search bar to search for Advanced Network Configuration
Click the + button on the window that appears to create a new connection.
Select Ethernet from the list in the drop-down menu, then click on Create…
Name your connection and navigate to the 802.1x Security tab
Select the Use 802.1x security for this connection checkbox
Configure the connection with the shown settings and click Save
To use the connection you created, click on the Network Manager icon
Click on your Wired connection
Select the 802.1x connection you created and wait 15-20 seconds for it to connect
You should now be authenticated to the 802.1x wired network.
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