Apparently this problem is common with Windows 8 with many complaints about the same thing. They only show up because there is a problem, otherwise these WAN drivers stay hidden unless you change the view settings.
Microsoft says that they have a fix for this problem and talks about the reason why the problem occurs in the first place.
Code 31 error in Device Manager for WAN Miniport (Network monitor) device in Windows 8 or Windows Server 2012
According the Msoft,
This issue occurs because Windows cannot load the drivers that are required for the WAN (Network monitor) device. Because there is no driver associated with the device, it cannot be removed from Device Manager.
One person posted this as a fix:
I FINALLY RESOLVED THIS PROBLEM! This is what I did:
So, to remove each non-working miniport, do the following:
1.Right click on the non-working miniport, choose “Update Driver”.
2.Choose “Browse my computer”.
3.In the next window, choose “Let me pick driver from a list”.
4.Uncheck “Show compatible hardware”. From the “Manufacturer” list, choose “Microsoft”, and from the “Network Adapter” list, choose “Generic Mobile Broadband Adapter”. (It can be any device the user is allowed to uninstall.)
5.Back in the device manager, delete the device that just turned into the “Generic Mobile Broadband Adapter” device.
Once done removing the bad miniports, reboot computer. Don’t skip this, it’s important. Otherwise there is a change things will go bad again.
Source:
windows 8 wan miniport issue - Microsoft Community