If you've upgraded to Windows 10 then Microsoft could be using your PC - and your internet connection - to silently send Windows updates to others.
The feature used to do this is called Windows Update Delivery Optimization (WUDO). Here's how Microsoft describes it in an online FAQ:
"Windows Update Delivery Optimization lets you get Windows updates and Windows Store apps from sources in addition to Microsoft. This can help you get updates and apps more quickly if you have a limited or unreliable Internet connection. And if you own more than one PC, it can reduce the amount of Internet bandwidth needed to keep all of your PCs up-to-date."
A system that helps you save some bandwidth by sending updates to other PCs on your network. Sounds great, right? But then you read on [emphasis added]:
"Delivery Optimization also sends updates and apps from your PC to other PCs on your local network or PCs on the Internet."
So Microsoft is turning newly upgraded Windows 10 PCs into systems to effectively fileshare updates with others.
Some aspects worth highlighting:
Beyond the ability to turn the feature off or mark connections a metered, I don't see any obvious method to control how much bandwidth this feature consumes.
While WUDO doesn't present any known security risks at present, security expert Graham Cluley was keen to point out that hackers have previously managed to exploit weaknesses in the Windows Update mechanism, using it to spread the Flame malware.
Will you be leaving this feature turned on, or will you be turning it off? Leave a note in the comments below.