It is standard MS 'big brother'. One of the options - within your media player settings - will be to allow sites to identify your p/c. Most people will switch this off - for obvious reasons. For subscription sites they will need to identify you (to make sure you've paid your money) or provide you with a login password. The former is better for them - as it is easier for them to record what you have been viewing, when you've been viewing and for how long etc.