DIFF Subgroup
H04N 21/2542 Full Title
Selective content distribution, e.g. interactive television or video on demand [VOD] (real-time bi-directional transmission of motion video data H04N7/14 ) > Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof > Management operations performed by the server for facilitating the content distribution or administrating data related to end-users or client devices, e.g. end-user or client device authentication, learning user preferences for recommending movies > Management at additional data server, e.g. shopping server, rights management server