In a variable phased valve lifter of an internal combustion engine, a roller lifter is allowed to move along a constraining member of a constraining mechanism, and the constraining mechanism is allowed to move freely in a direction substantially parallel to a line perpendicular to the flat surface machined onto the roller lifter. Aspects of the invention enable content providers cost-effective content delivery using, for example, download and peer-to-peer mechanisms, while also allowing content providers the ability to control and restrict usage of the content and combat piracy. The apparatus may also include one or more additional body sensors configured to sense a user’s position, movement, andor physiological status. The reception unit receives from a peripheral a response packet corresponding to the control packet transmitted from the transmission unit.