The Mini DisplayPort connector used on Apple’s new MacBooks and MacBook Pros uses DPCP to prevent iTunes files from being played on devices that are not compliant with either DPCP or HDCP, a copy-protection technology used with the HDMI standard. DPCP supports the HDCP technology, but is considered a stronger level of encryption according to the Video Electronics Standard Association.
“While Apple’s own Apple TV has used HDCP to protect video files playing from its HDMI port, this is the first time we’ve heard of Apple bringing HDCP DPCP to its hardware,” David Chartier writes on ArsTechnica.
Basically, Apple is moving forward with a new standard that is not compatible with older displays. In the past, Apple has shown a willingness to forge ahead with new technology that doesn’t always play nice with the older stuff, and the decision to use the Mini DisplayPort connector on the new MacBooks and MacBook Pros ensured that DPCP and HDCP would come along for the ride.