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A PLAY ON DATA

by Tom Cantrell

Start ı Oops ı Once More, With Feeling ı Optical Options ı Have It Your, and Our, Way ı Lesson Learned ı Sources and PDF

HAVE IT YOUR, AND OUR, WAY

DataPlay uses the amorphous media scheme like CD-RW but with a unique twist. DataPlay disks can include both pre-mastered content (like a CD) and user-recorded data (see Photo 2). Itıs kind of like having a chip thatıs half ROM and half flash memory.

(Click to enlarge)

Photo 2ıA unique advantage for DataPlay is the ability to combine pre-mastered and user-recorded data. Wobble in the grooves is the basis for timing and tracking.

The major impetus for the dual capability is DataPlayıs ContentKey scheme. Itıs designed to allow an authorized (i.e., paying) customer to gain temporary or permanent access to some or all of the pre-mastered content.

Itıs not hard to imagine useful scenarios made possible by this concept. Imagine a disk with a large collection of music or software. The disk itself can be stamped out in high volume and distributed widely at a low cost, perhaps even for free.

Then, individual users can pay to enable access to the particular content thatıs of interest to them. The payment might occur initially at a checkout stand or vending machine kiosk or maybe portions of the content could be enabled over time via the Internet.

As shown in Figure 2, a DataPlay disk is divided into a number of regionsıthe mastered file system and content, and various writeable areas.

(Click to enlarge)

Figure 2ıBuy now, pay later is an option with the DataPlay ContentKey system that relies on encryption, a pre-mastered file system, and hidden data areas accessible only to the drive, not the user.

Notice that some portions of the disk associated with the ContentKey scheme are writeable only by the drive itself, not the user.

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