A technique for security and authentication on block-based media includes involves the use of protected keys, providing authentication and encryption primitives. The carton can be shipped in a relatively flat configuration, but folds to a useful and interesting three-dimensional shape. The layer includes a discontinuous fiber composite that is composed of randomly oriented short fibers and a cured resin matrix wherein the layer has been machined to provide a machined surface. In one configuration the debris is substantially completely sealed. Said features may include the 3-jet of said pixels.