Data position measurement (DPM) is a copy protection mechanism that operates by measuring the physical location of data on an optical disc. Stamped CDs are perfect clones and always have the data at the expected location, while a burned copy would exhibit physical differences. DPM detects these differences to identify user-made copies. DPM was first used publicly in SecuROM 4.7.
Famous quotes containing the words data, position and/or measurement:
“To write it, it took three months; to conceive it three minutes; to collect the data in it—all my life.”
—F. Scott Fitzgerald (1896–1940)
“You will belong to that minority which, according to current Washington doctrine, must be protected in its affluence lest its energy and initiative be impaired. Your position will be in contrast to that of the poor, to whom money, especially if it is from public sources, is held to be deeply damaging.”
—John Kenneth Galbraith (b. 1908)
“That’s the great danger of sectarian opinions, they always accept the formulas of past events as useful for the measurement of future events and they never are, if you have high standards of accuracy.”
—John Dos Passos (1896–1970)