CD-Cops is the first

CD-ROM A CD-ROM (, compact disc read-only memory) is a type of read-only memory consisting of a pre-pressed optical compact disc that contains data. Computers can read—but not write or erase—CD-ROMs. Some CDs, called enhanced CDs, hold both comput ...

protection that uses the geometry of the CD-ROM media rather than a hidden "mark". It was invented in 1996 by Danish Link Data Security, known for its Cops Copylock key-diskette security used in the 1990s by

Lotus 1-2-3 Lotus 1-2-3 is a discontinued spreadsheet program from Lotus Software (later part of IBM). It was the first killer application of the IBM PC, was hugely popular in the 1980s, and significantly contributed to the success of IBM PC-compatibles i ...

Overview

As a copy (

CD-R CD-R (Compact disc-recordable) is a digital optical disc storage format. A CD-R disc is a compact disc that can be written once and read arbitrarily many times. CD-R discs (CD-Rs) are readable by most CD readers manufactured prior to the in ...

) will have a different geometry, Data Position Measurement needs to be used for copies. The geometry is not known before CDs have been produced, therefore a CD-code expressing the layout of the CD-ROM must be entered the first time a user runs the protected software. Using a special production process in some cases the CD-code is embedded on the CD-ROM. CD-Cops is popular for encyclopaedias/dictionaries and business applications but not used as much for games. DVD-Cops based on the same principles in 1998 was the first

DVD-ROM The DVD (common abbreviation for Digital Video Disc or Digital Versatile Disc) is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any ki ...

protection made.

References

Sources

AnalysiscdmediaworldPDFarticle

External links

at linkdata.com

at linkdata.com Compact Disc and DVD copy protection Digital rights management for macOS {{storage-software-stub