CD key
From Free net encyclopedia
A CD key is a specific software-based key for a certain program or a computer game. It is used to identify that the copy of the program/game is original. For official products the key might be used offline, at other times with software like Windows XP it is activated online to prevent multiple people using the same key.
The term CD key very likely comes from the fact that the key is usually on the case or the CD. Computer games use CD keys to verify that the game has not been illegally copied; for example, one could not play Diablo II online without an original/unique CD key. Another example is Battlefield 2 will not allow you to play online when two CD-Keys are online at the same time.
CD keys consist of a series of numbers and/or letters. This sequence is then passed to a verification function in the program. This function manipulates the key sequence according to a mathematical algorithm and attempts to match the results to a set of valid solutions.
Effectiveness
Most CD keys are not effective in stopping software piracy due to the rise of the internet, as CD keys can be distributed in seconds via CD key generators, and software publishers are increasingly turning to new methods of authenticating software, such as via internet authenticating systems.
However some CD key systems can be highly effective like Steam, the recent system implemented by Valve Software in the game Half-Life 2. There are harsh penalties of misusing CD keys, such as not being given access to the game but users may also lose access to their other legal games as a direct result (some 20,000 people found this out the hard way [1]).
Volume License Keys
It is inaccuate to call Microsoft Volume License Keys a CD key because the same keys are used across the organizion.