Which of the following can be best defined as computing techniques for inseparably embedding unobtrusive marks or labels as bits in digital data and for detecting or extracting the marks later?
Correct Answer: B
Explanation/Reference:
Explanation:
Digital watermarking is defined as "Computing techniques for inseparably embedding unobtrusive marks or labels as bits in digital data -- text, graphics, images, video, or audio -- and for detecting or extracting the marks later."
A "digital watermark", i.e., the set of embedded bits, is sometimes hidden, usually imperceptible, and always intended to be unobtrusive. Depending on the particular technique that is used, digital watermarking can assist in proving ownership, controlling duplication, tracing distribution, ensuring data integrity, and performing other functions to protect intellectual property rights.
Incorrect Answers:
A: Steganography is a method of hiding data in another media type so the very existence of the data is concealed. Digital Watermarking is considered to be a type of steganography. However, steganography is not what is described in the question.
C: A digital envelope is another term used to describe hybrid cryptography where a message is encrypted with a symmetric key and the symmetric key is encrypted with an asymmetric key. This is not what is described in the question.
D: A digital signature is a mathematical technique used to validate the authenticity and integrity of a message, software or digital document. This is not what is described in the question.
References:
http://tools.ietf.org/html/rfc4949