4SDMI? Secure Digital Music Initiative Who: Conglomerate of world-wide recording, consumer electronic, and information technology corporationsPurpose: To design and implement a copyright protection scheme for musicHow: Digital Watermarking
5MP3 Nirvana? Joe’s friend, Dave, sends him a new NSync mp3 Joe loves the song and wants to listen to it on his new mp3 playerBut a slight problem arises
6Rejection Dave’s mp3 turns out to be watermarked only for his use Joe’s mp3 player rejects Dave’s NSync mp3 because it detects the mp3 watermark registered to Dave
7Breakin’ the LawJoe decides to hack and remove the watermark on Dave’s mp3 so his mp3 player will play the songHe uses the attacks described in a research paper released by Princeton’s professor Felton
8What Is Watermarking?Digital information embedded within any digital media that can later be detected and extractedCharacteristicsPerceptible or ImperceptibleRobust or Fragile
9Watermarking Applications Applications includeAuthentication and verificationFingerprintingOwnership AssertionContent labelingUsage Control
10Authentication and Verification Use of any type of watermark to authenticate files and digital mediaVerification allow users to download files in an insecure channelSimilar to a cryptographic hash sent with a file but much more difficult for an attacker to forge and insert a correct watermark
11FingerprintingImperceptible watermarks used to label content for identification purposesIf content is copied and improperly used, the watermark can be viewed and the source of the copying can be foundIf Joe Wahoo distributes music with his watermark embedded, any authority with the watermark directory can track him down
12Ownership AssertionA watermark can be placed in a music document to declare who owns/ produces the musicThis is basically used to remove the “value” of the data, in a lot of circumstances since it asserts it as the owners intellectual property or copyright
13Content LabelingInvolves using watermarks to carry and deliver data on the media they are embedded withinUses within databases and search enginesAdvantage in that description of data is internally stored within file
14Usage ControlA proposed use for watermarking could be to control accessing and copying music.The theory is that when a copy is made, some counter in the file is decremented.This requires a monopoly on copying.
15Problems with Watermarking Must not be audible and change little content of MP3 filePlain text to “message” will always be availableMust be universally accepted by software developers that make encoding software and players
16Plaintext/Ciphertext Attacks The plaintext is always available for the MP3 file so, therefore, any attackers can see the additions the watermark makes (and remove them)Ease of removal is variable, depending on the algorithm used
17Universal AcceptanceAs long as users can rip MP3’s without watermarks, piracy will always proliferateIf the MP3 players and portable devices play unwatermarked MP3’s, there’s no point in having the system in place at all
18ConclusionWatermarking is useful in a lot of circumstances. Digital music isn’t one of them.If someone wants to remove music watermarking, with all current algorithms, they will be able to.RIP Napster. We’ll miss you.