1. ICWS 2003 Implementing Watermark Token in WS-Security for Digital Contents Distribution Presenter: Patrick Hung patrick.hung@csiro.au patrick.hung@c Co-authors: S.C. Cheung scc@cs.ust.hk scc@cs.ust.hk Hanif Curreem: hanif@cs.ust.hk Dickson Chiu kwchiu@acm.org kwchiu@a

2. 2June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Outline Introduction Watermarking Protocol Rights Token in WS Security DiscussionConclusion Future Work

3. 3June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Introduction Digital rights enforcement has drawn much attention lately Billions of dollars are lost annually Billions of dollars are lost annually P2P applications promote unauthorized copying P2P applications promote unauthorized copyingWhy? Digital contents are easy to duplicate without distortions Digital contents are easy to duplicate without distortions Compression techniques can cut down file size effectively (MP3, DivX) Compression techniques can cut down file size effectively (MP3, DivX)

4. 4June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Introduction (con’t) How to prevent Encryption Encryption Not effective since decrypted content is vulnerable to recording No rights information is stored in decrypted content Digital Rights Management Systems (DRMS) Digital Rights Management Systems (DRMS) Watermarks are usually used. Rights information can be inserted as imperceivable signals Watermarks are hard to remove without the proper insertion key

5. 5June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermarking Protocol 1 Uses encrypted watermark to avoid exposure of the original watermark Prevents unethical merchants from framing buyers for illegal content distribution The buyer is not required to submit his watermark or other evidence in case of a dispute Introduction of watermark certificate (WCert) Our protocol should support both direct purchase and re- selling transactions 1 S.C. Cheung and Hanif Curreem, Rights Protection for Digital Contents Redistribution Over the Internet, in the Proceedings of 26th International Computer Software and Applications Conference (COMPSAC 2002), IEEE Computer Press, Oxford, United Kingdom, August 2002, pp. 105-110.

6. 6June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermarking Protocol Consists of four subprotocols: 1. Watermark Generation Protocol 2. Watermark Insertion Protocol 3. Copyright Violator Identification Protocol [illegal copy found] Merchant Buyer Content Distributor Watermark Certification Authority 4. Dispute Resolution Protocol Judge

7. 7June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermarking Protocol A) Watermark Generation Protocol 1) Bob (Buyer) sends his PKI certificate Cert to WCA 1) Bob (Buyer) sends his PKI certificate Cert to WCA 2) WCA generates W and returns the watermark certificate WCert B to Bob 2) WCA generates W and returns the watermark certificate WCert B to Bob

8. 8June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermarking Protocol (con’t) B) Watermark Insertion Protocol 1) Bob (Buyer) sends his WCert B and Sign(H(  )) to Alice (Merchant) 1) Bob (Buyer) sends his WCert B and Sign(H(  )) to Alice (Merchant) 2) Alice redirects WCert B and Sign(H(  )) to CD (Content Distributor) 2) Alice redirects WCert B and Sign(H(  )) to CD (Content Distributor)

9. 9June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermarking Protocol (con’t) B) Watermark Insertion Protocol (con’t) 3) CD generates V’ (transaction identifier), X’ (content) and retrieves  (permutation function). 3) CD generates V’ (transaction identifier), X’ (content) and retrieves  (permutation function). 4) CD store transaction details to its database 4) CD store transaction details to its database

10. 10June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermarking Protocol (con’t) B) Watermark Insertion Protocol (con’t) 5) CD generates E KB (X’   (W)) 5) CD generates E KB (X’   (W)) 6) Bob retrieves E KB (X’   (W)) and recovers X’   (W) using his private PKI key. 6) Bob retrieves E KB (X’   (W)) and recovers X’   (W) using his private PKI key.

11. 11June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermarking Protocol (con’t) C) Copyright Violator Identification Protocol 2: Extract V’ 3: Is V’ found in database?

12. 12June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermarking Protocol (con’t) D) Dispute Resolution Protocol 1) Judge verifies Sign(E KB (W)) in WCert B 1) Judge verifies Sign(E KB (W)) in WCert B 2) Judge encrypts Y to E KB (Y) and checks if E KB (  (W)) can be extracted from it 2) Judge encrypts Y to E KB (Y) and checks if E KB (  (W)) can be extracted from it  )), E KB (X’) Sign(H(  )), E KB (X’)

13. 13June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Implementation Framework in Web Services

14. 14June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Watermark Token in SOAP Header <S:Envelope xmlns:S="http://www.w3.org/2001/12/soap-envelope" xmlns:wsse="http://schemas.xmlsoap.org/ws/2002/04/secext" xmlns:wm="http://schemas.xmlwatermark.org/wm/2003/06/watermark">... 1.0 93856543 SHA1RSA GTE CyberTrust WCAWCA Hanif Curreem, O=HKUST, C=HK buyer 045FB… md5RSA......

15. 15June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Conclusion Our proposed protocol relies mainly on the security of the underlying watermarking and encryption schemes. As for the encryption schemes, we have used the RSA cryptosystem. As for the encryption schemes, we have used the RSA cryptosystem. For the watermarking scheme, we have not yet identified a watermarking scheme which is certified to be both secure and robust. However, our proposed protocol does not rely on a specific watermarking scheme except that it must be linear. For the watermarking scheme, we have not yet identified a watermarking scheme which is certified to be both secure and robust. However, our proposed protocol does not rely on a specific watermarking scheme except that it must be linear. The digital signature of the permutation function relieves buyers from submitting their confidential watermarks to the judge in dispute resolution. Our protocol allows the secrecy of watermarks the distribution of rightful digital contents over the Internet. We demonstrate our model in the context of Web services environment. An implementation approach is proposed to encapsulate a watermark into a watermark token in a SOAP header.

16. 16June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Future Work Improve the performance of our system Optimize the code, try using various RSA key length Optimize the code, try using various RSA key length Investigate which watermarking scheme work best for our protocol Research on new watermarking protocol that supports copyrights in peer-to-peer sharing

17. 17June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Q & A

18. 18June 03 - ICWS03 Implementing Watermark Token in WS-Security for Digital Contents Distribution Permutation Function (optional) Permutation function void permutefunc(VLONG wmark[], int size, int seed) { int i, index1, index2; srand(seed); for (i=0; i < rand() % 100 + 50)// min. 50 times, max 150 times { VLONG tmp; index1=rand()%size;index2=rand()%size; // swap the two watermark coefficient tmp = wmark[index1]; wmark[index1]=wmark[index2];wmark[index2]=tmp;}}