最佳密文傳輸率的公開金鑰背叛者追蹤系統

A Public-Key Traitor Tracing Scheme with Optimal Transmission Rate

陳毅睿(Yi-Ruei Chen)

指導教授 ： 曾文貴

國立交通大學/資訊學院/資訊科學與工程研究所/碩士(2009年)

https://doi.org/10.6842/NCTU.2009.00210

摘要

如何在廣播環境中傳送加密的數位內容給合法的訂閱者是一個在許多的商業模式中 (像是付費電視、DVD等) 很廣泛的議題。而在這樣的環境中，為了要能夠有效嚇阻合法的數位內容訂閱者將其所擁有合法解密金鑰洩露出去，背叛者追蹤系統便因應而生了。在這篇論文中，我們提出了一個背叛者追蹤系統，其所使用的廣播金鑰可以是公開的。而且在我們的系統中，密文的傳輸率可以達到最佳 (也可以說是常數密文傳輸量)，也就是說，幾乎不需要多餘的頻寬即可加密傳送數位內容。而在追蹤背叛者的能力方面，我們提出的的系統可以支援黑盒追蹤，也就是說，我們可以在不能直接察看非法解密器內部的情形下，仍然可以成功追蹤出該非法解密器是使用哪些背叛者的金鑰。而跟之前的所提出的一些相關系統相比，我們的系統在廣播金鑰以及使用者解密金鑰上，皆可以達到較低的儲存空間需求。

關鍵字

背叛者追蹤

並列摘要

The way of transmitting the encrypted digital contents to the legitimate subscribers in a broadcast environment is a wide application for many commercial transactions (e.g. pay-TV, DVD, etc.). In order to discourage the legitimate subscribers from giving away their decryption keys, the traitor tracing system is very useful. In this paper, we propose a traitor tracing scheme in which the encryption key for broadcasting can be published and our scheme has optimal transmission rate. In another word, while transmitting the digital contents, our scheme can encrypt nearly without any redundancy. As for tracing, our scheme can support black-box tracing, i.e., knowing the legitimate subscribers who leak their decryption keys out without opening the pirate decoder to check the decryption inside. Moreover, comparing to the previous schemes, the storage requirements for legitimate subscribers and digital content broadcasters can be smaller.

並列關鍵字

traitor tracing ； fingerprinting code ； all or nothing transform ； transmission rate

參考文獻

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