網站瀏覽計量系統(Metering Scheme)是計算網站與顧客互動次數的方法，它是利用特殊的協定或機制，紀錄網站在某一段時間之中被顧客瀏覽的次數，這些網站瀏覽計量的結果，可以被應用在計算網路廣告費用上。在1997年，Franklin和Malkhi首先就安全性的考量，提出如何計算網站流量的方法，但是他們所提出的方法只能提供輕微的安全性(lightweight security)；在1998年，Naor與Pinkas提出使用密碼學上的技巧(即polynomial secret sharing scheme)來準確地計算網站被瀏覽的次數，之後便有許多學者專家從各種不同的觀點來探討網站瀏覽計量系統。
我們經由研讀多個目前被提出的網站瀏覽計量系統之後，發現它可以經由修改秘密分享(Secret sharing scheme)的方式而達成，在本論文中，我們提出如何將秘密分享轉換成網站瀏覽計量系統的要點，並且採用基於Naor和Pinkas所提出的架構，即包含網站(Server)、顧客(Client)與審查代理商(Audit agency)三種角色，再利用中國餘定理設計一個有效率的網站瀏覽計量系統，在效率上，網站可以快速且精確計算出實際拜訪人數，並且防止不肖者蓄意破壞計量的結果，同時亦可降低顧客端的運算負荷，達到兼具有高效率且強健性(Robustness)的網站瀏覽計量系統。

Metering schemes are methods to measure the interactions between servers and clients. They use special protocols or mechanisms to calculate the number of visits, which a server receives in a certain time frame. The metering results can be used to meter the network advertisement payment. In 1997, Franklin and Malkhi were the first to use the rigorous technical approach to audit the traffic of websites, but their scheme can only offer “lightweight security”. In 1998, Naor and Pinkas proposed a metering scheme by using the cryptographic technique (polynomial secret sharing) to account the audience of websites accurately. Subsequently, many researches are proposed from different viewpoints.
We observed that secret sharing schemes are with some features related to metering schemes. It is possible to make some modification on secret sharing scheme to transform into metering schemes. In this thesis, we proposed the key points of such transformation. Then we also use the structure (i.e. servers, clients and an audit agency) proposed by Naor and Pinkas to design an efficient metering scheme based on Chinese Remainder Theorem
(CRT). Our proposed scheme enables servers to count the visits efficiently and accurately without increasing the overloads of clients and prevents the metering processes from disrupting by malicious persons. It is efficient as well as robust.

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