在這篇論文中，我們提出一套在群組式點對點網路架構之下所設計的搜尋機制。首先，利用群組的概念，由相鄰近的網路節點形成多個群組；之後利用信譽度（reputation）的概念，為每一個網路節點以及每一群組計算其信譽度值（reputation score），在搜尋過程中，該信譽度值則被視為其搜尋的優先序，值越高的，表示其信譽度較好，有較高的機率從中搜尋到所要求的檔案，因此較優先被搜尋；用這樣的方式，可以避免傳統非結構式點對點網路中因訊息傳送量過多而導致網路效能低落的情形。
在我們的實驗結果中，也證明了在我們的搜尋機制下，相對於非結構式點對點網路，在搜尋過程中的訊息傳送量有很明顯減少的現象，因而使得點對點網路的搜尋更有效率。

Peer-to-peer networks receive great attention for file sharing and distribution in recent years. Searching for resources hosted on peers is a key component in p2p networks. However, the search performance of unstructured p2p systems is degraded due to excessive messages resulted from query flooding in the search phase. In this paper, we propose a searching scheme based on reputation systems to improve the search performance in peer-to-peer networks. A group-based architecture is configured and reputation scores are assigned for both peers and groups in our searching scheme. Peers and groups who provide more resources to others are rewarded with higher reputation scores and considered as better targets for searching. By properly defining the reputation score, searching in a p2p network can be more efficient and the performance of the network will be significantly improved. Simulation results show that the proposed reputation mechanism greatly improves the search performance in terms of reduction of messages in the network.

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