藉由分散式雜湊表(Distributed Hash Table)加入同儕式網路(peer-to-peer network)的節點(peer)，可以持有不同數量的虛擬伺服器(virtual server)，且節點可經由搬遷虛擬伺服器來使自己的負載(load)和能力(capacity)成正比。
現在並沒有具精準效能分析的分散式負載平衡演算法，如何設計一個使用虛擬伺服器的分散式負載平衡演算法是一個有難度的問題。在論文中我們提供了一個具有效能保證的分散式負載平衡演算法。經由實驗也證實了我們的方法確實比過往的演算法來的有效。

With the notion of virtual servers, peers participating in a peer-to-peer network based on
distributed hash tables (DHTs) may host different numbers of virtual servers, and by migrating
virtual servers, peers can balance their loads proportional to their capacities. Most
decentralized load balance algorithms for the DHT-based networks cannot be designed to enable
rigorous performance analysis. While designing a distributed load balancing algorithm
for DHTs with virtual servers is technically challenging, we present in this paper a novel
distributed load balancing algorithm with analytical performance guarantees. Through extensive
simulations, our proposal considerably outperforms prior algorithms in the literature.

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