P2P网络中稳定节点会话序列特征分析

Analysis of session sequence of stable peers in P2P networks

给出稳定节点的形式化定义,提出一个从所有节点中分离稳定节点的方法以及分析稳定节点会话序列特征的数学模型。针对KAD中的稳定节点得到以下新的重要结论:稳定节点数目仅约占总节点数目的0.6%;约70%的稳定节点通过多次会话保证长时间在线,且会话时长之间的差异很大;其余约30%的稳定节点的总会话时长远低于前者,但是它们很少离线且平均会话时长约为前者的1.8倍。这两类稳定节点可作为超级节点,发挥各自长处构造层次P2P网络。

A formal definition of stable peers was presented,a novel method to separate stable peers from all peers and an analysis of the session sequence of stable peers in P2P networks.This study uses the KAD,a P2P file sharing system with several million simultaneous users,as an example and draws some significant conclusions about stable peers： the stable peers is about 0.6% of all peers;the 70% of stable peers possess very long total session time ensured by a large number of sessions,and possess large difference between session time;the 30% of stable peers,whose average session time is 1.8 times of the former,possess long total session time,a small number of sessions and high availability.That these two types of stable peers can play their respective roles in constructing hierarchical P2P networks.