P2P技術於大型多人線上遊戲系統之研究

Abstract

隨著網路的發展與普及，大型多人線上遊戲變得非常的受歡迎，成為網路上重要的商業之一。目前大型多人線上遊戲常用的是主從式的架構，但是當有越來越多玩家同時進行遊戲時，伺服器就沒有足夠的資源來承受大量的玩家，造成遊戲反應延遲。點對點技術似乎比主從式架構更適合用在大型多人線上遊戲，因為可以將伺服器的負擔轉移到其他的客戶端一起分擔，不過也會引起更多的作弊問題。

本論文實作了利用點對點技術改良大型多人線上遊戲常用的主從式架構，結合了主從式架構與點對點技術的優點，具有以下特點：（1）解決發生在超級節點間的作弊問題。（2）藉由多層超級節點的多點傳輸樹來廣播訊息，降低伺服器的頻寬使用量。（3）低廣播時最後一個節點接收到訊息的延遲時間，進一步的，可以降低所有節點接收到訊息的延遲時間總合。

With the progress of Internet, Massively Multiplayer Online Games (MMOGs) become very popular. Now it is one of the important businesses in Internet. Traditionally, MMOGs are built based on Client/Server (CS) technology. However, when more and more players play game simultaneously, the server has insufficient resources to serve those players, which introduces more network delay. Peer-toPeer (P2P) technology seems to be more appropriate than CS because the load of the server will be shifted to clients, but it may cause more cheating problems.

In this paper, we implement an improved centralized system via P2P technology. It takes advantage of both CS and P2P as follows: (1) Against cheating that occurs in peers. (2) By using multilevel multicast tree to broadcast messages, our system reduces the bandwidth requirement of the server. (3) Reduce the message latency of the last node and the average latency of all nodes in advance.