雲端運算是近年來最熱門的研究議題，越來越多的公司進入雲端的市場來提供服務。因為這股風潮，使得雲端的資訊安全議題也逐漸受到重視。在雲端中，越來越多新型的攻擊手法出現。為了防禦這些攻擊，人們想將入侵偵測系統套用在雲端環境中。而傳統的入侵偵測系統無法對內部環境所發動的攻擊做偵測與防禦，必須做一些架構上的變更。故開始有些論文開始探討如何雲端入侵偵測系統的架構。然而，現今的架構都有缺陷。本論文試著探與不同架構中的優缺點，分析彼此的優劣。最後再並針對缺點加以改善。另外本篇論文也提供一個有一部份在探討如何提出集中控管雲端環境。也會針對現有的方式進行分析與比較優劣。

Cloud computing is a hot issue in recent years. A lot of company offer the cloud service. Therefore, the cloud security issues have become more and more important and new attack methods appear. For defensing these attacks, people want to combine the IDS (Intrusion Detection System) and the cloud environment. However, the traditional IDS can't detect the attack which is inside of the cloud, it must change the architecture. However, the architecture must have drawbacks in nowadays. In this thesis, we try to analysis the advantages and disadvantages in different architectures and improve the drawback. Otherwise, we have another part to discuss that how to have a centralized management in cloud environment.

1. Introduction
2. Background
3. Related Work
4. Attack Model
5. Design architecture
6. Implementation
7. Analysis
8. Conclusion

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