網路攻防的正規化模式

Attack Model of Network Security

陳周全(Chou-chuan Chen)

指導教授 ： 林金城

大同大學/電機資訊學院/資訊工程學系所/碩士(2007年)

摘要

近年來經由研究或是實務分析得知，網路攻擊是由多攻擊步驟所組合而成。攻擊者需要組合多種不同的網路攻擊手法、階段性的攻擊，逐步完成攻擊目標。防守者需要同時兼顧多個可能攻擊的途徑進行防護。但是在實際情況，因為網路環境複雜而情況多變，多步驟整合複雜度遠超過一般研究的限制。攻擊手段多而步驟複雜，如何正確組合攻擊步驟便是成功達目標的重要關鍵。
本論文提出一套模式，將網路攻防的過程藉由狀態轉換圖的方式描述，並加以轉換為博奕理論可處理的形式，再使用博奕理論之基礎針對網路攻防過程雙方之執行策略加以評估。將計算後之結果，作為策略決策的依據。並經由提出兩個應用案例，說明計算之過程與效用。在應用範例上，兩個應用案例被提出加以討論。前者案例為較簡易的網路模型，以說明應用博奕理論分析之適切性。並經由分析說明，闡述計算結果的合理性。後者案例為前者之延伸，環境較複雜，故需計算之規模也較前者龐大。藉此說明此分析模式可用於複雜之網路攻防環境，並有效的得出策略評估結果。

關鍵字

博奕理論 ； 資訊安全 ； 網路攻擊 ； 策略

並列摘要

Many existing academic researches and empirical studies show that, network attacking is composite by multiple steps of attacks. The attacker should consider and combine multiple various attacking skills and do stepwise attacking to approach the objective. On the other hand, the defender must take care of many possible attacked paths simultancely to defense the system. However, this multiple aspects situation is difficult to approach since the real case of network environment is complex and changeable and the integrated complexity of multiple aspects situation is more complex than usually limitation of study. Besides, the feature of multi-stage and complex of attacking behavior make it difficult to handle. It results that how to combine attack stage correctly becomes a key factor of successful attack.

We propose a game-theory based model to describe this complex situation. The procedure of network attack is described by state transfer graphs first. It is then transferred to a data form which the game-theory can handle. The executed strategies and procedure of both attacker and defender are then evaluated by the game theory. The calculated result plays a role of basis of decision-making. Two examples are show to explain its method and performance. The simpler one show the fitness of applying game theory to attack model. It also shows the reasonable result of computing model.

並列關鍵字

attack model ； network security ； game theory

參考文獻

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