次世代軟體定義網路環境下之資安風險研究

A Security Risk Research of Software Defined Network Environment

郭建廷(Chien-Ting Kuo)

指導教授 ： 雷欽隆

國立臺灣大學/電機資訊學院/電機工程學研究所/博士(2018年)

https://doi.org/10.6342/NTU201801596

摘要

軟體定義網路的概念起始於可程式化控制網路路由的網路架構。網路的管理者可透過軟體程式的操作，針對網路的封包流進行控制。在本論文中，軟體定義網路環境下的資安議題將會分成用戶終端風險資安研究，以及核心交換機網路資安研究等兩個議題進行研究討論。在用戶終端風險資安研究中，將進行資安弱點稽核與評估的方法論研究。資訊安全已經成為企業組織中重要的議題，然而人始終是在組織資安中最脆弱的一環，因此在這個論文研究中，提出動態風險評估方法以幫助企業組織中的的資安管理者了解到，終端裝置的使用者本身的資安意識以及該終端裝置的弱點評估，並透過實作的方式證明該方法的可用度。在核心交換機網路資安研究中，針對軟體定義網路中的一個假設:交換機都是可信任並遵守被交付的任務，進行探討，若該假設不成立，則可能對整體網路造成巨大的破壞。在本論文中，針對交換機可能存在漏洞被惡意使用者操作，造成假設不成立的情境中，進行惡意使用者攻擊模式的探討，並提出偵測被控制的交換機發生可疑異常行為時的偵測方法，及進一步建構彈性的偵測環境網路以避免被控制的交換機間發生共謀行為以抵抗偵測方法。總結全文，本論文針對軟體定義網路環境下的資安議題進行探討，包含從用戶終端裝置到核心交換機網路、政策面的考量到網路拓樸架構的設計、以及軟體應用層弱點到傳輸層的網路封包流，提出了完整的資安構面議題的研究探討。

關鍵字

軟體定義網路 ； 資安風險 ； 資安弱點 ； 彈性網路拓樸

並列摘要

SDN is a concept of programmable networking. A network manager can process each network flow through software programs. In this dissertation, the SDN network environment security will be separated as client-side risk security research and core network switches group security research. The client-side risk security research is focus on vulnerabilities auditing and assessment mechanism. Information security audit has become more and more important to the organizations. However, human is usually the most vulnerable part about information security in the organization. In this part, we proposed a dynamic risk assessment mechanism to help the information security manager realizing the human security awareness and vulnerability assessment in end client devices. A practical implementation demonstrates that the proposed mechanism is available. In the core network switches group part, there is a hypothesis that all switches are trusted and follow programmed commands to handle packets on SDN. That is, once a switch is compromised by an attacker and does not follow the order of the network manager, this will bring a huge network disaster. In this dissertation, some attack models through compromised switches had been defined and a detection mechanism to find these compromised devices has been designed. Briefly of this dissertation, we proposed fully security sector considerations of SDN network environment from the client-side to the core network, from the policy consideration to the technical network topology, and also from software vulnerabilities of application layer to network package flow of physical layer.

並列關鍵字

SDN ； Security Risk ； Security Vulnerability ； Flexible Network Topology

參考文獻

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