多核處理器已經被大量運用在現代的電子產品中，為了增加各個核心中的處理程序的執行效率，最底層快取可以被所有核心取用且處理程序不需要特殊權限就可以改變快取的狀態。因此，這個最底層快取的漏洞被許多應用快取的旁路攻擊利用，造成一個領域的機密資料被洩漏至另一個領域。

快取記憶體配置是應用快取的旁路攻擊的解決方法之一，動態配置的效率比靜態配置來的出色，但會遭受到根據快取分配結果來推論出機密資料的攻擊方法所攻擊。因此，許多具安全性的動態配置方法被提出並用來保護機密資料，這些方法透過不將機密程式的快取需求納入配置的演算法，藉此從快取分配結果上保護機密程式。

我們提出了一個基於超過兩個群組的安全動態快取記憶體配置方法，我們的方法將所有程式的快取需求納入產生快取分配結果的考量。如果系統有安全考量，我們的方法會啟動一個虛擬程式藉以混肴產生出來的快取分配結果。實驗結果顯示我們的方法對於靜態配置達到4.3\%的效率提升並在虛擬程式啟動時表現得比另一個具安全性的動態配置來得優秀。

In nowadays, multi-core processors are widely used in modern designs. To improve the performance of processes by all cores, the last-level cache (LLC) is shared by processes and processes can change the state of LLC without privileged permission. Therefore, a number of cache-based side channel attacks were proposed to exploit the vulnerability of LLC to leak confidential information of one domain to another domain.

Cache partitioning is a countermeasure to the cache-based side channel attacks. Dynamic cache partitioning has better performance than static cache partitioning, but suffers from the attacks that deduce the confidential information from cache allocations. Hence, several secure dynamic cache partitioning mechanisms are proposed to protect the confidential information by excluding the cache demands of confidential applications from partitioning mechanisms.

We present the M-parties partitioning, a dynamic cache partitioning that utilize all cache demands of involved applications to generate cache allocations. The M-parties partitioning activates the Dummy application to obfuscate the patterns of cache allocations if the system is in the security concerned. The evaluation results show that the M-parties partitioning achieves 4.3\% improvement over static cache partitioning when the Dummy application is deactivated and performs better than another secure cache partitioning mechanism when the Dummy application is activated.

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