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  歷史上,MAC與作為保護美國等級資訊的多層安全(MLS)手段密切相關。可信計算機系統評估標準(TCSEC)就是就這一主題的開創性工作,其中將MAC定義為“基於物件中包含資訊的敏感性(由標籤表示)來顯示對物件的訪問途徑以及物件訪問這種敏感資訊的授權”。MAC的早期實現有Honeywell的SCOMP、USAF SACDIN、NSA Blacker,以及的波音MLS LAN。  術語MAC中的“強制性”已經因其在軍事系統中的使用而獲得了特殊含義。在這方面,MAC意味著非常高的抵抗性,確保控制機制能夠抵抗任何型別的破壞,從而使他們能夠執行由政府命令授權的訪問控制,諸如面向美國等級資訊的第12958號行政命令 。強制施行的保證性要求要高於商業應用,因此這不允許採用“盡力而為”的機制。MAC只接受能夠絕對或者幾乎絕對地保證任務執行的機制。這點對於不熟悉高保證策略的人來說可能很困難或者被假定為不切實際。

  

  在某些系統中,使用者有權決定是否向其他任何使用者授予訪問許可權。為允許這點,所有使用者都必須有所有資料的審查許可。這不是MLS系統所需必要條件。如果個人或程序可能被拒絕訪問系統環境中的任何資料,則系統必須可信以強制執行MAC。由於可能存在各種級別的資料等級和使用者許可,這也顯示了健壯性的量化指標。例如,一個包含等級為最高機密的資訊和等級為未批准的使用者的系統相較於一個包含等級為絕密的資訊和等級為祕密的使用者的系統具有更高的健壯性。為了維持健壯性量化指標的一致性以及儘可能地消除主觀人為因素,一項針對該問題的大規模科學分析和風險評估提出了標誌性的測試標準,用以量化系統的安全健壯性,並根據其能夠保證的安全等級為其分級。該結果記錄於CSC-STD-004-85。健壯性的兩個相對獨立的組成部分可以被定義為保障等級和功能性,兩者都可以被闡述為一個系統在特定標準下能夠保證的其審查的精確性。

  The Common Criteria is based on this science and it intended to preserve the Assurance Level as EAL levels and the functionality specifications as Protection Profiles. Of these two essential components of objective robustness benchmarks, only EAL levels were faithfully preserved. In one case, TCSEC level C2 (not a MAC capable category) was fairly faithfully preserved in the Common Criteria, as the Controlled Access Protection Profile (CAPP). Multilevel security (MLS) Protection Profiles (such as MLSOSPP similar to B2) is more general than B2. They are pursuant to MLS, but lack the detailed implementation requirements of their Orange Book predecessors, focusing more on objectives. This gives certifiers more subjective flexibility in deciding whether the evaluated product’s technical features adequately achieve the objective, potentially eroding consistency of evaluated products and making it easier to attain certification for less trustworthy products. For these reasons, the importance of the technical details of the Protection Profile is critical to determining the suitability of a product.  Such an architecture prevents an authenticated user or process at a specific classification or trust-level from accessing information, processes, or devices in a different level. This provides a containment mechanism of users and processes, both known and unknown (an unknown program (for example) might comprise an untrusted application where the system should monitor and/or control accesses to devices and files).

  A few MAC implementations, such as 優利系統' Blacker project, were certified robust enough to separate Top Secret from Unclassified late in the last millennium. Their underlying technology became obsolete and they were not refreshed. Today there are no current implementations certified by TCSEC to that level of robust implementation. However, some less robust products exist.
強制訪問控制(英語:mandatory access control,縮寫MAC)在電腦保安領域指一種由作業系統約束的存取控制,目標是限制主體或發起者訪問或對物件或目標執行某種操作的能力。在實踐中,主體通常是一個程序或執行緒,物件可能是檔案、目錄、TCP/UDP埠、共享記憶體段、I/O裝置等。主體和物件各自具有一組安全屬性。每當主體嘗試訪問物件時,都會由作業系統核心強制施行授權規則——檢查安全屬性並決定是否可進行訪問。任何主體對任何物件的任何操作都將根據一組授權規則(也稱策略)進行測試,決定操作是否允許。在資料庫管理系統中也存在訪問控制機制,因而也可以應用強制訪問控制;在此環境下,物件為表、檢視、過程等。