U3. Labels & Access Control

Information may only flow from an entity with a particular security label to an entity with at least the same label
1. Low level subject may not read up
  1. high level subject may not write down
    1. Principles of Bell-LaPladula
Protection Rings
1. Different subjects & Objects given different numbers (labels)
  1. OS enforces control of the layers being accessed
    1. OS controls outer layers accessing inner layers
      1. All done in a controlled manner
2. Figure shows lowest number as most important
VSTa Microkernel
1. Needs work??
Bell-LaPladula
1. Based on a confidentiality policy
2. When a subject reads and object, info flows from Object to Subject
3. When writing to an object, info flows from Subject to Object
4. Can write up or on your level, but cant read up
5. Can write on your level and read down, but cant write down

Resumen del Recurso

	Creado por Craig Parker hace más de 10 años