Question

Problem 1 (Confidentiality Policies): Why is it meaningless to have compartments, such as (UNCLASSIFIED, {NUC}) and (UNCLASSIFIED, {EUR}), at the UNCLASSIFIED level?

Problem 2 (Confidentiality Policies): Given the security levels TOP SECRET, SECRET, CONFIDENTIAL, and UNCLASSIFIED (ordered from highest to lowest), and the categories A, B, and C, specify what type of access (read, write, both, or neither) is allowed in each of the following situations. Assume that discretionary access controls allow anyone access unless otherwise specified. a. Paul, cleared for (TOP SECRET, {A, C}), wants to access a document classified (SECRET, {B, C}). b. Anna, cleared for (CONFIDENTIAL, {C}), wants to access a document classified (CONFIDENTIAL, {B}). c. Jesse, cleared for (SECRET, {C}), wants to access a document classified (CONFIDENTIAL, {C}). d. Sammi, cleared for (TOP SECRET, {A, C}), wants to access a document classified (CONFIDENTIAL, {A}). e. Robin, who has no clearances (and so works at the UNCLASSIFIED level), wants to access a document classified (CONFIDENTIAL, {B}).

Problem 3 (Confidentiality Policies): Consider the DG/UX system discussed in class. a. Why is the virus prevention region below the user region? b. Why is the administrative region above the user region?

Problem 4 (Bell-LaPadula Model): Consider a variation of Bell-LaPadula model that does not have the *-property. Which security vulnerability arise?

Problem 5 (Security Models): Compare and contrast the Biba model and Bell-LaPadula model.

Answer 1

(2).