# Matrix to Multi-level security

How to convert access control matrix to Bell-LaPadula. Can teach me step by step What best way to control converting Bell-LaPadula Model lattice using Access Control Matrix

Matrix GIVEN

$$\quad\quad\quad\quad$$O1 O2 O3 O4 S1 w r w rw S2 rw r S3 w w r S4 w w w r S5 rw rw r 

convert to BLP lattice diagram

## migrated from cstheory.stackexchange.comSep 29 '18 at 12:45

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• We discourage posts that simply state a problem out of context, and expect the community to solve it. Assuming you tried to solve it yourself and got stuck, it may be helpful if you wrote your thoughts and what you could not figure out. It will definitely draw more answers to your post. Until then, the question will be voted to be closed / downvoted. You may also want to check out these hints, or use the search engine of this site to find similar questions that were already answered. – Raphael Oct 29 '18 at 13:31

Subject S2 has read-write access to Object 1, which is something no other subject has. On the other hand, subject S2 has no rights to Objects 2 and 3, which is something no other subject has. So Subject S2 has incomparable rights to all other subjects.

Similarly S1 is incomparable to the others.

S4 clearly has more rights than S3. S5 clearly has more rights than S3.

So the subjects' "security levels" can be shown like this:

$$\,\,\,$$S5 S4 \ / S1 S2 S3

(I don't know this subject before your question so this is just my impression. This subject has been discussed in three questions at cs.stackexchange.com in the past.)

• how you get to that answer. None of the three talk about access control matrix to Bell-LaPadula Model lattice. why s1 s2 is out side. how can S5 and S4 both be upper bound in lattice – Wei Wen Sep 29 '18 at 9:03