thinQmaster Virtual testing partner Adaptive practice exams that find your weak spots and drill them. Every answer explained. From $69
Enroll

thinQmaster

Find your exam

Five questions free, before you decide.

Step 1 · choose a vendor

In one of our camps? Your practice exams come with the tuition — they are on your study page already.

Security Fundamentals & Crypto · Advanced

Bell-LaPadula Model (BLP)

Formal confidentiality model enforcing 'no read up, no write down' using security labels.

Definition

Bell-LaPadula's simple security property prevents subjects from reading data at higher classifications, and the star (*) property prevents writing data to lower classifications. The strong star property restricts reading and writing to the subject's own level. It underpins military MAC systems but does not address integrity.

Example

A Secret-cleared user cannot read Top Secret files or copy Secret data into an Unclassified file.

Exam tip

BLP = confidentiality; Biba = integrity. Remember 'no read up, no write down.'

Related terms