[Cisspstudy] Security Models

[Nimal Gunarathna]

Hi,
 
This question is from Shon H's CISSP V4 Quiz Engine. I immediatly thought that this fall
into a certain security model based on a key statement here but I was wrong. Anyway you guys could dissect this ... 
 
Don is a senior manager of an architectural firm. He has just found out that a key contract was renewed, allowing the company to continue developing an operating system that was idle for several months. Excited to get started, Don begins work in the operating system privately, but cannot tell his staff until the news is announced publicly in a few days. However, as Don begins making changes in the software, various staff members notice changes in their connected systems, even though they work in a lower-security level. What kind of model could be used to ensure this does not happen?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://cccure.org/pipermail/cisspstudy_cccure.org/attachments/20090625/762eb572/attachment.html>