Bell–LaPadula model
The Bell-Lapadula Model is like a game where you have to keep some secret information safe from bad guys. It is a way to make sure that only certain people can see important information and keep it secure.
Imagine you have a toy box with all your favorite toys inside. You don't want your little sister to play with your toys when you're not around. So, you put a special lock on the box that only you know the combination to. This way, nobody else can open it and play with your toys.
Similarly, in the Bell-Lapadula Model, there are different levels of information, usually called "security levels." The highest level has top-secret information that only a few people in charge can access. The lower levels have information that is less important and can be shared with more people.
The model has three main rules that everyone has to follow:
1. The "no read up" rule: You can't see information from a higher level if you're not allowed. For example, if you only have access to the "unclassified" level, you can't read information from the "top-secret" level.
2. The "no write down" rule: You can't share information from a higher level with people who don't have access to it. For example, if you have access to the "top-secret" level, you can't share that information with someone who only has access to the "secret" level.
3. The "simple security" rule: You can't change your security level unless you have authorization. For example, you can't change from the "unclassified" level to the "secret" level unless you have permission to do so.
These rules help keep the information safe and secure. Just like your toy box, you want to make sure that only the people who should have access to the information can see it, and nobody else can.
Imagine you have a toy box with all your favorite toys inside. You don't want your little sister to play with your toys when you're not around. So, you put a special lock on the box that only you know the combination to. This way, nobody else can open it and play with your toys.
Similarly, in the Bell-Lapadula Model, there are different levels of information, usually called "security levels." The highest level has top-secret information that only a few people in charge can access. The lower levels have information that is less important and can be shared with more people.
The model has three main rules that everyone has to follow:
1. The "no read up" rule: You can't see information from a higher level if you're not allowed. For example, if you only have access to the "unclassified" level, you can't read information from the "top-secret" level.
2. The "no write down" rule: You can't share information from a higher level with people who don't have access to it. For example, if you have access to the "top-secret" level, you can't share that information with someone who only has access to the "secret" level.
3. The "simple security" rule: You can't change your security level unless you have authorization. For example, you can't change from the "unclassified" level to the "secret" level unless you have permission to do so.
These rules help keep the information safe and secure. Just like your toy box, you want to make sure that only the people who should have access to the information can see it, and nobody else can.