This mechanism states that in order to ensure the security of a mechanism depended upon by all users, sharing of the mechanism needs to be limited. In order to do this, minimize the total amount of mechanism common to more than one user. This means that having some application or service run from a website easily accessible by everyone, as well as depended on by everyone, could possibly be very insecure. If an attacker or group of them are able to compromise the service, they can potentially make the entire system inaccessible.
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