Flow Control

Flow Control

• Flow control is a mechanism that regulates the flow of information among accessible objects.

• A flow between two objects obj1 and obj2 occurs when program reads values from obj1 and writes values to the object obj2.

• The flow control checks that the information contained in one object should not get transferred to the less protected object.

• The flow policy specifies the channels along which the information is allowed to move.

• The simple flow policy specifies two classes of information - Confidential(C) and non confidential(N). According to flow policy only the information flow from confidential to non confidential class is not allowed.

Convert Channel

• A covert channel is a type of attack that creates a capability to transfer information objects between processes that are not supposed to be allowed to communicate.

• This convert channel violates the security or the policy.

• The convert channel allows information to pass from higher classification level to lower classification level through improper means.

• The security experts believe that one way to avoid convert channels is for as programmers to not gain the access to sensitive data.