Understanding Risk Management

Information Security, like all security, needs to be managed on a risk management basis.  

This is a fundamental principle that was prior advocated for the Department of Homeland Security, by the former Secretary Michael Chertoff.  

The basic premise is that we have limited resources to cover ever changing and expanding risks, and that therefore, we must put our security resources to the greatest risks first.

Daniel Ryan and Julie Ryan (1995) came up with a simple formula for determining risks, as follows:

Risk = [(Threats x Vulnerabilities) / Countermeasures)]  x  Impact

Where:

- Threats = those who wish do you harm.

- Vulnerabilities = inherent weaknesses or design flaws.

- Countermeasures = the things you do to protect against the dangers imposed.

[Together, threats and vulnerabilities, offset by any countermeasures, is the probability or likelihood of a potential (negative) event occurring.]

- Impacts = the damage or potential loss that would be done.

Of course, in a perfect world, we would like to reduce risk to zero and be completely secure, but in the real world, the cost of achieving total risk avoidance is cost prohibitive. 

For example, with information systems, the only way to hypothetically eliminate all risk is by disconnecting (and turning off) all your computing resources, thereby isolating yourself from any and all threats. But as we know, this is counterproductive, since there is a positive correlation between connectivity and productivity. When connectivity goes down, so does productivity.

Thus, in the absence of being able to completely eliminate risk, we are left with managing risk and particularly with securing critical infrastructure protection (CIP) through the prioritization of the highest security risks and securing these, going down that list until we exhaust our available resources to issue countermeasures with.

In a sense, being unable to "get rid of risk" or fully secure ourselves from anything bad happening to us is a philosophically imperfect answer and leaves me feeling unsatisfied--in other words, what good is security if we can't ever really have it anyway?

I guess the ultimate risk we all face is the risk of our own mortality. In response all we can do is accept our limitations and take action on the rest.

(Source Photo: here with attribution to martinluff)

Understanding Risk Management