No security without tradeoffs.

In discussions about security, the concept of “trade-offs” is very important. I recently had the opportunity to think about trade-offs when talking about security to a non-professional from a business school. In general, a tradeoff is a situation in which taking one option requires giving up another. In commerce and economics, the essence of a tradeoff is how to allocate limited resources (e.g., resources, time, and effort).

Equilibrium between supply and demand in economics and weighting in information science are typical examples of tradeoffs. These fields require optimal allocation of resources, resulting in cost-optimizing tradeoffs. For example, the idea is to optimize costs in a particular phase by considering resources, time, and effort in three dimensional coordinates.

Tradeoffs require optimizing various factors. How to optimize resources is not only a topic of economics, but is also important in the context of security. For example, in cases where terrorists have inflicted massive damage at low cost, the attackers have made very effective trade-offs. By compartmentalizing their organization in multiple layers and strictly executing their plan, they minimized costs while maximizing effectiveness.

On the other hand, the same tradeoffs must be made on the side of security measures. Costs must be optimized while risks are minimized, but measuring the effectiveness of these measures is a very difficult task. In modern security and risk management, parameters must be assigned appropriately to events that have low probability but high impact.

For example, given the tradeoff between a plane crash and a car crash, the wrong choice could increase the overall cost and thus the number of fatalities. To prevent this, careful consideration must be given to how to optimize resources.

Tradeoffs also exist in security practices, even in everyday examples such as key management and time spent brushing teeth. We must maximize overall effectiveness while minimizing costs. It is often only by doing this ourselves, rather than leaving it to others, that we can be effective.

Furthermore, in security measures, the discrepancy between sense and reality can be a problem. Even if there is a sense of being protected, this is often not the case in reality. This is a similar problem in the medical field. A deep understanding of what security is and how to incorporate it into daily life and organizational operations is required.

Finally, in order to optimize security measures, it is important to identify factors such as assets to be protected, risks, costs, and effectiveness, and to make appropriate trade-offs. By following the optimization steps, security measures will be effectively implemented and risks will be minimized.

In conclusion, tradeoffs in security are inevitable and must be optimized. In order to implement effective security measures, it is essential to carefully consider how to allocate resources and what risks to tolerate in order to make the best choices.

Five-step evaluation method

There are two important aspects of the five-step evaluation method: tradeoffs can be optimized, and there are good tradeoffs and bad tradeoffs. This book states that tradeoffs can be improved by following a five-step evaluation method. Here we will explain each of those five steps one at a time.

The first step is to clarify what assets need to be protected. Without this clarity, it is impossible to determine the effectiveness of security. This is because without determining the assets to be protected, it is impossible to measure the damage. Thinking quantitatively, it is necessary to clarify which assets to protect in order to ascertain how much damage will be caused. For example, the measures will differ depending on whether the target to be protected from a terrorist attack is an airplane, an airport, or the entire transportation system.

The second step is to identify what risks the asset is exposed to. Thinking of this as “identifying the coordinate axes,” the asset to be protected can be taken as the origin and the risk factors as the coordinate axes. At this stage, specific risk factors such as monetary value and human life can be identified and parameters can be assigned accordingly.

The third step is to evaluate how much risk is reduced by the security measures. Risk is the amount of damage that would be incurred if an attack or threat were to occur, and probability is also involved. In this step, you need to consider how much risk can be minimized.

The fourth step is to evaluate the risk posed by the security measures, considering multiple coordinate axes and elevations. Usually, there are multiple coordinate axes, each of which determines an elevation, but security issues are complex and several elevations may be determined simultaneously. In addition, there are spillover effects, and countermeasures may increase the risk inversely, making the measurement a specialized and advanced task.

Finally, the fifth step combines steps 1 through 3 with step 4 to assess how much risk will ultimately be reduced. This requires balancing the cost with how much it will cost and how much the risk will be lowered. Optimization is required because lowering risk too much will increase costs.

Eventually, an optimal trade-off point should be found. This optimized tradeoff is the one where costs are minimized and risks are sufficiently lowered. It is the conclusion of this document that the optimal tradeoff can be derived by following these five steps while taking into account the multilayered coordinate axes.