These questions form the basis of the process known as risk assessment. Risk assessment is a very important part of the computer security process. You cannot formulate protections if you do not know what you are protecting and what you are protecting those things against! After you know your risks, you can then plan the policies and techniques that you need to implement to reduce those risks.
1 Steps in Risk Assessment
Risk assessment involves three key steps:
There are many ways to go about this process. One method with which we have had great success is a series of in-house workshops. Invite a broad cross-section of knowledgeable users, managers, and executives from throughout your organization. Over the course of a series of meetings, compose your lists of assets and threats. Not only does this process help to build a more complete set of lists, it also helps to increase awareness of security in everyone who attends.
An actuarial approach is more complex than necessary for protecting a home computer system or very small company. Likewise, the procedures that we present here are insufficient for a large company, a government agency, or a major university. In cases such as these, many companies turn to outside consulting firms with expertise in risk assessment, some of which use specialized software to do assessments.
1.1 Identifying assets
Draw up a list of items you need to protect. This list should be based on your business plan and common sense. The process may require knowledge of applicable law, a complete understanding of your facilities, and knowledge of your insurance coverage.
Items to protect include tangibles (disk drives, monitors, network cables, backup media, manuals, etc.) and intangibles (ability to continue processing, your customer list, public image, reputation in your industry, access to your computer, your system's root password, etc.). The list should include everything that you consider to be of value. To determine if something is valuable, consider what the loss or damage of the item might cost in terms of lost revenue, lost time, or the cost of repair or replacement.
Some of the items that should probably be in your asset list include:
You should take a larger view of these and related items rather than simply considering the computer aspects. If you are concerned about someone reading your internal financial reports, you should be concerned regardless of whether they read them from a discarded printout or snoop on your email.
1.2 Identifying threats
The next step is to determine a list of threats to your assets. Some of these threats will be environmental, and include fire, earthquake, explosion, and flood. They should also include very rare but possible events such as structural failure in your building, or the discovery of asbestos in your computer room that requires you to vacate the building for a prolonged time. Other threats come from personnel and from outsiders. We list some examples here:
2 Review Your Risks
Risk assessment should not be done only once and then forgotten. Instead, you should update your assessment periodically. In addition, the threat assessment portion should be redone whenever you have a significant change in operation or structure. Thus, if you reorganize, move to a new building, switch vendors, or undergo other major changes, you should reassess the threats and potential losses.