(ISC)2 CISSP Certified Information Systems Security Professional Official Study Guide. Mike Chapple

Чтение книги онлайн.

СКАЧАТЬ a quantitative point of view, this process is relatively straightforward. You simply create a list of all the risks you analyzed during the BIA process and sort them in descending order according to the ALE computed during the impact analysis phase. This step provides you with a prioritized list of the risks that you should address. Select as many items as you're willing and able to handle simultaneously from the top of the list and work your way down. Eventually, you'll reach a point at which you've exhausted either the list of risks (unlikely!) or all your available resources (much more likely!).

      Recall from the previous section that we also stressed the importance of addressing qualitatively important concerns. In earlier sections about the BIA, we treated quantitative and qualitative analyses as mainly separate functions with some overlap. Now it's time to merge the two prioritized lists, which is more of an art than a science. You must sit down with the BCP team and representatives from the senior management team and combine the two lists into a single prioritized list.

      Qualitative concerns may justify elevating or lowering the priority of risks that already exist on the ALE-sorted quantitative list. For example, if you run a fire suppression company, your number-one priority might be the prevention of a fire in your principal place of business even though an earthquake might cause more physical damage. The potential loss of reputation within the business community resulting from the destruction of a fire suppression company by fire might be too challenging to overcome and result in the eventual collapse of the business, justifying the increased priority.

Continuity Planning

      The first two phases of the BCP process (project scope and planning and the business impact analysis) focus on determining how the BCP process will work and prioritizing the business assets that you must protect against interruption. The next phase of BCP development, continuity planning, focuses on developing and implementing a continuity strategy to minimize the impact realized risks might have on protected assets.

There are two primary subtasks involved in continuity planning:

       Strategy development

       Provisions and processes

      In this section you’ll learn about both strategy development and the provisions and processes that are essential in continuity planning.The goal of this process is to create a continuity of operations plan (COOP). The continuity of operations plan focuses on how an organization will carry out critical business functions beginning shortly after a disruption occurs and extending for up to one month of sustained operations.

      Strategy Development

      The strategy development phase bridges the gap between the business impact analysis and the continuity planning phases of BCP development. The BCP team must now take the prioritized list of concerns raised by the quantitative and qualitative resource prioritization exercises and determine which risks will be addressed by the business continuity plan. Fully addressing all the contingencies would require the implementation of provisions and processes that maintain a zero-downtime posture in the face of every possible risk. For obvious reasons, implementing a policy this comprehensive is impossible.

      The BCP team should look back to the MTD estimates created during the early stages of the BIA and determine which risks are deemed acceptable and which must be mitigated by BCP continuity provisions. Some of these decisions are obvious—the risk of a blizzard striking an operations facility in Egypt is negligible and constitutes an acceptable risk. The risk of a monsoon in New Delhi is severe enough that BCP provisions must mitigate it.

      Once the BCP team determines which risks require mitigation and the level of resources that will be committed to each mitigation task, they are ready to move on to the provisions and processes phase of continuity planning.

      Provisions and Processes

      The provisions and processes phase of continuity planning is the meat of the entire business continuity plan. In this task, the BCP team designs the specific procedures and mechanisms that will mitigate the risks deemed unacceptable during the strategy development stage. Three categories of assets must be protected through BCP provisions and processes: people, buildings/facilities, and infrastructure. In the next three sections, we'll explore some of the techniques you can use to safeguard these categories.

      People

First, you must ensure that the people within your organization are safe before, during, and after an emergency. Once you've achieved that goal, you must make provisions to allow your employees to conduct both their BCP and operational tasks in as normal a manner as possible, given the circumstances.

       Don't lose sight of the fact that people are your most valuable asset. The safety of people must always come before the organization's business goals. Make sure that your business continuity plan makes adequate provisions for the security of your employees, customers, suppliers, and any other individuals who may be affected.

      Management should provide team members with all the resources they need to complete their assigned tasks. At the same time, if circumstances dictate that people be present in the workplace for extended periods, arrangements must be made for shelter and food. Any continuity plan that requires these provisions should include detailed instructions for the BCP team in the event of a disaster. The organization should maintain stockpiles of provisions sufficient to feed the operational and support groups for an extended time in an accessible location. Plans should specify the periodic rotation of those stockpiles to prevent spoilage.

      Buildings and Facilities

      Many businesses require specialized facilities to carry out their critical operations. These might include standard office facilities, manufacturing plants, operations centers, warehouses, distribution/logistics centers, and repair/maintenance depots, among others. When you perform your BIA, you will identify those facilities that play a critical role in your organization's continued viability. Your continuity plan should address two areas for each critical facility:

       Hardening Provisions Your BCP should outline mechanisms and procedures that can be put in place to protect your existing facilities against the risks defined in the strategy development phase. Hardening provisions might include steps as simple as patching a leaky roof or as complex as installing reinforced hurricane shutters and fireproof walls.

       Alternate Sites If it's not feasible to harden a facility against a risk, your BCP should identify alternate sites where business activities can resume immediately (or at least in a time that's shorter than the maximum tolerable downtime for all affected critical business functions). Chapter 18 describes a few of the facility types that might be useful in this stage. Typically, an alternate site is associated with disaster recovery planning (DRP) rather than BCP. The organization might identify the need for an alternate site during BCP development, but it takes an actual interruption to trigger the use of the site, making it fall under the DRP.

      Infrastructure

Every business depends on some sort of infrastructure for its critical processes. For many companies, a vital part of this infrastructure is an IT backbone of communications and computer systems that process orders, manage the supply chain, handle customer interaction, and perform other business functions. This backbone consists of servers, workstations, and critical communications links between СКАЧАТЬ