until it's fixed, the company is los- ing income. What's more, the reputation of the company may be affected when users try to make purchases online only to find the site unavailable. Most users probably won't wait more than 10 seconds for a page to load if they can get the same informa- tion or products elsewhere. Imagine the impact of having a site offline for hours because of a simple mistake! Change control aims to prevent these types of outages through careful planning and acceptance methods. Achieving availability metrics such as the coveted five-nines (99.999 percent uptime) is simply not possible without change control. Human error is probably the number one cause of outages today. Change control minimizes human error in a number of ways. Embracing change control will also make you a better engineer who is better able to communicate with management. Let's take a look at some of the benefits: Change control teaches forethought A good change-control program will insist that you lay out, in detail, every step of the work you would like to do, including every command you will enter into any device you will touch. Doing this is an excellent way to think through what you will be doing. It is also an excellent way to understand how a router/switch/ firewall works, because you need to think through how your changes will affect everything else. Change control improves documentation skills Change-control programs generally involve documentation of your proposed changes before you complete them. Many engineers dislike documentation and avoid it at all costs. The best way to get over something like this is to do it regu- larly. A team of people, ranging from engineers to managers and directors, will probably review your change-control documentation. If it's not concise and clearly written, you'll end up having to answer a lot of questions and probably rewrite it anyway. Change control improves communication skills Change control usually includes a review process where your proposed change is evaluated, commented upon