Planning Your Domain Name
At first glance, deciding what the domain name will be for your business or organization may seem like an easy task. However, this aspect of developing your infrastructure should be given careful consideration. The domain name you choose will become the root domain for your Active Directory-naming convention, and all other domain names will be derived from this root domain. When determining your domain name, there are some specific points to keep in mind:
Your domain name should be a recognizable, friendly name.
Your domain name should be global. In other words, it should apply to all divisions and groups within the business or organization.
Your domain name should be static.
Your domain name should be able to accommodate any organization growth.
When you consider the issues of a static name and one that can accommodate growth or organizational changes, you realize that in most cases, the name of your business or organization is going to be your best choice. Common domain names, such as microsoft.com, prenhall.com, and amazon.com, reflect the name of the business and are easily recognizable. In most cases, your company name is going to be your best choice. The problems occur when you have companies that have merged and are still recognized by several public names. If you intend to have one directory tree, you will have to establish a domain name to represent the individual company names.
Once you establish the name you want to use, you have to determine which domain will be the root domain. This is established by installing the Active Directory in that domain (which is the first domain in which the Active Directory is installed). This domain becomes the root domain, and all other domains in your organization become subdomains or child domains. If you have a single domain environment, your task is easy. However, many larger organizations have multiple domains. In this case, you probably want to install the root domain at the company's headquarters or largest domain. Once this is done, the other domains can become subdomains of the root, as shown in the example in Figure 5.
Figure 5 Root domain and subdomains.
As noted earlier, the task of determining your domain name may seem easy, but proceed carefully. All decision-makers within the organization should agree on the domain name, and you should consider any future events you may be aware of. Is the company going through reorganization? Will the company be merging with another company? These questions should be considered before implementing the domain name. Once the domain name is implemented and the Active Directory is installed, you will have to completely reinstall the Active Directory tree, which is not a simple or quick task.