If you connect your enterprise to the Internet, you are using an Internet service provider (ISP). ISPs can be large corporations, such as telephone companies, or small businesses that provide specialized services. In any case, ISPs can provide more than the telecommunication link to the Internet.
The services ISPs can provide include DNS servers and databases. You can choose to use only DNS servers and services provided by your ISP, only your own enterprise DNS name servers, or some combination.
If yours is a small enterprise, perhaps using a single computer running Windows NT Server with Internet Information Server, you may want to use only the DNS services and technical experience provided by your ISP. An ISP can help you choose and register your enterprise domain with InterNIC and maintain DNS servers and resource records with your enterprise computers' name- to - IP address mappings.
The domain name options that an ISP can offer your company's Internet site include the following:
yourcompany.ISPname.com. This form means your enterprise is a subdomain in the ISP enterprise domain.
yourcompany.com. This form means your enterprise is its own domain and is not a subdomain of any other enterprise.
Many enterprises prefer the second option because such a name identifies an enterprise as a second-level enterprise. The second option also allows flexibility in choosing an ISP. If you use the second option, you do not need to change and reregister the enterprise domain if you later switch to a different ISP.
If you choose to provide your own DNS server and services and use your ISP only for a telecommunications link, you are responsible for administering the DNS server and database files that contain the name-to-IP address mappings for computers in your intranet domain. You must create name-to-IP address mappings for any computer that has a static IP address (that is, a permanent IP address). Such computers include any Windows NT Server computer configured with Internet Information Server with services that will be accessed by users on the Internet.
Note
If you are using dial-up networking to connect to your ISP, see the section "Configuring Dial-Up Networking for ISP DNS," later in this chapter.