DNS Defined - Introduction


In today’s business environment, acquiring and distributing information can be critical for success. Computer networks have strategic value for companies and can improve productivity and provide a competitive advantage.

The distributed networking style of the 1980s evolved in to the enterprise-wide networking style of the 1990s. An enterprise networking style includes individuals and LANs within company departments. It also includes suppliers, customers, distributors, and other trading partners who communicate using data, voice, and video. Thousands of enterprise networks can link together through the TCP/IP community.

The ability to reach other hosts quickly and easily is vital to network operation. A key ingredient is that network hosts have identifiable names that the myriad of different systems and platforms can recognize. These names have to be unique so as not to create network confusion. (Considering that more than 10 million people access the Internet daily, and the number is growing steadily, this is of utmost importance.)

The Domain Name System (DNS) is what makes this network naming and access control possible. As TCP/IP has become the standard protocol suite for the Internet, DNS has become the convention for host naming. DNS is now available in some form or other (especially in its Berkeley Internet Name Domain, or BIND, implementation) in most TCP/IP-based software.

The beauty of DNS is its distributed maintenance. Donlain administrators have jurisdiction over their host names and yet cooperate with all other domain administrators over the Internet. Each domain keeps its own database stored on name servers organized in such a way that the data is always available. These servers are, again, distributed. No central authority has control — except, one might argue, the root servers that are the ultimate resources.

Another advantage of DNS is that the host naming structure is hierarchical, much like a typical directory structure in many filesystems, such as UNIX. This not only resolves any redundancy problems, it makes users aware that they’re part of a larger conceptual network of functionally similar hosts. These hosts may be in subzones and subdomains that serve particular needs and user communities.

DNS is often tricky. Special data types need to be maintained. There are special provisions for transferring this data from name server to name server. As a system manager, you may need to establish a subdomain for your set of hosts and register it with your parent domain administrator. You have to keep track of internet addresses as well as domain names.

The general purpose of DNS is to make your TCP/IP network run smoothly — and to make it expandable for the future.