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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)

TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7) 1 Name System Issues, Concepts and Techniques

Humans and computers first started dealing with each other several decades ago. The relationship between man (and woman!) and machine has been a pretty good one overall, and this is reflected in the fact that while computers were once just the province of techies, they are now mainstream. However, there are areas where humans and computers simply don't see eye to eye. One of these is in the way that we deal with information.

Computers work best with numbers, while most people prefer… not to work with numbers. This fundamental disconnect represented a problem for the designers of networking technology. It made sense from a technical standpoint to design addressing schemes for networks and internetworks using simple numeric identifiers, for simplicity and efficiency. Unfortunately, identifying computers using numeric addresses is cumbersome for people, and becomes more so as the number of devices on a network increases.

To solve this problem, the techies went to work, and came up with name systems for networks. These mechanisms allow computers to continue to use simple, efficient numeric addresses, while letting humans specify easier-to-remember names that identify them. This way, everyone is happy. Well, almost everyone I guess. These systems mean those of us studying networks have one more thing to learn. J

In this section I explain both the theory and practice behind networking name systems. I begin with a section that describes the motivation for name systems and the important concepts and techniques behind how they work. I then have a large section devoted to the name systems used for TCP/IP. This includes both the very important Domain Name System (DNS), as well as the older host table method that preceded it.

TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7) 1 Name System Issues, Concepts and Techniques