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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  Name Systems and TCP/IP Name Registration and Name Resolution            9  Name System Issues, Concepts and Techniques

Name Registration Methods, Administration and Authorities 1 2 Efficiency, Reliability and Other Name Resolution Issues and Features

Client/Server Resolution Functional Elements

The last of these three methods is the one used for most large, modern name systems. The client/server method of request/reply resolution is similar to how many other protocols function. One thing that is unique about name resolution, however, is that name resolution isn't often invoked directly by the client. It's rare, for example, for a human user to say “please resolve the following name”. We also certainly wouldn't want a user to have to manually resolve a name to an address each time they wished to contact a device, as this would be cumbersome.

Instead, the system is automated by having software accept machine names input by users. The software resolves the name by passing it to a name resolver software component. The resolver acts as the client in the name resolution process. It contacts a name server, which responds to the request. The name resolver and name server constitute the two main functional elements in name resolution.

In a distributed database for a hierarchical name system, multiple requests may be required, since name servers will contain only information for certain machines and not others. Resolvers follow a special procedure to “travel” the hierarchy until they find the server that has the information they want. Again, TCP/IP's Domain Name System (DNS) name resolution is the best example of this method.

Name Registration Methods, Administration and Authorities 1 2 Efficiency, Reliability and Other Name Resolution Issues and Features