An Introduction to DNS

Abstract

The Internet—or any network for that matter—works by allocating a locally or globally unique IP address to every endpoint (host, server, router, interface, and so on). But without the ability to assign some corresponding name to each resource, every time we want to access a resource available on the network, the web site www.example.com for instance, it would be necessary to know its physical IP address, such as 192.168.34.166. With hundreds of million of hosts and more than 200 million web sites,¹ it’s an impossible task—it’s also pretty difficult with even a handful of hosts and resources.

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