Caching replies

While we are required to undergo this process for each new site we visit, if we had to do this for every site we revisit, it would be very cumbersome and slow.

Fortunately, the designers of DNS anticipated this and included a caching mechanism in the design of name servers. As a result, when we query a site for the first time, we would consult the root name server, then those for the 'au' domain, then the '' domain, then the '' domain etc. But as these answers are returned, our name server caches them, just in case we ask again anytime soon.

Of course, we do, and now, voila our query is so much quicker since most (if not all) of the time consuming DNS querying work has been done already. we'll talk about caches later in the module when we configure our name server.