We all know that in the world of domain names today, the presence of the
DNS domain name system is very much significant. It is interesting to know that the acronym
DNS actually stands for Domain Name System/Service/Server. However, I will be using the term
DNS domain name system here to provide you with a clear knowledge about the meaning of this
The DNS domain name system is actually a powerful tool that contributes a great part in the
domain name process. It is often described as an internet service that translates or transforms
the domain names into an IP or Internet Protocol address.
Aside from knowing such basic function of the DNS domain name system, it is also interesting
to learn that a basic possession of the DNS domain name system is caching. This property takes
place in situations when a server welcomes information about a mapping, it caches that information.
Therefore, with such function, a later question for similar mapping can use the cached output,
and will not result to additional questions to other servers. And generally,
the DNS domain name system applies the caching to optimize the cost of the search.
But how does the DNS domain name system caching works?
In terms of caching, it is very nice to know that every server has a cache for currently
applied names along with records of where the mapping data for a particular name was taken.
So when a particular client is asking the server to determine a certain domain name,
the DNS domain name system then does check if it has the power for a domain name, and if it does,
the system doesn’t need to cache the information. However, if it has no authority for a
domain name, the DNS domain name system then checks its cache whether the domain name has
been resolved currently, and if yes, the DNS domain name system reports the caching data to
There are some instances that the DNS domain name system cache can be examined when the system
cached the data once, but didn’t adjust it. Due to the reason that the information about a
certain domain name can be changed, the server may have inaccurate data in its caching table.
There is a certain value known as the Time to Live or known as TTL which is applied when to age
the information. So whenever an authority responds to a request for a domain name,
it then involves a Time to Live value in the answer which indicates how long it assures the
binding to linger.