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Resolvers in client software such as a web browser, are not designed to hunt down answers about hosts and domains on their own. They rely on the local DNS server to do this for them. For this systemof having client software relying on a DNS server to work, a recursive DNS server must be available for these clients.
An Iterative DNS query results in a single DNS server being queried, and only getting a single response. If the DNS server has the answer, it sends it. If not it sends a "host/domain not found" error message, but the DNS server does not do any additional resolution. It does not query any other DNS servers.
Because recursive lookup takes the DNS server longer and requires more memory to store records, it sometimes is more efficient to separate the DNS services for external (internet) users from the internal (LAN) users. To do this, a recursive DNS server is provided for the internal users, and a non-recursive or 'iterative' server is provided for Internet users to enable them to resolve ONLY your domain.
A Domain Name Server which provides for iterative lookup performs resolution using the information within it's own lookup tables. It does not query other name servers for information. When a client request is sent to the server, it searches it's local database, and if it has an answer, it will reply. If it does not have an answer, it will respond with a 'host not found' message.
Iterative servers are useful when you wish to provide resolution for your own zone, and only your zone. All users pointed at this server to fail to resolve anything not entered on the DNS server. This restricts the nameserver to responding for only information stored on it, and thus is useless for resolving anything else. This decreases the usefulness of the machine for any other purpose than resolving your domain, and will speed up DNS resolution to some degree as well.
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What is the limitation and advantages of iterative model of sdlc?
In iterative model we get an end product at the end of each iteration. Iterative model is not so efficient and time consuming.
Does host computers typicall use iterative queries?
do host computers typicall use iterative queries
When you choose iterative or recursive algorithm?
If you cannot find any iterative algorithm for the problem, you have to settle for a recursive one.
Is the design process iterative?
yes
What is the advantage of the iterative method?
non
What are iterative statements?
An iterative statement is a looping statement, such as a 'for', 'while', or 'do-while' statement. They cause statements to be repeated (iterated) multiple times.
What is the iterative waterfall?
Iterative waterfall model is a software process model also called the incremental process model. http://en.wikipedia.org/wiki/Iterative_and_incremental_development
Which process model suitable for development project?
Iterative
What has the author I Sharf written?
I. Sharf has written: 'An iterative approach to multibody simulation dynamics suitable for parallel implementation' -- subject(s): Iterative solution, Multibody systems
What do we mean by iterative approximation of the fixed point?
An iterative approximation of a fixed point is a number, say x, that has been obtained through the use of an iterative method. x is called a fixed point of a function if and only if the function equals x when evaluated at x i.e. when f(x)=x.
What is difference between agile model and iterative model?
nothing
What is the first number in an iterative equation called?
The first number you use in an iterative equation/method is known as the initial point and is often symbolised with a subscript 0 like so, x0.
