Suggest an advantage and a disadvantage of running a caching-only DNS server at each host?
What will be an ideal response?
Since DNS servers cache the results from previous DNS requests, caching-only DNS servers may reduce the network traffic to a great extent. Whenever a DNS resolver tries to resolve a domain name, it contacts its local caching-only DNS server before contacting another DNS server. This not only results in faster domain-name/IP address resolution but also relieves the DNS servers, lying
up in the hierarchy, of catering to huge number of such requests from different hosts. And if an query entry is in a cache, the querying host get the fast response.
The disadvantage is that the caching has to be configured and enabled in all the DNS servers which creates a problem of maintainability. If the destination host changes IP address and cache has old IP address, they cannot communicate with each other
You might also like to view...
The Voronoi diagram for a set of K points in the plane is a partition of all the points of the plane into K regions, such that every point (of the plane) is assigned to the closest point among the K specified points. (See Figure 8.5.) What is the relationship between Voronoi diagrams and K-means clusters? What do Voronoi diagrams tell us about the possible shapes of K-means clusters?
The extension method ________ is used to filter the results of a LINQ query.
a. Filter b. Equals c. Where d. None of the above