Explain the following with reference to domain name system(DNS):

(1) DNS architecture

Name SERVERS are server programs, which hold information about the domain tree's structure and set information. A name server may cache structure or set information about any part of the domain tree, but in general a particular name name server has complete information about a subset of the domain space and pointers to other name servers that can be used to lead to information from any part of the domain tree

(2) DNS Zones

The zone, as indicated in the figure on the next page, is a subtree of the DNS that is administered separately. A name server can support multiple zones. Zones are contiguous regions of the name space, where each can be forked into sub zones. Each of these sub zones can have its independent management.