Computer Networks - lecture2Application Layer and DNS

servers root hints dns server computer1 com company1

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Unformatted text preview: S Server Computer1 com Company1 How Iterative Queries Work An iterative query is a query made to a DNS server in which the DNS client An requests the best answer that the DNS server can provide without seeking further help from other DNS servers. The result of an iterative query is often a referral to another DNS server lower in the DNS tree Iterative Query Rec mai ursive l1.co que mpa ry fo ny1 r .com 172 .16. 64.1 1 Local DNS Server Computer1 Computer1 Root Hint (.) Ask .com 1 Iterative Query As compa k ny1.co 2 m Itera tive Que Auth ry orita tive R espo nse .com 3 nwtraders.com How Forwarders Work A forwarder is a DNS server designated by other internal DNS servers to forward queries for resolving external or offsite DNS domain names Iterative Query Re cu r s iv eQ ue ry 172 .16 .64 .11 Forwarder 172.1 6. Local DNS Server 64.11 Recu r mail1 sive quer y .com pany for 1.com Ask .com Iterative Q u e ry Ask co mpany 1.com Itera tive Que Auth ry orita ti ve R espo nse Root Hint (.) .com company1.com Computer1 How DNS Server...
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This note was uploaded on 10/15/2011 for the course COMPUTER E EC-321 taught by Professor Liaqatali during the Spring '11 term at College of E&ME, NUST.

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