WHAT IS DNS ?
DNS means Domain Name System
*ROLE OF DNS *
it converts the website name into ip address
PROXY used in DNS
REVERSE PROXY - Mid man between the client and the servers it distributes the request.
FORWARD PROXY - Multiple requests are converted into single request.
what is DNS resolver ?
A DNS resolver is a server that helps you find the IP address of a website.
** FLOW OF DNS RESOLVER**
USER - DNS QUERY INTIALIZATION - SUB RESOLVER (local machine internet cache DHCP) - RESOLVER - ISP (internet server provider it acts as a gateway between device and internet)
EXAMPLE
www.wikipedia.org.
here (.) - indicates the Root of DNS system.(even without the root the website can run )
org - indicates the top level domain it will point the secondary level domain when we ask for the ip address
wikipedia - idicates the secondary level domain holds the ip address
www - indicates the subdomain even without sub domain also the website can run.
how it works?
step 1 - Receives request from machine
step 2 - Checks if it already knows the answer like if we already search for it our machine has a memory of our search (cache) If not it will ask the:
Root of DNS system
TLD server
SLD server
Get the IP address
Hitback to our machine
Top comments (0)