DNSs Flashcards
What does DNS stand for?
domain name system
Why do we have domain names?
to easily remember the IP addresses of websites and resources (using alphanumeric values)
What is a DNS?
- a conversion carried out by domain name server to unique IP addresses of resource
- converts a domain name into a unique IP address
- it identifies the area or domain the resource resides in
- it is used to register new domains and ensure they’re unique
How are DNS structured and what they’re governed?
structured in to a hierarchy of smaller domains separated by full stops as dictated by the rules of the domain name system
Some top level domains?
- .com
- .edu
- .org
- .uk
- .fr
Some 2nd level domains?
- .co
- .gov
- .sch
Some 3rd level domains?
- .bbc
- .ebay
- .lidl
What does each domain name has?
equivalent IP addresses
What happens when a webpage is requested using a URL?
the browser requests the corresponding IP address from a local DNS.
If the DNS doesn’t have the correct IP address, the search is extended to a hierachy to another larger DNS database.
When located the resource is sent and data request is sent by user’s computer to that location to find the webapge.
What carries out the actual conversion?
The domain name server