YEAR 1 CO1 WEEK 23 DNS

Question 1

What is the Internet?

Answer 1

A collection of computer networks connected together.
To join need to have every device a unique IP address.

Question 2

What is an IP address and what does it contain?

Answer 2

It is a numerical address which uniquely identifies devices on a network. Allocated to software rather than hardware used to route data across WANs.
Contains address of network + address of node within network.

Question 3

Describe Static IP address.

Answer 3

If you own public website IP address of server should never change. Otherwise hard for people to find.

Question 4

Describe Dynamic IP address.

Answer 4

When device temp connected to Internet dynamic IP address allocated.
When device disconnects IP address available for use for another device.

Question 5

Describe what an ISP is.

Answer 5

ISP a company that provides access to the Internet.
Issue you with a router, username + password and email address.

Question 6

Describe what DNS is.

Answer 6

When URL typed in Web browser will query a DNS.
The DNS has databases of all domain names + the associated IP addresses.

Question 7

Describe the process of the DNS.

Answer 7

DNS used to resolve IP addresses to corresponding URL.
Request sent to DNS resolver.
Resolver checks it’s cache to see it in memory.
If not passes to TLD Name Server which checks cache else passes to Authoratative Name Server.
IP address returned back to requesting client else error if no resolution found.

Question 8

State advantages of DNS.

Answer 8

Do not need to remember IP addresses.
As long as connected to DNS have access to all addresses.