Structure of the internet

Physical Structure

 Each continent has its own backbone of cables which connect to trans-continental cables which connect the internet together across the world. So everybody can access all of the same data.

National ISPs then connect to the backbone and distribute the internet to smaller providers which then distribute it to the people and homes.





Uniform Resource Locators (URL)

Full address of internet resources. Specifies the location of a resource on the internet, including the resource name, so that the browser can request it from the website server



Internet Registrars

Internet registrars hold databases of all the domain names that are currently available to purchase. These companies then act as resellers for the 5 main registries around the world. Companies and individuals can purchase them for use. The registries allocate IP addresses and keep track of which domain names is associated with as part of the Domain Name System (DNS).


Domain Names

Domain names represent the area or domain that the resource resides in. They work in a hierarchy format.

TLDS - Top Level Domain
FDQN - Fully qualified domain name is one that includes the host server name (www, mail or ftp).




IP Addresses

IP – Internet Protocol address is unique address, assigned to a network device. It indicates where a packet of data is to be sent or has been sent from. Routers can use this address to direct the data packet accordingly. 

E.g: 5.70.4.180 or 192.168.1.0

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