A local area network (LAN) is a group of computers and associated devices that share a common communications line and typically share the resources of a single processor or server within a small geographic area (for example, within an office building). Usually, the server has applications and data storage that are shared in common by multiple computer users.


However, while a  local area network may serve as few as two or three users , it could also serve thousands of users

Ground Station:  By Ground station we are referring to the VSAT( Very Small Aperture terminal) and its router which  receive from and transmit data to satellites. As explained earlier, this could be owned by an ISP from which an internet user or network of users could gain access via phone lines and modems or could be owned by an institution or organization itself.

Groundstation

Hub: A hub is  a Collection of communications equipment designed to receive signals from (and usually transmit signals to) satellites. It is also called a downlink station

A Hub
A Satellite Service Provider is a company which provides a basic link  to the internet via a satellite, ie, they own a hub  In some cases, Satellite service Providers serve Internet Service Provider ( ISP's) with a connection to the internet. However, ISP's can generally hook up to the internet backbone via several other means like fibres, copper telephones, etc. depending on their location and access to the backbone.

An Internet Service Provider (ISP)  is an Organization that provides one or more basic internet services such as Internet access, web site hosting, or DNS support for domains . ISP's provide information  to  their customers (internet users) directly via phone lines and to networks via routers as depicted below.


In this case our ISP not only provides internet access to its individual customers but through a hub at the organization  or company, it can provide services to a network of computers. The whole picture of how internet access via an  ISP works is as depicted below

Internet backbone


Generally when we mention the term internet backbone, we are referring to the main pipes along which data is transferred; the central data transmission lines. The backbone is not operated by any one company or government though  companies operate components of the Internet backbone.)