The Internet is a collection of networks. The very definition of internetworking is joining two different networks. The Internet is nothing more than a large internetwork.
That being said some terms need to be defined:
Network - In internet terms it is an ip network and mask (prefix...an IP network). This term can be very ambiguous. It's definition really depends on who you are speaking with. When speaking internet a network normally means - "a collection of hosts and systems that are under a single administrative control"
Host - An end node. A leaf on a tree. Nothing branches from here. A server. A PC. Something that sends and receives information via the same branch.
Router - a device that holds/maintains reachability information for various networks. Formost it sends data to where it needs to go. Think post office - a router sees that the destination is going to zip code 30221 and sends it to the post master who is in control of zip code 30221.
The concept of the post master has been carried over into the Internet. Even way back people knew how to efficiently deliver information. The "collection of hosts and systems that are undera single administrive control" is called an Autonomous System (AS). It is so called because it can fully function on it's own and is not affected by other systems. But mainly an AS defines administrative control.....a post master. Post master controls his zip code/state and is the authority on maintaining the accuracy of that information.
This just scratches the surface. But in very simple terms the Internet is nothing more than a large phone system. The host calls the other host, the host answer, the host asks for information.
That being said some terms need to be defined:
Network - In internet terms it is an ip network and mask (prefix...an IP network). This term can be very ambiguous. It's definition really depends on who you are speaking with. When speaking internet a network normally means - "a collection of hosts and systems that are under a single administrative control"
Host - An end node. A leaf on a tree. Nothing branches from here. A server. A PC. Something that sends and receives information via the same branch.
Router - a device that holds/maintains reachability information for various networks. Formost it sends data to where it needs to go. Think post office - a router sees that the destination is going to zip code 30221 and sends it to the post master who is in control of zip code 30221.
The concept of the post master has been carried over into the Internet. Even way back people knew how to efficiently deliver information. The "collection of hosts and systems that are undera single administrive control" is called an Autonomous System (AS). It is so called because it can fully function on it's own and is not affected by other systems. But mainly an AS defines administrative control.....a post master. Post master controls his zip code/state and is the authority on maintaining the accuracy of that information.
This just scratches the surface. But in very simple terms the Internet is nothing more than a large phone system. The host calls the other host, the host answer, the host asks for information.
