LAN — local area network, single farm connected through wires. (Not a server farm)
MAN — Metropolitan area network. When a city or area is connected through internet connection.
WAN- Wide Area Network is when a country or the whole world is connected together.
Topology of a network
Mesh: two way connections in between nodes. It is complex
bus: Single wire shared by multiple computers. If there is a disturbance the whole network gets disturbed.
star: If one device crashes it doesn’t crash the whole system.
ring: Connected in a circular fashion. Passes tokens between devices. If any devices crash then the whole network gets destroyed.
Networking Devices
Routers: They help in routing, create a path. It is an IP resolver.
hub: provides half duplex communications.
Switch: provides full duplex communication. It is intelligent because it allows two way communication.
Bridges: Helps my computer and the network connect to each other. It creates a path.
Firewalls: Lets some information in and keeps other information out. Accept information (allowing traffic), reject information (blocking trafic and reporting) or drop information (blocking traffic without giving a message).
Gateways: Helps block unnecessary data that will come and hamper your system.
Servers
OSI: Open system interconnection. First ever structur for web communication between any two devices. There are 7 layers.
7 server layers.
A network engineer will work on the layers 2–7.
Application layer: produces data.
Presentation Layer: Translation layer. Encrypts and decrypts.
