Network Fundamentals

Study Notes

A computer network is a collection of interconnected devices that communicate with each other to share resources and exchange data.
Networks can be classified into three types:
1. LAN (Local Area Network): connects devices in a limited geographical area, such as a home, office building, or campus.
2. MAN (Metropolitan Area Network): spans a larger geographical area, such as a city or town.
3. WAN (Wide Area Network): covers a large geographical area, such as a country or continent.

Physical Topology: The physical arrangement of devices in a network, including:
- Bus: a single cable connects all devices.
- Star: devices connected to a central hub or switch.
- Ring: devices connected in a circular configuration.
- Mesh: each device connected to every other device.
Logical Topology: The way data flows through the network, including:
- Peer-to-Peer: devices act as both clients and servers.
- Client-Server: devices act as either clients or servers.

TCP/IP (Transmission Control Protocol/Internet Protocol): the most widely used protocol suite, consisting of:
- TCP (Transmission Control Protocol): ensures reliable, error-checked data transfer.
- IP (Internet Protocol): provides logical addressing and routing.
HTTP (Hypertext Transfer Protocol): a protocol for transferring data over the internet.
FTP (File Transfer Protocol): a protocol for transferring files over a network.

Hub: a simple network device that connects multiple devices together.
Switch: an intelligent device that connects multiple devices and filters traffic.
Router: a device that connects multiple networks and routes traffic between them.
Gateway: a device that connects multiple networks and routes traffic between them, often used to connect to the internet.

Firewall: a system that controls incoming and outgoing network traffic based on security rules.
Encryption: the process of converting data into a coded format to prevent unauthorized access.
Authentication: the process of verifying the identity of devices or users on a network.

A computer network is a collection of interconnected devices that communicate with each other to share resources and exchange data.
Networks can be classified into three types: LAN, MAN, and WAN.
LAN connects devices in a limited geographical area, such as a home, office building, or campus.
MAN spans a larger geographical area, such as a city or town.
WAN covers a large geographical area, such as a country or continent.

The physical arrangement of devices in a network, including:
- Bus topology: a single cable connects all devices.
- Star topology: devices connected to a central hub or switch.
- Ring topology: devices connected in a circular configuration.
- Mesh topology: each device connected to every other device.

The way data flows through the network, including:
- Peer-to-Peer topology: devices act as both clients and servers.
- Client-Server topology: devices act as either clients or servers.

TCP/IP is the most widely used protocol suite, consisting of:
- TCP: ensures reliable, error-checked data transfer.
- IP: provides logical addressing and routing.
HTTP is a protocol for transferring data over the internet.
FTP is a protocol for transferring files over a network.

Hub: a simple network device that connects multiple devices together.
Switch: an intelligent device that connects multiple devices and filters traffic.
Router: a device that connects multiple networks and routes traffic between them.
Gateway: a device that connects multiple networks and routes traffic between them, often used to connect to the internet.

Firewall: a system that controls incoming and outgoing network traffic based on security rules.
Encryption: the process of converting data into a coded format to prevent unauthorized access.
Authentication: the process of verifying the identity of devices or users on a network.