Network Fundamentals

Study Notes

A network is a collection of interconnected devices that communicate with each other to share resources and exchange data.
Devices can be computers, servers, printers, routers, switches, and other hardware and software components.

LAN (Local Area Network): connects devices in a limited geographical area, such as a home, office, or building.
WAN (Wide Area Network): connects devices over a larger geographical area, such as a city or country.
MAN (Metropolitan Area Network): connects devices in a metropolitan area, such as a city or town.
WLAN (Wireless Local Area Network): connects devices wirelessly in a limited geographical area.
VPN (Virtual Private Network): connects devices securely over the internet as if they were on a private network.

Physical Topology: the physical arrangement of devices and connections in a network.
Logical Topology: the way data flows through a network.
Common Topologies:
- Bus: a single cable connects all devices.
- Star: devices connect to a central hub or switch.
- Ring: devices connect in a circular configuration.
- Mesh: each device connects to every other device.

TCP/IP (Transmission Control Protocol/Internet Protocol): the most widely used protocol suite for networking.
IP (Internet Protocol): responsible for addressing and routing data packets.
TCP (Transmission Control Protocol): ensures reliable data transfer.
UDP (User Datagram Protocol): used for fast, but not guaranteed, data transfer.

Hub: a simple device that connects multiple devices together.
Switch: a device that connects multiple devices and filters traffic based on MAC addresses.
Router: a device that connects multiple networks and routes traffic between them.
Gateway: a device that connects a network to another network or the internet.

Firewall: a device or software that blocks unauthorized access to a network.
Encryption: the process of converting data into a secure code to prevent unauthorized access.
Authentication: the process of verifying the identity of devices or users on a network.
Authorization: the process of determining what actions a device or user can perform on a network.

A network consists of interconnected devices that communicate to share resources and exchange data.
Devices in a network can include computers, servers, printers, routers, switches, and other hardware and software components.

LAN (Local Area Network) connects devices in a limited geographical area, such as a home, office, or building.
WAN (Wide Area Network) connects devices over a larger geographical area, such as a city or country.
MAN (Metropolitan Area Network) connects devices in a metropolitan area, such as a city or town.
WLAN (Wireless Local Area Network) connects devices wirelessly in a limited geographical area.
VPN (Virtual Private Network) connects devices securely over the internet as if they were on a private network.

Physical Topology refers to the physical arrangement of devices and connections in a network.
Logical Topology refers to the way data flows through a network.
Bus topology uses a single cable to connect all devices.
Star topology connects devices to a central hub or switch.
Ring topology connects devices in a circular configuration.
Mesh topology connects each device to every other device.

TCP/IP (Transmission Control Protocol/Internet Protocol) is the most widely used protocol suite for networking.
IP (Internet Protocol) is responsible for addressing and routing data packets.
TCP (Transmission Control Protocol) ensures reliable data transfer.
UDP (User Datagram Protocol) is used for fast, but not guaranteed, data transfer.

A Hub is a simple device that connects multiple devices together.
A Switch is a device that connects multiple devices and filters traffic based on MAC addresses.
A Router is a device that connects multiple networks and routes traffic between them.
A Gateway is a device that connects a network to another network or the internet.

A Firewall is a device or software that blocks unauthorized access to a network.
Encryption is the process of converting data into a secure code to prevent unauthorized access.
Authentication is the process of verifying the identity of devices or users on a network.
Authorization is the process of determining what actions a device or user can perform on a network.