Day 1 : Network Devices
A computer network is a digital telecommunication network which allows nodes to share resources.

Servers and Clients
Switches:
- have many network interfaces/ports for end hosts to connect to (usually 24+).
- provide connectivity to hosts within the same LAN (Local Area Network).
- do not provide connectivity between LANs/over the internet.
Routers:
- have fewer network interfaces than switches.
- are used to provide connectivity between LANs.
- are therefore used to send data over the internet.
Firewalls:
- monitor and control network traffic based on configured rules.
- can be placed “inside” the network, or “outside the network”.
- are known as “Next Generation Firewalls” when they include more modern and advanced filtering capabilities.
Host-based firewalls
- are software applications that filter traffic entering and exiting a host machine, like a PC.