Introduction to CCNA Course by Jeremy's IT Lab

Initial Lessons: Network Devices

• Symbols and functions in a network.
• Network Definition:
  • A network is a digital communications network which allows nodes to share resources
  • Nodes include devices like routers, switches, firewalls, servers, clients.

Types of Network Devices

• Router:
  • Directs data across networks.
  • Connects different LANs and to the Internet.
• Switch:
  • Connects devices within a LAN.
  • Many ports for end hosts.
• Firewall:
  • Protects network by filtering traffic.
  • Available as hardware (network firewall) and software (host-based firewall).
• Server:
  • Provides services to clients.
  • Can be any device including personal computers.
• Client:
  • Accesses services provided by servers.
  • Can be various devices like PCs, smartphones.

Network Construction Example

• A simple network: Two PCs connected by a cable form a basic network.
• Network Clients: Example devices include Windows PCs, Macs, iOS devices.

Client-Server Model

• Client: Device accessing a service.
• Server: Device providing a service.
• Examples:
  • PC requesting a file from another PC.
  • Smartphone requesting video from a server.

Extending the Network

• Enterprise Network Example:
  • Branches in New York and Tokyo.
  • Uses switches for many local connections.
  • Routers connect LANs and the Internet.