This document discusses various aspects of computer networks including network topologies like bus, star, ring and mesh. It also covers network scales such as LAN, MAN, PAN and WAN. The different network nodes including NIC, router, modem, repeater, hub, bridges, switches and firewall are defined. Finally, the document touches on network security measures taken by organizations to secure their network and data using both hardware and software systems. It also briefly lists some wired network types such as coaxial, twisted pair and optical fiber as well as wireless communication methods like microwave, radio waves and communication satellites.

1. Computer
Networks
Network Topology
1
. Bus
2.Star
3.Ring
4.Mesh
5.Tree
Types on
Scale
1. LAN. 2.MAN
3.PAN. 4.WAn
............
Network
Nodes
1.NIC
2.Router
3.Modem
4. Reapeater
and Hub
5. Bridges and
Switches
6. Firewall
Network Security
refers to the
measures taken by
any enterprise or
organization to
secure its
computer network
and data using
both hardware and
software systems.
Wired
Networks
1.Coaxial
2.Twisted pair
3.Optical fibre
Wireless
communication
1.Micro wave
2.Radio wave
3.Communication
satellite
etc.