1. Network Classification

2. 4.1 Network Fundamentals
why network is needed?
The need to share information and resources among different computers has led to linked computers systems, called networks, in which computers are connected so that data can be transferred form machine to machine. In these networks, computer users can exchange messages and share resources-such as printing capabilities and data storage facilities-that are scattered throughout the system.

3. 4.1 Network Fundamentals
The underlying software required to support such applications : simple utility package  an expanding system of network software that provides a sophisticated network-wide infrastructure (in a sense evolve into a network-wide operating system).

4. 4.1 Network Fundamentals
network classification (1)
A computer network is often classified as being either a local area network (LAN), a metropolitan area network (MAN), or a wide area network (WAN).
A LAN normally consists of a collection of computers in a single building or building complex (the computers on a university campus or those in a manufacturing plant).

5. 4.1 Network Fundamentals
network classification (1)
A computer network is often classified as being either a local area network (LAN), a metropolitan area network (MAN), or a wide area network (WAN).
A LAN normally consists of a collection of computers in a single building or building complex (the computers on a university campus or those in a manufacturing plant).

6. 4.1 Network Fundamentals A MAN (spanning a local community)
A WAN (in neighboring cities or on opposite sides of the world)

7. 4.1 Network Fundamentals
Network Classifications: (2)
Another way of classifying networks is based on the topology of the network, which refers to the pattern in which the machines are connected.
Bus and star are two of the more popular topologies

8. 4.1 Network Fundamentals
The bus topology was popularized in the 1990s when it was implemented under a set of standards known as Ethernet, and Ethernet networks remain one of the most popular networking systems in use today.
Star: in which one machine serves as a center focal point to which all the others are connected.

9. Figure 4.1 Network topologies

10. Figure 4.1 Network topologies (continued)

11. 4.1 Network Fundamentals Summary why network is need?
network classification