assignment 2 1. wong mun sim, sylvia (s970588) group member :

Assignment 2

1. Wong Mun Sim, Sylvia (s970588)

Group member :

communications

computer

And networking

One computer can use the laser printer. The other computercan use the plotter. The hardware is not shared between users

Hardware sharing

The three computers can use both the plotter and the laser printer. The advantage of sharing hardware via networks

The two people can ‘talk’ by typing messages to each other

2. communication

Data sharing in a networking

3. Data sharing

Local area network (LAN)

Wide area network (WAN)

Type of network

1.

2.

1. Local area network (LAN)

A LAN links independent computers and other peripheral devices over short distances.

2. Wide area network (WAN)

A wide area network links computer systems over long distances.

Means of communication

1. Twisted-pair wire

2. Coaxial cable

3. Optical fibre

4. microwave

5. satellite

- It us typically used for telephone lines.

- A modem is needed for signal

- Telephone lines are designed for voice communication while computers use a digital signal.

Twisted-wire pair

modem

When two computers communicate to each other over a telephone lines, a modem is required for modulation and demodulation of signals.

Modulation : digital signals are converted to analogue signals

Demodulation : analogue signals are converted to digital signals.

- commonly used for LAN applications

- has greater capacity to transmit data.

Coaxial cable

- Both voice and data signals can be carried on the same line.

- data can travel very fast.

Optical fibre

microwave

- Data can be transmitted via microwave radio signals.

- The radio signal travels in a direct line from one relay station to the next.

Microwave transmission is limited by line-of-signt

satellite

Satellites are launched into space to relay data communication.

Three satellites can cover the Earth effectively

Communication software

Communication software is needed to enable computers with different configurations to send messages to each other

Novell network

A common communication software used in LAN is Novell.

Network topology

It describes how computers are connected together to form a network.

Three major network topology

1. Star network

2. Ring network

3. Bus network

Star network

Ring network

Bus network