Networks

Learning Objectives

• Understand what a network is and the advantages and disadvantages

• Know the difference between wired and wireless networks

Networks• What is a Network?

• What hardware do you need to make one?

• What are the advantages and disadvantages of a network?

NetworksA network is two or more computers connected together so they can communicate which each other.

There are 2 main types of network…

Networks: LANsLAN stands for:

LOCAL AREA NETWORK

LANs are networks that are found where computers within a building need to communicate.

They are Small and Local!

Networks: WANsWAN stands for:

WIDE AREA NETWORK

WANs are networks that are found where computers in different areas or countries need to communicate.

They are long range and not local!

Networks: WANsWhat extra hardware do you need for a WAN network? •Modems : To connect up to

a telephone system (instead of cable).

How a modem works…

By the end of this section, you will

know and understand the hardware and

software involved in making a

network

• Main computer on the network.

• More powerful than other computers on the network.

• Contains a large amount of RAM and Hard Disk space.

• Holds the networks OS e.g. Windows XP

• Holds the application software e.g. Microsoft Office Suite.

• Stores the user files created on the system.

• Also known as NIC.

• Each computer MUST have one of these.

• It communicates with the file server and other computers on the network.

an RJ-45 NIC

• These plug into the back of each computer and link them together.

• They go straight into the Network Interface Card inside the computer.This is an RJ-45 cable, otherwise known as an

Ethernet Cable.

• A switch is a single connection point for a group of computers.

• The switch is then connected to the file server and organises the communication.

Wireless Router

Phone Line

Ethernet

Wireless Network

By the end of this section, you will

know and understand the

additional hardware and

software involved in making a WAN!

• Stands for Modulator – Demodulator.

• First created to take digital signals from a computer and convert them to analogue so that they can be transmitted down a telephone line.

• Speed at which a modem operates will affect the download time of web pages and files.

• An ISP sells Internet access to companies and individuals.

• It provides web servers which connect to the Internet.

• An ISP will provide it’s customers with a wide range of services…

• Bandwidth options.

• Email service.

• Web Hosting.

• Online and Telephone assistance.

• Browser software allows users to view and use the web pages on the Internet.

• Features include:• An Address Bar.

• A Navigation Bar.

• A Bookmark/Favourites Option.

• A Search Engine.

• A History Button.

• Browser Setting and Internet Options e.g. Filtering.

Networks:Some advantages of a network are:• Resources (Hardware and Software) can be shared.

• Allows more effective communication between users e.g. via e-mail.

• Networks are cheaper than “stand-alone PCs.”

• Information held on the network can be accessed by all users with authorised access.

Networks:Some disadvantages of a network are:• The set-up and maintenance costs can be expensive.

• A fault with the network server can cause difficulties with the organisation.

• Networks need security measures to restrict access to users.

• WANs are vulnerable to hackers and viruses.