Pre-Computer Skills Internet 1. General Concepts Internet A system of connected computers that...

27
Pre-Computer Skills Internet 1

Transcript of Pre-Computer Skills Internet 1. General Concepts Internet A system of connected computers that...

Pre-Computer Skills

Internet

1

General Concepts

• Internet

A system of connected computers that allows your computer to exchange data, messages and files with any of the millions of other connected computers.

• World Wide Web (www)

A collection of Web pages and related resources which are linked together across the Internet

2

General Concepts

• IntranetA private network that is contained within an enterprise, and used to share company information among employees.

• Extranet

A private network that uses Internet technology to share part of business information with suppliers, partners, customers or other businesses.

3

General Concepts

• HyperlinkA piece of text that can perform an action when the users clicks on it.

• Web BrowsersAre computer programs that allow people to access information on the World Wide Web (WWW), e.g. Microsoft Internet Explorer and Netscape Navigator

4

General Concepts

• Web SiteA computer storage area that contains one or more Web pages.

• Home PageThe first Web page you see when you launch Internet Explorer.

• Uniform Resource Location (URL)A unique address given to every web page

5

General Concepts

• Protocol A set of instructions for transferring data

between computers over the network

• Site Map or Site Indexis similar to a table of contents in a book; it tells you where you can find information by category.

• Internet Service Provider (ISP)A company that offers their customers access to the Internet

6

General Concepts

• Hyper Text Markup Language (HTML)A set of formatting commands that you place around a text or pictures to create a Web page.

7

Internet ConnectionServices

There are different Internet connection

services, such as:• Dial-UP Connection:

– Early days of the Internet– Computer Modem Phone Line– To connect, user should dial up the ISP.– Disadvantages:

• Very slow• To make a phone call, you should disconnect the

Internet.8

Internet ConnectionServices

• BroadBand Connection:– Permanent connection to the internet– No need to disconnect to make a phone call– Immediate access to your email– Fast service– Paid on monthly basis, not by seconds.

9

Options for Internet Connection

• Phone Line– Most common option

– Uses your phone line for connection

– It needs a computer, a modem, a phone and an account with an ISP.

• The mobile phone– Wireless Technology

– Uses the existing cellular telephone networks

– Available anywhere there is a cellular coverage

– Portable and perfect for traveling10

Options for Internet Connection

• Satellite– Delivers the Internet via satellite dish– Speed quite high– Requires special equipment– High cost

• Wireless Hot Spots– Wireless and high speed Internet connections– Often provided in airports, hotels, cafes, shopping

centers and restaurants– Free for web browsing, but no downloading permitted.

11

Characteristics of BroadBand

• Fast connection to the Internet– Rapid loading of web pages– Fast downloading of files and attachments– Ability to talk to others (audio and video

chatting) and attend video conferences at real time

• An Always-On connection– Available 24 hours

12

Characteristics of BroadBand

• Flat Fee Payment– Cost depends on the speed of the service you

require, and the amount of downloads and uploads

• Risk of Intruder Attack– Your computer is in constant contact, which enable

hackers to invade your computer connection– Anti-virus programs should be up-to-date– Firewalls are need to prevent unauthorized external

users from accessing the system.

13

Security Consideration

• Identification ( المستخدم هوية (تحديد– A User ID is used to logon to a computer or a

computer network. It uniquely identifies you to the network

• Authorization ( التوثيق - المستخدم هوية (اثبات– A proof that the user is authorized, either a signature

or a password.

• Authentication ( - المستخدم صالحيات تحديد(التفويض– Specifies the privileges given to users to access

certain resources or data.14

Security Considerations – Password Policies

• Passwords: are secret words or numbers that must be keyed into a computer system to gain access.

• To make a password more effective:– Do not share it with others– Change it regularly– Choose your password from a combination of

letters and numbers that are difficult to be guessed by others.

15

Security ConsiderationsData Security

• Data Security: is a system of safeguards for protecting information technology against disasters, system failure, or unauthorized access that can result in damage or loss.

16

Security ConsiderationsBackups

• They are copies of all software, files and information which you have in your computer systems. You can use those copies when the original copies are damaged because of physical failure, user errors, accidents or carelessness.

17

Security ConsiderationsFirewall

• A Firewall, is a set of related programs located at a network server that protects the resources of a private network from users from other networks

18

Security ConsiderationsViruses

• Viruses are software programs which are written with the intention of causing inconvenience and disruption or serious damage in a computer system. Files on floppies can spread viruses across a network or via email and the internet.

• There are several types of viruses, some targets specific types of files, others targets the main memory, and others effect the booting of the computer system.

19

Security ConsiderationsHow can Viruses enter a computer

system

• Viruses hide on disks. When you access the disk, the virus will infect your computer. It then can spread from one computer to another. When you connect to Internet, you have to make sure that AntiVirus programs are working and are updated.

20

Security ConsiderationsIndicators of Virus infection

• There are some indicators that show you that your computer might be infected by a virus, such as:– When it runs slower than normal– When it crashes and restarts every few

minutes– It restarts on its own and then fails to run

normally– When you see unusual error messages

21

Security ConsiderationsProtection against viruses

• To protect your computer against viruses, do the following:– Use a high-quality anti-virus program such as (Norton

and McAfee), and be sure to update it regularly– Always scan your disks and files after using them on

other computers– Always scan the files you download from the Internet.

The same applies to attachments downloaded from e-mails

– Make back-up copies of important documents or files and store them on separate disk

22

Security ConsiderationsIllegal Access

• Illegal access to the computer information includes copying, modification and locking of the data on the single computer, computer systems and networks. The main object of the illegal access to the computer information is reaching the owner’s information and invading his or her privacy right.

23

Security ConsiderationsIllegal Access

• Illegal access may cause the following:– The web site is deleted, modified or corrupted– Corporate networks will end up experiencing virus

attacks– You will receive email threats– Your mail will become available to an

unauthorized party– Others will own your private information– Modifications or corruption of the data bases and

documents24

Security ConsiderationsHacking

• Hackers are people who create or improve programs and share them with fellow hackers to gain unauthorized access to computer systems.

25

Security ConsiderationsPassword Cracker

• Password Cracking: is the process of recovering passwords from data that has been stored in a computer system.

• A common approach is to repeatedly try to guess the password.

• The purpose of password cracking:– Help a user recover a forgotten password – Gain unauthorized access to a system– Check for easily cracked passwords (Used by

administrators)26

Security ConsiderationsEncryption and Decryption

• Encryption: is the conversion of data into a form that cannot be easily understood by unauthorized people.

• Decryption: is the process of converting encrypted data back into its original form, so it can be understood. In order to do that, a correct decryption key is required.

27