Computer Network

Computer Network

Computer Network • A Computer Network is a communication system that connect tow or more computers so they can exchange information and share resources. • the most well-known computer network is the Internet .

Benefits of Computer Networks

Benefits of Computer Networks • Exchanging Information • Sharing of resources: • Software • hardware

CLASSIFICATION OF NETWORKS: • Computer networks are classified into different types, based on the following: • According to the network's Transport Media (Wired and Wireless) • According to the network's Geographical Area (PAN, LAN, MAN and WAN) • According to the network's Management System (Peer to Peer, Client – Server)

Types Of NetworksAccording to Transport Media • Wired Networks • Wireless Networks

Types Of NetworksAccording to Geographical Area: • personal area network (PAN)

Types Of NetworksAccording to Geographical Area: • Local Area Network (LAN) • A local area network (LAN) is a computers network that interconnects computers within a limited area such as school, university or office building. LAN can span over a limited distance up to one mile.

Types Of NetworksAccording to Geographical Area: • Metropolitan Area Network (MAN) These networks are considered larger than LAN as they connect several LANs in the same city and are usually used to connect organizations, companies, banks and government agencies. MAN can span over a distance up to 100 miles

Types Of NetworksAccording to Geographical Area: • Wide Area Network (WAN) • Wide area network (WAN) is a countrywide or worldwide network, which covers distances greater than 100 miles. It uses microwave relays and satellites to reach users over long distances. The widest of all WANs is the Internet, which spans the entire globe.

Types Of NetworksAccording to the network's Management System • Client-Server Network

Types Of NetworksAccording to the network's Management System • Client-Server Network Client-server network systems use one computer (server) to coordinate and supply services to other computers (clients) in the network. The server provides access to resources such as web pages, databases, application software, and hardware.

Types Of NetworksAccording to the network's Management System Peer-to-Peer Network

Types Of NetworksAccording to the network's Management System Peer-to-Peer Network A peer-to-peer network system doesn't have a central computer (server). All nodes have equal authority and can act both as clients and servers. For example, when a file passes through many computers on a network, these computers act as both server and client.

Internet • Internet is a huge network of computer networks. The Internet can be termed as a network of • networks. The Internet is the global network • system of private, public, academic, business and government networks.

USES OF THE INTERNET • AS A SOURCE OF INFORMATION • SHOPPING • ENTERTAINMENT • Education • communication

INFORMATION SECURITY

The password: A Password is a set of characters used to get access to a computer, web page, network resource or data TIPS FOR CREATING PASSWORDS Creating a strong password is the responsibility of the owner. Below are the recommendations for creating a strong password: • The password should be difficult to guess. • The password should not be less than the length of 8 characters. • The password should contain a mixture of numbers, characters • The password should not contain the user's name. • The password should not contain the user's personal information, as name, street address, phone number, date of birth etc.

The password: TIPS FOR THE USE OF PASSWORD •Do not share your passwords with others. •Do not use the same password everywhere such as e-mail, bank account … •Do not keep a written record of passwords on a paper or in an e-mail •Avoid using the "Remember Password" option everywhere.

MALICIOUS SOFTWARE • Malicious software, also known as Malware, is any program or file that is harmful to a computer or the privacy of users. The harm done by malware can vary from something slight as changing the author's name on a document to full access of your machine

TYPES OF MALICIOUS PROGRAMS • Malware types can be categorized as follows: • • Viruses • • Worms • • Spywares • • Trojan Horse

Viruses A computer virus is a malicious program that attaches itself to a file or a program, enabling it to spread and infect different files. Viruses can be transmitted as attachments to an e-mail or in a downloaded file. Viruses are attached to an executable file, which means the virus may exist on a system but will not be active or able to spread until a user runs or opens the malicious host file or program

Worms Worms are stand alone malicious software and do not require a host program or human help to spread. It replicates its functional copies and can consume system memory.

Spywares Spyware is classified as privacy-invasive software. The most common spyware function is to steal personal information and address book

Trojan Horse A Trojan is another type of malware. It is a harmful piece of software that looks genuine. Users are typically tricked into loading and executing it on their systems. After it is activated, it can achieve any number of attacks on the host, from irritating the user (popping up windows or changing desktops) to damaging the host (deleting files or activating and spreading other malware). Trojans are also known to create back doors to give malicious user access to the system.

To stay protected from malicious software: •Avoid using the "auto-run" option in Windows OS for portable drives. •Use anti-spyware software, anti-virus software and scan and update regularly. •always be wary of strange e-mails, especially ones with attachments. •While browsing the Internet, always confirm what you click , download and install.

THE BACKUP • Local Backup • Internet Backup (Cloud Storage) • EX : Drop Box , Google Drive and One Drive

Computer Network