OVERVIEW OF THE INTERNET

ARPANET

• ARPA - Advance Research Project Agency created by US Department of Defense.
• The network is called ARPANET
• The network became functional in September 1969 
• The Internet originated as ARPANET and had two main goals.

            1. Allow scientist at different physical locations to share information and work together.\

            2. Function even if part of the network were disabled or destroyed by a disaster (nuclear ttack)

•  The original ARPANET consisted of 4 main computers located at: 

a. UNIVERSITY OF CALIFORNIA at Los Angeles.

b. UNIVERSITY OF CALIFORNIA AT Santa Barbara.

c. THE STANFORD RESEARCH INSTITUTE

D. UNIVERSITY OF UTAH

INTERNET2

• Internet2 is not a new network ( especially to replace the internet)
• It is a Research and Development (R&D) project.
• In developing technology to ensure that the internet in the future can handle tomorrow's applications.
• Not-for-profit R&D project.
• Connects more than 200 universities and 115 companies via a high- speed private network.

WHO CONTROLS THE INTERNET

↬ NO ONE-  It is a public, cooperative and independent network.

 Several organizations set standards

• example of organization:

→ establishing the protcols used on the Internet.

→making recommedations for changes.

→encourage cooperation between the coordinating communications among the networks connected to the Internet.

ADVANTAGES

⇰Software Downloads:

  you can freely download software like utilities, games, music, videos, games, movies etc from the Internet.

⇰ Online Services
￫ perform all your transactions online.
￫ can book tickets for a movie, transfer funds, pay utility bills.
￫ make a hotel or flight reservation right from your home.

⇰ E-mail
￫ people can sent messages. it is delivered instantly to people anywhere in the world, unlike traditional mail that takes a lot of time.

⇰Information resources
￫can find any information on almost any kind of subject that you are looking for by using search engines like Google, Yahoo, MSN, etc


DISADVANTAGES

⇰Virus treat
⇁computers atached to internet are more prone to virus attackes and they can end up into crashing your whole hard disk.

⇰Social disconnect
⇁ people can now only meet on social networks
⇁ more and more people are getting engaged with virtual world and drifting apart from their friends and family.

⇰Dangers involved when children using the Internet
⇁ When children talk to others online, they do not realize they could actually be talking to a harmful person. plus, there are thousands of pornographic sites on the Internet that could be easily found.

⇰Theft of personal information
⇁ your personal information such as name , address, credit card, bank details and other information can be accessed by an irresponsible people for their own benefit.


INTRANET

• An intranet (intra means within) is an internal network that uses internet technologies.
• Network which only available inside an organizations or a company.
• Intranet generally make company information accessible to employees and facilitate working in groups.
• Simple intranet applications include electronic publishing of organization material such as telephone directories, event calendars and employee benefits information

ADVANTAGES

⇒ Commercial or confidential data is kept  secure within the organization

⇒Email remain private and may also be encrypted

⇒High bandwidth. No connection lmits unlike the Internet.

⇒Reliable. The company will have dedicated it personnel to keep things running smoothly.

DISADVANTAGES

↪ High financial cost incurred by the company when initially implementing the intranet.

↪Connections between an intranet and the Internet potentially compromises security , by allowing virus infections or system hacking.

↪Staff needs training to ensure  workers kno how to use the system effectively.

↪Information overload is another disadvantage because it reduces productivity.

EXTRANET

• An extranet is the portion of  company's network that allows customers or suppliers of a company to access parts of an enterprise's intranet.
• An extranet provides a secure, physical connection the company's network.

ADVANTAGES

↣Exchange large volumes of data using electronic data interchange (EDI)
↣Share product catalogs exclusively with trade partners.
↣Collaborate with other companies on joint development efforts.
↣Jointly develop and use training programs with other companies.

DISADVANTAGES
↝Extranet can be expensive to implement and maintain within an organization(e.g., hardware, software, employee training costs), if hosted internally rather than by an application service provider.
↝Security of extranets can be a concerm when hosting valuable or proprietary information.