Unit 3: Communications, Networks and Internet

Alexa C. Year 10Unit 3: Communications, Networks and InternetCommunicationCommunication has revolutionized the way that businesses work and has enhanced everyday life.Communication MethodsWays we communicate:TelephoneE-mailGas flareMorse CodeTalking drumSonar signalsTwitterFacebookLetter writingSign LanguageVideo conferencingInstant MessengerInternetFacial expressionsBird messengerLip readingBrailTalkingFax machine

NetworksA network is a group of two or more computers linked together so that they can share resources (hardware, software and data) and can communicate with one another. A standalone computer is a computer not connected to a network.By joining computers together to form a network, they are able to share a printer. This means that more money can be spent buying a better quality printer and the printer is being used much more of the time.A computer connected to a network is known as a work-stationNetworksIn my own words: a network is the connection of electronic devices enabling them to share hardware, software and data.Types of Computer Network:Local area network (LAN)Wide area network (WAN)The InternetExtranetIntranetVPN (Virtual Private Network)Local area networks (LAN)A LAN consists of a collection of computers that can share peripherals, share information and communicate with each other over a network these computers are likely to be in the same building, area or room.Within a workspace you can have different LANs. Our school consists of a LAN that allows us to access information from the network server. In addition, our computers can also work independently.For a work-station to share information it must have access to a server. A server is a powerful computer that runs the network operating system and allows resources to be shared over the network by other devices. Wide area network (WANs)A WAN can connect to networks across a large geographical area. E.g. a city or country.Information can be transmitted in various ways: using high-speed telephone lines, fiber optic cables, microwave links and satellite links.Mainly used by large companies, universities, and banks with branches in different countries.

Components of a WANModem stands for modulator demodulatorIt is a device used to convert the digital signals emitted by the computer into analogue signals that can be transmitted over a telephone line.Speed at which a modem operates will affect the download time of web pages and files. Data transmission is basically the transmission of data from one location to another for direct use or for further processing.Bandwidth determines the volume of data that can be transmitted in a given time. Usually measured in bits per second. (bps)

Components of a WANThe higher the bandwidth, the quicker the data will flow along the lineWeb pages load quicker.Multimedia is downloaded faster.Internet connection is faster.Less network traffic.Quicker response time.

Components of a WANNarrowband is used to refer to data transmission over a telephone line using an analogue modem that can transmit data at speeds up to 56 Kbps or (56 Kbaud) To access the Internet, narrowband users dial up a remote computer that provides Internet access.Broadband refers to data transmission using ADSL (Asymmetric Digital Subscriber Line) and cable. ADSL is a means of transmitting digital signals using telephone lines and can be many times faster than narrowband. A network of ATMs is a WAN.

The InternetInternet is the largest WAN an international network of networks that connects computer worldwide.WANS can be connected together using the Internet, leased lines or satellite links.It consists of:WWW World Wide Web.Forums where people can seek help and advice about a topic. Research databases used by universities and large companies.USENET discussion groups about a specific subject from the latest boy band to favorite pets for example Google GroupsEmail and Instant Messaging systems.

The InternetNote that no-one owns the Internet.Each of it is made up of individual networks that some has put together and then linked to the Internet.However, each network has to obey Internet standards in order to connect and there are groups set by the US Government that organize things such as web addresses.The Internet is not the same as the WWW.The Internet is to the World Wide Web as Europe is to Germany.

Connecting to the Internet - ISPAn ISP (Internet Service Provider) sells Internet access to companies and individuals.It provides web servers which connect to the Internet.As ISP will provide its customers with a wide range of services:Bandwidth options.Email service.Web hosting. Online and Telephone assistance.Connecting to the Internet - ISPDial up or narrow bandIs when the computer dials a phone number to connect you to your ISP using a telephone line.BroadbandA single cable that can provide cable TV, telephone and Internet services.Available over a telephone line or cable, or mobile telephone network.Connecting to the Internet - HardwareA computerAn internal or external modem or similar deviceSatellites, fiber optic cables or radio waves.Connecting to the Internet SoftwareTCP/IP (Transmission Control Protocol/Internet Protocol)A set of protocols used to transfer data from one computer to another over the Internet.A protocol is a set of rules that defines how computers interact or communicate with each other.Most modern operating systems implement the TCP/IP standard.Connecting to the Internet SoftwareBrowser software allows users to view and use the web pages on the Internet.An Address Bar.A Navigation Bar. A Bookmark/Favorites Option.A Search Engine.A History Button.Browser Setting and Internet Options e.g. Filtering.Connecting to the Internet - othersInternet addressEvery device on the Internet has an unique address that identifies it. This address is a number called the IP address. The IP address could be static (it remains the same every time you connect to the Internet) or dynamic (a temporary address that changes each time you connect to the InternetWeb addresses or URLsWWWThe World Wide Web is a multimedia service that runs on the Internet.The web consists of hypertext and hypermedia documents.This documents contains hyperlinks to other documents located on the same computer or on another computer in any part of the world.All the information that can be accessed via the Internet is often called Cyberspace.Uniform Resource LocatorsUniform Resource Locators is the full form of URL.Example: http://go.microsoft.com/fwlink/?LinkId=69157TypeOfResource://HostComputer.Domain/Directory/SubDirectory/Filename.Extensionhttp://www.cislagos.com/students/exams/timetable.docFile Names and ExtensionsMicrosoft Word: timetable.docMicrosoft Excel: timetable.xlsMicrosoft PowerPoint: timetable.pptxMicrosoft Access: timetable.dbsA Text Editor: timetable.txtA Zipped File: timetable.zipA Webpage: timetable.htmlAn Adobe File: timetable.pdfA Graphics File: timetable.gif

What can you do on the Internet and on the Web?View web pagesUse a search engine to find pages you wantSend and receive e-mailsShop online (e-commerce)Online banking (e-commerce)Bet onlineAccess customer supportSoftware download and distributionAccess and discuss information via mailing lists, bulletin boards and news groupsChat onlineVideo conferencingWeb broadcastingSet up your own website or blog or wikiUse social networking sitesTaskResearch on any two of the following: Online shoppingOnline bankingWeb broadcastingSocial networkingDiscuss the advantages and disadvantages as well as the impact on society.Choose an organization or business as a case study.Online ShoppingOnline shopping is the ability to shop over the internet.AdvantagesConvenience You dont have to wait in lines to pay for your goods. You can easily find information about availability and shop at any time of the day. You can do it at your own time and pace.Better prices Cheaper deals because goods come directly from manufacturers. Many online stores have special offers and discounts.Variety there is typically a wider range of products on online shopping sites. You neednt compromise your choices because of lack of options.Online ShoppingDisadvantagesYou do not physically see the items, and if you are shopping at an online clothing store you are never too sure if the items are your size.You may have to wait a while before the items arrive especially if you are buying something internationally. You also have to pay postage sites. Chances of mishandling. If your goods never arrive then you have no location to go back too.Online security Making payments are not always safe and hackers may get into your bank details.Knowledge of Operating Computer Older people especially may find some websites difficult to use and are not very confident in using a computer therefore will not use online shopping.

Online ShoppingImpact On SocietyThe High Street may shrink as we start to do more of our shopping online. Finding exactly what we want. Finding the cheapest or most competitive pricing.

When it works internet shopping can be great. When it fails it can really mess things up. Delays in dispatching orders; orders that never show up; incorrect orders etc all cause problems. Sometimes it is a dive into the unknown. At present credit card companies are taking the brunt of this. Sooner or later they will change their way of operating to cut their losses.

I also think we may start to buy more. It is far to easy to buy over the internet. Far to easy to shop with instant credit.

http://uk.answers.yahoo.com/question/index?qid=20081004102704AASQ5mf26Online Shopping - AmazonAmazon allows you to purchase materials cheaply without any limit and without any restrictions.It gives you the chance to make a free selection and comparison between prices of goodsYou have the luxury of shopping from anywhere around the world at any timeHowever, there are occasional security infringementsAccordingly, many losses equally occurred to the customer and the merchant due to such acts of hackers who reveal the information and credit cards details. In addition, the Electronic Marketing caused many merchants, agents and monopolists to be vanquished because it gave the chance for direct communications between the producer and the consumer without passing through them; as such, many of such merchants have been yielded away from the way of this new technology. Web BroadcastingWeb broadcasting is being able to stream videos on the internet.AdvantagesEasily watch videos at a click of a buttonYou can easily upload videos and share between friendsAvailable globallyAbility to spread informationDisadvantagesCannot control content on siteSlow internet connection can make using the website very irritating

http://www.surfnetkids.com/go/safety/170/pros-and-cons-of-youtube/http://articles.submityourarticle.com/Steve-Duval-7594/twitter-97888.php28Web Broadcasting - YoutubeIt is public, so anyone can see the videos you postAnyone for the most part can post a videoThere is violence on some of the videos on the siteThere are explicit videosThere is some animal abuse in the videosTeens are recording violence to post on YouTubeThere could be issues of privacy invasionThere could be copyright infringement issuesWeb Broadcasting - YoutubeUsing YouTube to reach the media is cheap and easy.YouTube will show most any videoThe service is clean and clearYouTube has a wide variety of videos, infomercials, how to videos and much moreYou can stay up to date with the new videos at YouTubeExpressing your creativity through YouTube is a major benefitGetting to know people through YouTube is greatLearning through YouTube is greatYou can get a good deal of information to many people in a short amount of timeBecoming a member is easierEase of useNo need for tons of equipment, computer, video equipment, microphone and editing softwareSaves money on marketing