Presentation on theme: "“TELECOMMUNICATIONS AND THE INTERNET”"— Presentation transcript:
1“TELECOMMUNICATIONS AND THE INTERNET” BYSUMANA SHARMA
2TELECOMMUNICATION IN ORGANIZATIONS! The whole world is within your reach!
3SIMPLIFYING THE JARGON! Telecommunications refers to the transmission of information (voice,data,pictures,video,sound) from one point to another over a network.Bandwidth is the data carrying capacity of the network. Greater the bandwidth,faster is the speed of data transmission!
4INTERPERSONAL COMMUNICATION APPLICATIONS e Mail or Electronic mailInternet relay chat or instant messagingNewsgroupsMailing listsFaxVoice mailVideo conferencing
5BUSINESS COMMUNICATION APPLICATIONS e Commerce or Electronic commerceElectronic data interchange(EDI)TelecommutingElectronic funds transferDistance learningTelemedicine
6COMPONENTS OF A COMPUTER NETWORK Sender or a TransmitterReceiverTransmission mediaProtocols or rules
7TYPES OF COMMUNICATION REAL TIMEInstant messaging, video conferencingNON REAL TIMEE mail, voice mail.
8HOW DO COMPUTERS COMMUNICATE WITH EACH OTHER? Computers talk in Binary Language.They use different combinations of the digits 0 and 1 to express all that they want to say!If we wish to communicate with a computer we would need to translate!The process of translation is called “digitization”
9COMPUTING – HOW COMPUTERS PERFORM TASKS? Centralized computingDistributed computingCollaborative computing
10TYPES OF COMPUTER NETWORKS PRIVATE BRANCH EXCHANGE OR PBXWhile at work, majority of the telephone calls made by employees are for intra-company communication!It is feasible for medium to large businesses to have their own telephone exchange.
11LOCAL AREA NETWORKA group of computers and other devices in a relatively limited area (such as a single building) that are connected by a communications linkenables every device to interact with any other device on the network
12CAMPUS AREA NETWORKAn interconnection of local-area networks within a limited geographical space, such as a school campus or a military base.
13WIDE AREA NETWORK (WAN) A system of interconnected computers encompassing a large geographic range, including cities, states, or countries
14METROPOLITAN AREA NETWORK A data communications network thatcovers an area larger than a campus area network and smaller than a wide area network,interconnects two or more LANs, andusually covers an entire metropolitan area, such as a large city and its suburbs.
15PERSONAL AREA NETWORKNetwork in which all devices are distributed locally around an individual person (range is from m).These different devices are capable of communicating with each other!
16GLOBAL AREA NETWORKAn international network that spans all departments, offices, and subsidiaries of the corporation.
17ENTERPRISE NETWORKA term coined by IBM to describe a private network, linking sites within a company.
18VALUE ADDED NETWORKThis is is a privately owned, or proprietary network.A company that acts as a clearinghouse for electronic transactions between trading partners
19INTERNET INTERNET IS NOTHING BUT A NETWORK OF NETWORKS!! Born when DoD started a project called Advanced Research Projects Agency Network (ARPANET)Goal was to develop a decentralized system that could withstand an enemy attack.UCLA, SRI, UCSB, and Utah were the first four nodes.
20INTERNET RELIES ON PACKET SWITCHING TECHNOLOGIES A huge amount of data can be split into smaller chunks and then sent across the transmission medium.At the receiving end all the chunks are put together to retrieve the original data.Very efficient technology that makes best use of available bandwidth!
21HOW DO NETWORKS TALK TO EACH OTHER? Using TCP/IP (Transmission control protocol/Internet protocol).TCP deals with breaking a large piece of data into manageable chunks. These tiny packets of data are called datagrams.IP deals with attaching an address label over them so that that they can reach the desired destination.
22ROUTERS- A MEANS OF CONNECTING TWO NETWORKS High speed device capable of relaying data from one network to another.
23DIFFERENCE BETWEEN INTERNET AND THE WORLD WIDE WEB OR WWW Internet is a network of networks while the world wide web is a collection of documents(web pages) that are held on and sent through the internet
24IP ADDRESSES AND DOMAIN NAMES The internet is a massive computer network comprising of millions of computers.Each computer has a unique address associated with it.This is called an IP address. For example: is an IP address.This Numeric address can be mapped to a name (web address) for ease of remembering.
25DOMAIN NAME OR URL (UNIFORM RESOURCE LOCATOR) Domain name is an alias for the “difficult to remember” IP address.Example :WebEducational institutionsDomain name
26ROLE OF ICANN IN MANAGING IP TO DOMAIN NAME MAPPING ICANN (Internet corporation for assigned names and numbers) manages the exhaustive database consisting of domain names and their corresponding IP addresses and vice versa.
27WORLD WIDE WEBA web browser provides an easy-to-use interface for accessing the information on the World Wide Web.Hypertext documents contains information and hyperlinks.Hyperlinks are links to other related documents.Web pages are written in HTML (Hyper text mark up language)
28INTERNET IS NOBODY’S PRIVATE PROPERTY! Nobody owns the internet!Many non-profit organizations help in maintaining it though!Examples:ISOC (Internet society)ICANN (Internet society for assigned names and numbers)IAB (Internet architecture board)
29DIFFERENT WAYS OF ACCESSING THE INTERNET Individuals usually connect to the Internet using either:Dial UpDSL or Digital subscriber lineISDN or Integrated services digital networkCable modemsSatellite connections
30DIAL UP Uses normal telephone line to establish a connection. Maximum speed of 56 Kbps can be achieved.
31DIGITAL SUBSCRIBER LINE Uses normal telephone line to achieve extremely high data rates.Two popular variations are :ADSL or Asymmetric DSLDownstream speed of 1.5 Mbps to 9 MbpsUpstream speed of 16 to 640 KbpsSDSL or Symmetric DSLDownstream and upstream speeds of 3 Mbps
32CABLE MODEMS Utilizes coaxial cable to access the internet. Requires a cable modem to be installed.Data rates of upto 2 Mbps can be achieved.
33SATELLITE CONNECTIONS Utilizes geostationary satellites to access the internet.Propagation delay is a major concern
34HOW BUSINESSES OR OTHER ORGANIZATIONS ACCESS THE INTERNET Using Leased lines.Using ATM or Asynchronous transfer mode networks
35LEASED LINEA leased line is a dedicated phone line to your telephone exchange.It has two popular variants:T1 = 24 telephone linesData rates of upto 1.5 MbpsT3= 672 telephone linesData rates of upto 45 Mbps
36ATM Based on packet switching. Fixed packet size of 53 bytes. Data rates of upto 2.2 Gbps can be achieved.
37SECURITY – THE MILLION DOLLAR QUESTION! AuthenticationLog in with your passwordFirewallsShield information from hackers or unauthorized users!EncryptionThe sender turns on the lock.Only the receiver has the key
38POPULAR INTERNET TOOLS e mail: Used for transmitting and receiving messages.Telnet: An Internet protocol that allows a user at a remote terminal to login to other computer systems on the InternetFTP or File transfer protocol:A way of transferring files over the Internet from one computer to another.
39Internet tools - continued Usenet: Collection of newsgroups across the internet.Mailing lists: Allows group of people with a common interest to send messages to each other.Archie: Juggle through FTP sites to see if they have the information you are looking for!
40Internet tools - continued Gopher: Was the means of accessing information(plain text) on the internet, before the world wide web was born!VoIP or Voice over IP: A technology for transmitting ordinary telephone calls over the Internet using packet-linked routesWAIS or Wide area Information server: distributed information retrieval system on the Internet used to retrieve documents using keywords searching defined databases.