Part 2

 Transmission methods used  Bandwidth:  The speed at which Data can be carried.

 Narrow Band  Technology provides bandwidth that is less than 64 Kb or less. Can be found in telephones lines as well.

 Voiceband  Technology capable of transmitting spoken comunication.

 Broadband  Technology provides bandwidth that is greater than 64Kb per secs or more.

 Broadcasts  Point – to – point

 Radio and television stations use this method to send information to as many of their users as possible.

 This is a direct communication channel between two computers on a network.  Example: When one person calls another a wireless path is created between those two persons. So this ensures that other people in the same vicinity can not receive the call other than who the call is really meant for.

 Data travels over a medium in three ways:  Simplex  Half-Duplex  Duplex

 Simplex Transmission is uni-directional

 Data transmission is bi-directional, but only in one direction at a time.

 Data transmission is bi-directional and permits transmission in both directions at the same time.

 Internet  Intranet  Extranet

 Internet is a public, global network based on TCP/IP protocol.  TCP/IP protocol assigns every connected computer a unique address, also called an IP address.  So any two computers can locate each other.

 This is a private computer network designed to meet the needs of a single organization or company.  It is not necessarily open to the external internet and definitely not opened to users.  It uses similar facilities such as a browser and web pages.

 This is an intranet that has been selectively opened to strategic allies, or associates or even customers.  An online banking application is a good example of this.

 Data communications all over this world is based on the TCP/IP protocol.  Communications with the world wide web is based on a different protocol  HTTP  Others include: FTP, VoIP, Wi-Fi and Bluetooth.

 Hyper Text Transfer Protocol  This is a protocol used to request and transmit files, especially web pages and web page components over the internet or computer networks

 File Transfer Protocol  This is a protocol used to transfer files between FTP servers and clients.

 Voice over IP  This is the use of Internet-based technologies to transmit voice-grade data over the internet.  Great example can be seen with the use of SKYPE, Voice notes in Whats App

 This is a wireless protocol for exchanging data over short distances from fixed and mobile devices, using radio waves.  Bluetooth capabilities are enabled in a device via a Bluetooth chip.

 This is a marketing term and is found in several protocol governing the wireless LAN communications.

 There is a large collection of documents or data called web pages.  Web pages are grouped together to form Web Sites, and stored on Web Servers, downloaded and displayed on users’ computer by a web browser.

 A web page is a document written in Hyper Text Markup Language (HTML), that may contain text, sound, images, video clips, hyperlinks and other components.

 A web site is a group of web pages that belong together and are linked to each other using hyperlinks.  Organizations want viewers to be able to find documents on their web site easily.

 A hyperlink is an icon, information object, underlined or otherwise emphasized word or phrase that displays another document when clicked with the mouse.

 A web server is a special-purpose application software that accepts requests for information, framed according to the Hyper Text Transport Protocol (HTTP).  It processes these requests and sends the requested document.

 A web Browser is a special-purpose application software that runs on an Internet connected computer and uses the HTTP to connect with web servers.

 Uniformed Resource Locator.  This is a string of charactters that uniquely identifies an internet resourec’s type and location. Concider the following:

 guitar.com/c/christina_perri/a_thousand_years_ ver2_crd.htm  Identifies a World Wide Web Document  – Indicates the Internet domain name of the computer on which the document is stored.  /c/christina_perri/a_thousand_years_ver2_crd.h tm – fully describes the directory structure and includes the document’s name.

 Several factors contribute to communication globally.   IRC  BULLETIN BOARDS  BLOGGIN  PODCASTS

 Electronic mail, applications allow users to send an electronic document over a network to anyone with an address.  An address is always in the form for example  Text based, send images power points, videos

 Internet Relay Chat  Is a messaging system that allows users to ‘chat’ with text other people over the internet using text messages.  Windows Live Messenger, Face Book Chat, Google Chat, Yahoo Chat, e.t.c.

 This is an electronic forum that hosts posted messages and articles related to common subjects.  A newsgroup is an on-line discussion group or forum specifically focused on a particular area of interest.

 A blog or a web log is a diary maintained by its author on the World Wide Web. It allows people to comment on the posts.

 A podcast is an audio broadcasts using the Internet that can be played back on an Ipod or similar device.

 Which of the cable types mentioned do you believe:  (a) has the greatest Bandwidth  (b) is the most costly to purchase and install  (c) is the most common in Local area network

 Suggest one reason why a residential householder would want to purchase a 8MB broadband Internet Service.  Suggest THREE ways in which an extranet may typically be used by an organisation  What is Top-Level-Domain  Give three examples of Top-Level-Domain.