Telecommunications

1. Telecommunications

2. Telecommunications Communicating and transmitting information electronically - - - - - - - - (includes transmitting data, text, pictures, voice and video over long distance)

3. How Do We Tele-Communicate? • Phone • Voice mail • Cell phone—also includes texting • Fax—a document generated by using a facsimile machine • Email—transmission of messages and files using a computer network • Instant messaging

4. Methods of Telecommunication • Social networking sites—websites that provide a virtual community in which people with a shared interest may communicate • Telecommuting—the action of working from home using a computer and telecommunications media • Intranet—a company’s private computer network • e-commerce/e-business—buying/selling merchandise or conducting business on the Internet

5. Methods of Telecommunication • Audio conferencing—Communication between three or more sites that are linked by a voice-only telecommunications medium • Video conferencing—Communicate in real time via video with two or more people at different locations

6. Telecommunications & Networks At the heart of telecommunications is the ability to “network” computers together . . . And at the heart of networks is the media through which communication flows: wires, telephone lines, or wireless signals.

7. Networks • A group of two or more computers linked together • Benefits • Instant communication • Information sharing • Hardware sharing • Software sharing

8. Network Components • Server—the computer at the center of a network that manages network resources; more powerful than a desktop computer • Client—any computer on a network that relies on a server for resources, i.e. email, etc. computers that are connected and ready to receive and/or transmit data are said to be online,as opposed to a stand-alone computer: a computer that is not connected to a network

9. Classification by Coverage • Local Area Network—a network that spans a relatively small area; typically is confined to a single building or several buildings • WAN—a network that geographically spans a large area; typically includes 2 or more LANs • There are several variations of WANs • A popular WAN used by large businesses is the VPN

11. Virtual Private Network • VPN—a private network that uses a public network (usually the Internet) to connect remote sites or users together. • Instead of using a dedicated, real-world connection such as leased line, a VPN uses "virtual" connections routed through the Internet from the company's private network to the remote site or employee.

13. What media is used to connect computers to a network or to the Internet? • Two categories of media • Wired Media • Wireless Media A computer will need a network interface card (NIC) to connect to a network or the Internet.

14. Wired Media • Twisted pair cable—cable that consists of two independently insulated wires twisted around one another. Twisted pair is the least expensive type of wire • Coaxial cable—a type of wire that consists of a center wire surrounded by insulation and then a grounded shield of braided wire • Fiber optic cable—a technology that uses glass (or plastic) threads (fibers) to transmit data. Fiber optics provide the best quality but is expensive to install and the cable is more fragile and difficult to splice

18. Wireless Media • Microwave • Satellite • Infrared (remote controls) • Cellular • Wi-Fi (radio waves) • Bluetooth (short-range radio waves)

19. How is informationtransmitted to and from your computer on a network or the Internet? • Modems—phone, cable, DSL • Satellites—provides high speed access for rural, remote areas or mobile vehicles and boats; transmits electromagnetic signals • T Lines—a digital high-speed long-distance telephone line that is capable of carrying multiple types of signals across the line; T-1 / T-4 lines are currently available; typically large companies and organizations qualify