1 / 17

Chapter 9

Chapter 9. Communications and Networks. Competencies (Page 1 of 2). Discuss connectivity, the wireless revolution, and communication systems Describe physical and wireless communications channels Discuss connection devices, including modems, T1, DSL, cable modem, and satellite connections

eleanor-dennis
Download Presentation

Chapter 9

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 9 Communications and Networks

  2. Competencies (Page 1 of 2) • Discuss connectivity, the wireless revolution, and communication systems • Describe physical and wireless communications channels • Discuss connection devices, including modems, T1, DSL, cable modem, and satellite connections • Describe data transmission factors, including bandwidths and protocols • Discuss network and key network terminology Page 238

  3. Competencies (Page 2 of 2) • Describe different types of networks, including local area, metropolitan area, and wide area networks • Describe network architectures, including configurations and strategies • Describe organizational uses of Internet technologies, including intranets, extranets, and firewalls Page 238

  4. Communications The process of sharing data, programs, and information between two or more computers Page 240

  5. Communication Systems • Four basic elements • Sending and receiving devices • Communication channel • Connection devices • Data transmission specifications Page 241

  6. Communication Channels • Channels carry data from one computer to another • Two categories of communication channels • Physical connection • Wireless connection Page 242

  7. Physical Connections • Telephone lines • Coaxial cable • Fiber-optic cable Return Page 242

  8. Wireless Connections -Infrared, Broadcast Radio, Microwave • Infrared • Broadcast radio • Wi-FI (wireless fidelity)/802.11 • Microwave • Stations • Bluetooth • Satellite • GPS Microwave dish Page 242

  9. Connection Device Signals • Types of signals • Analog • Digital Page 244

  10. Connection Device Types • Types of modems • External • Internal • PC Card • Wireless Page 244

  11. Connection Services • Dial-Up services • Leased lines – T1, T2, T3 and T4 • Digital subscriber line (DSL) • Uses existing phone lines • One type widely used is ADSL • Cable modems • Uses existing TV cable • Provides speeds as fast as DSL at a lower cost • Satellite/air connection services • Seven times faster than dial-up • Slower than DSL & cable modem Page 245

  12. Typical User Connection Costs & Speeds Page 245

  13. Bandwidth • Measurement of the capacity of the channel • Categories • Lowbandwidths or Voiceband • Medium band • Broadband • Used for high capacity transmission • Used by DSL, cable, and satellite Page 246

  14. Protocols • Set of communication rules • Standard for Internet: TCP/IP (Transmission control protocol/Internet protocol) • Identifies devices • Reformats information Page 247

  15. Networks • A computer network is a communication system • Connects two or more computers • Allows information exchange Page 247

  16. Network Types • A local area network (LAN): computers are physically close to each other, usually in the same building • Metropolitan area network (MAN) links two or more LANs within a city • A wide area network (WAN) extends over a long distance • Each network site is a node on the network • Data transmitted over common pathways called a backbone Page 249

  17. Internets and Extranets • Intranets • Private network within an organization • Provides information to employees • Extranets • Private network that connects organizations • Used to allow suppliers and others access • Firewalls • Security system • Protects against external threats Page 257

More Related