1. COMMUNICATION AND NETWORKS 99 computing ESSENTIALS 2 0 0 8

2. Dept.Of Computer Science,XYNC2 Competencies Connectivity Wireless Revolution Communication systems Connection devices Transmissions and protocols Network architecture computing ESSENTIALS 2 0 0 8

3. Dept.Of Computer Science,XYNC3 Connectivity Computer networks that link people and resources Other computers Large storage devices Internet computing ESSENTIALS 2 0 0 8

4. Dept.Of Computer Science,XYNC4 Wireless Revolution Wireless and mobile telephones Most dramatic change in connectivity Connected all the time anywhere Originally voice communication Computer communications Bluetooth Device connections computing ESSENTIALS 2 0 0 8

5. Dept.Of Computer Science,XYNC5 Communication Systems Electronic systems that transmit and receive information Basic elements Sending/Receiving device Communication channel Connection devices Data transmission specifications computing ESSENTIALS 2 0 0 8

6. Dept.Of Computer Science,XYNC6 Communication Channels Essential element of communication system Two categories Physical connection Wireless connection computing ESSENTIALS 2 0 0 8

7. Dept.Of Computer Science,XYNC7 Wired Connections Telephone lines Twisted pair Old standard Coaxial cable – Single solid-copper core – 80 times faster Fiber-optic cable – Light through glass – 26,000 times faster computing ESSENTIALS 2 0 0 8

8. Dept.Of Computer Science,XYNC8 Wireless Connections Microwave High-frequency radio waves Line-of-sight communication Relayed Satellite Microwave relay stations Geostationary Large volume of data computing ESSENTIALS 2 0 0 8

9. Dept.Of Computer Science,XYNC9 Connection Devices Modulator-demodulator Converts analog signal to digital signal Speed in bits per second (bps) External Internal PC Card Wireless computing ESSENTIALS 2 0 0 8

10. Dept.Of Computer Science,XYNC10 Connection Types Dial-up service Most popular, but slow T1 – T4 lines Special high-speed lines Digital subscriber line (DSL) Uses existing phone lines, fast Cable Existing television cables Satellite/air connection services Slower than DSL, but faster than dial-up computing ESSENTIALS 2 0 0 8

11. Dept.Of Computer Science,XYNC11 Data Transmission Bandwidth How much information can be transmitted at one time Protocol Specific rules guiding the exchange of information computing ESSENTIALS 2 0 0 8

12. Dept.Of Computer Science,XYNC12 Bandwidth Measurement of capacity of the communication channel Categories Voice band Standard phone line, dial-up Medium band Special leased lines Broadband High capacity transmissions DSL, cable, satellite computing ESSENTIALS 2 0 0 8

13. Dept.Of Computer Science,XYNC13 Data Transmission Direction Simplex One direction only Half-duplex One direction at a time Full-duplex Both direction simultaneously computing ESSENTIALS 2 0 0 8

14. Dept.Of Computer Science,XYNC14 Protocols Set of communication rules for exchange of information Transmission control protocol/Internet protocol (TCP/IP) Identification IP Address Domain name system (DNS) Reformatting Reassemble packets computing ESSENTIALS 2 0 0 8

15. Dept.Of Computer Science,XYNC15 Networks Two or more connected computers that share information and resources Node Device connected to a network Client Node that requests and uses resources available from other nodes Server Node that shares resources with other nodes computing ESSENTIALS 2 0 0 8

16. Dept.Of Computer Science,XYNC16 More Network Terms Network operating system (NOS) Software to control and coordinate activities between nodes on a network Distributed processing Computing power located and shared at different locations Host computer Large centralized computer, usually a mainframe computing ESSENTIALS 2 0 0 8

17. Dept.Of Computer Science,XYNC17 Network Architecture Arrangement of network communication channel Coordinates and shares resources Topology Star network Bus network Ring network Hierarchical computing ESSENTIALS 2 0 0 8

18. Dept.Of Computer Science,XYNC18 Star Network computing ESSENTIALS 2 0 0 8

19. Dept.Of Computer Science,XYNC19 Bus Network computing ESSENTIALS 2 0 0 8

20. Dept.Of Computer Science,XYNC20 Ring Network computing ESSENTIALS 2 0 0 8

21. Dept.Of Computer Science,XYNC21 Hierarchical Network computing ESSENTIALS 2 0 0 8

22. Dept.Of Computer Science,XYNC22 Strategies Ways to coordinate sharing of resources Most common Terminal network system Peer-to-peer network system Client/Server network system Enterprise computing computing ESSENTIALS 2 0 0 8

23. Dept.Of Computer Science,XYNC23 Network Types Networks differ in geographical size Types of networks Local Area Network (LAN) Metropolitan Area Network (MAN) Wide Area Network (WAN) computing ESSENTIALS 2 0 0 8

24. Dept.Of Computer Science,XYNC24 Local Area Networks Computers and devices linked in close proximity to each other Typically use a bus form of organization Network gateways Network bridge computing ESSENTIALS 2 0 0 8

25. Dept.Of Computer Science,XYNC25 Metropolitan Area Networks Link nodes and resources within the geographical bounds of a city Link between buildings Cellular phones can extend the reach of a MAN computing ESSENTIALS 2 0 0 8

26. Dept.Of Computer Science,XYNC26 Wide Area Networks Countrywide and worldwide network Use microwave relays and satellites Internet Widest of all WAN computing ESSENTIALS 2 0 0 8

27. Dept.Of Computer Science,XYNC27 Look to Future Wireless robotic car Toyota and Sony collaboration Pod Connects wirelessly to portable terminal Download songs from Internet Use GPS to determine location Communicate with other cars computing ESSENTIALS 2 0 0 8