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Chapter 9 Communications and Networks Chapter 9 Objectives Discuss the components required for successful communications Identify various sending and receiving devices Explain the purpose of communications software Describe various types of lines for communications over the telephone network Describe uses of computer communications Describe commonly used communications devices List advantages of using a network Discuss different ways to set up a home network Differentiate among client/server, peer-to-peer, and P2P networks Identify various physical and wireless transmission media Describe the various network communications standards Next Communications What are computer communications?  Process in which two or more computers or devices transfer data, instructions, and information p. 460 Fig. 9-1 Next Communications What is needed for successful communications? Sending device — initiates instruction to transmit data, instructions, or information Communications device — connects the sending device to the communications channel Communications device — connects the communications channel to the receiving device p. 460 - 461 Communications channel — media on which data, instructions, or information travel Receiving device — accepts transmission of data, instructions, or information Next Uses of Computer Communications What are some uses of communications technology? Internet Chat Rooms FTP p. 462 Web Instant Messaging E-Mail Newsgroups Web Folders Internet Telephony Video Conferencing Fax Machine or Computer Fax/Modem Next Uses of Computer Communications What are wireless messaging services? Text messaging Wireless instant allows users to send messaging allows and receive short wireless mobile text messages on a devices to exchange smart phone or messages Picture messaging PDA allows users to send graphics, pictures, video clips, sound files, and short text messages p. 463 - 464 Next Uses of Computer Communications What are public Internet access points and cybercafés?   Public Internet access point allows wireless connection to Internet in public location Cybercafé is coffee house that provides computers with Internet access Click to view Web Link, click Chapter 9, Click Web Link from left navigation, then click Hot Spots below Chapter 9 p. 464 Fig. 9-5 Next Uses of Computer Communications What is a global positioning system (GPS)? Step 1. GPS satellites orbit Earth. Every thousandth of a second, each satellite sends a signal that indicates its current position to the GPS server. Step 2. A GPS receiver (such as in a car, a PDA, a watch, a handheld device, or a collar) determines its location on Earth by analyzing at least 3 separate satellite signals from the 24 satellites in orbit. Click to view Web Link, click Chapter 9, Click Web Link from left navigation, then click GPS below Chapter 9 p. 466 Fig. 9-6 Next Uses of Computer Communications What are collaboration and groupware?  Collaboration is working with other users connected to a server   Microsoft’s NetMeeting allows collaboration Groupware is software that allows people to share information p. 467 - 468 Fig. 9-7 Next Uses of Computer Communications What are voice mail and web services?   Voice mail is voice message converted to digital form Web services describe standardized software that enables programmers to create applications that communicate with other remote computers over the Internet p. 468 Fig. 9-8 Next