Tom Rebold, MPC FLUENCY WITH INFORMATION TECNOLOGY Skills, Concepts, and Capabilities

Tom Rebold, MPC Becoming Skilled At Information Technology PART 1

Tom Rebold, MPC MAKING THE CONNECTION The Basics of Networking chapter 3  How networking has changed society  Types of communication technology  Internet addresses and DNS servers  Internet protocols  LANs vs ISPs  Internet vs WWW  File heirarchy

4 Social impact of the internet Nowhere is remote –Alaska and New York: equal access to info People are more interconnected –Instant messaging or Social relationships are changing –Decline in social interactions English is becoming a universal language More freedom of speech & assembly –Chat rooms, newsgroups, websites

5 Types of communication Synchronous—both ends active at the same time (telephones) Asynchronous—postcards, answering machine, Broadcast—radio, TV Multicast—magazines Point-to-point—telephone The internet supports all these types (in modified forms)

6 Internet possibilities Synchronous—instant messaging, IP phone Asynchronous— Broadcast—web site Multicast—group , newsgroup Point-to-point—

Copyright © 2003 Pearson Education, Inc. Slide 1-7 A diagram of the Internet The network is a medium just like TV or radio Routers

Copyright © 2003 Pearson Education, Inc. Slide 1-8 Computers connected to the Internet are given IP addresses IP=Internet Protocol Domain names are easier to remember

Copyright © 2003 Pearson Education, Inc. Slide 1-9 A domain hierarchy A domain is a related group of networked computers This diagram locates: spiff.cs.washington.edu tracer.cs.washington.edu And what else?

Copyright © 2003 Pearson Education, Inc. Slide 1-10 Another View of Domains Top level domains (all in US) Also many other countries:.uk.ca.de...

Copyright © 2003 Pearson Education, Inc. Slide 1-11 Hosts like Spiff make requests to a local DNS server...(for DNS: domain name system Server: a computer that serves information DNS servers look up the IP address of domain name ( ) Sometimes more than one DNS server is queried Request goes to the right IP address

Copyright © 2003 Pearson Education, Inc. Slide 1-12 The TCP/IP postcard analogy. (Transmission Control Protocol/Internet Protocol) Messages are broken into small units and sent one at a time to their destination Like sending a novel to your publisher one postcard at a time!

Copyright © 2003 Pearson Education, Inc. Slide 1-13 The Internet makes use of whatever routes are available to deliver packets. Packets go in many directions They may even arrive out of order

Copyright © 2003 Pearson Education, Inc. Slide 1-14 A ping from the author’s machine to eth.ch (Switzerland) makes 19 hops The Internet is a “wide area network” (WAN)

Copyright © 2003 Pearson Education, Inc. Slide 1-15 Robert Metalfe’s original drawing of the Ethernet design; the unlabeled boxes, computers, “tap” onto the wire that Metcalfe has labeled “The Ether.” Computers in our laboratory are on a “local area network” (LAN) using Ethernet Computers listen before talking like people at a party

16 Connecting to the internet You can use an Internet Service Provider (ISP) reached by modem, DSL or cable- modem Or use a LAN in a larger organization (intranet) with access to the internet

17 Internet vs the World Wide Web (WWW) Web server: –a computer (on the internet) that sends web pages to other computers –Web servers and web pages together make up the world wide web (WWW) To request a web page, you provide the URL –(Uniform Resource Locator) like –Page is sent using hypertext transfer protocol ( ( optional )

18 Dissecting a URL d.html Server name Path name to web page— Tells which folders its in And the file name The actual page file name David.html folder

Copyright © 2003 Pearson Education, Inc. Slide 1-19 A Web page

Copyright © 2003 Pearson Education, Inc. Slide 1-20 The HTML source that produced the previous web page. Notice that an additional image file, alto.jpg, is also required to display the page. HTML 1. Takes less space 2. Lets browser adjust image

Copyright © 2003 Pearson Education, Inc. Slide 1-21 A hierarchy diagram showing the path between xerox-alto.jpg and the desktop. Down=deeper into tree, toward the leaves Up=higher, toward the root Directory hierarchy

Copyright © 2003 Pearson Education, Inc. Slide 1-22 Locating the web page on the server gal100

23 Chap 3 review questions 2. English is becoming the universal language as a result of all of the following except: A.American pop culture B.the dominance of science and technology in English-speaking countries C.information technology’s predominant use of English D.the Alto Project 3.Overall, the ability of individuals to create and publish Web pages: A.presents an enormous security risk B.extends human expression C.has led to a proliferation of hate pages and pornographic sites D.has unduly diverted huge sums from other IT projects

24 Chap 3 review questions 5.If the Internet consisted of four computers, there would be six possible connections. If it consisted of five computers, there would be ten possible connections. How many connections are possible with ten computers? A.10 B.30 C.45 D.Infinite 1.eCommerce is the shortened term for _____. 3.A communication that goes out to many people within a specific target audience is called a ______.