ITP 140 Mobile Applications Technologies. Internet

Transcription

1 ITP 140 Mobile Applications Technologies Internet

2 What is the Internet? History of the Internet World Wide Web Internet Addresses Electronic Communication Overview 2

3 What is the Internet? Global interconnected series of smaller networks Networked networks or network of networks Communication infrastructure for exchanging information Networks communicate based on certain protocols Transmission Control Protocol / Internet Protocol (TCP / IP) Who runs it? US Government NO! No single person, group, or organization 3

4 Quote On-line interactive communities... will be communities not of common location, but of common interest... the total number of users...will be large enough to support extensive general purpose [computers]. All of these will be interconnected by telecommunications channels... [to] constitute a labile network of networks--ever changing in both content and configuration. J. C. R. Licklider 4

5 History 1950s & 1960s 1957 USSR launches Sputnik First artificial satellite to be put into Earth's orbit 1958 US forms ARPA Advanced Research Projects Agency 1960 J.C.R. Licklider publishes his landmark paper Man-Computer Symbiosis 1961 Leonard Kleinrock, MIT, writes paper on packet-switching theory Information Flow in Large Communication Nets 1962 Licklider becomes the first head of the computer research program at ARPA 1966 Larry Roberts, MIT, writes the first ARPANET plan "Towards a Cooperative Network of Time-Shared Computers" 5

6 History ARPANET commissioned by the Department of Defense for networking research First node installed by BBN at UCLA & then 4 host computers (UCLA, Stanford Research Institute, UCSB, University of Utah) 6

7 History Oct 29, First communication attempt! Professor Leonard Kleinrock guided the UCLA team that sent the first "host-to-host" message His student assistant Charley Kline attempted to logon to host at SRI Tried to send the message "log", but the system crashed before the "g arrived The second attempt at logging on worked 7

8 History 1970s nodes established, including UCLA, SRI, UCSB, University of Utah, MIT, RAND, Harvard, Lincoln Lab, Stanford, CMU, NASA/Ames, and BBN program by Larry Roberts, MIT, and Ray Tomlinson, BBN (Bolt, Beranek and Newman) First was something like "QWERTYUIOP" 1971 ARPA renamed to DARPA (Defense) 1973 first overseas connection at University College of London 1973 Bob Metcalfe designs Ethernet for his Harvard PhD Thesis 1974 The Fathers of the Internet Vint Cerf and Bob Kahn publish a paper titled A Protocol for Packet Network Interconnection TCP Transmission Control Protocol 1976 Queen Elizabeth sends an ! 1979 emoticons were born :-) 8

9 ARPANET Map

10 ARPANET Map

11 History 1980s 1980 ARPANET is completely shut down due to an accidentally propagated virus 1982 DCA and ARPA establish TCP/IP as the protocol suite for ARPANET Transmission Control Protocol (TCP) and Internet Protocol (IP) DoD declares TCP/IP as standards for DoD networks First definitions of internet as a connected set of networks using TCP/IP Defines Internet as a networks of internets 1983 ARPANET split into ARPANET and MILNET 1984 Domain Name System (DNS) was invented by Paul Mockapetris of USC/ISI to resolve host names into IP addresses Number of hosts exceeds 1,000 11

12 History 1980s continued 1985 Information Sciences Institute (ISI) at USC is given responsibility for DNS root management Jon Postel First registered domain symbolics.com Others registered that year ucla.edu, rice.edu, berkeley.edu, mit.edu, css.gov 1986 NSFNET backbone is created with a speed of 56Kbps & NSF establishes 5 super-computing centers to provide high-computing power for all JVNC@Princeton, PSC@Pittsburgh, SDSC@UCSD, NCSA@UIUC, Theory Center@Cornell 1988 Robert Morris Jr. releases a worm affecting ~6,000 of the 60,000 hosts on the Internet The Computer Emergency Response Team (CERT) is created by DARPA 1989 more than 100,000 hosts connected to NSFNET NSFNET became a major part of what is known as the Internet backbone 12

13 History Early 1990s 1990 ARPANET disconnected 1990 World Wide Web (WWW) is developed by Tim Berners-Lee at Swiss-based CERN (European Organization for Nuclear Research), thus the first web page ( NSFNET backbone upgraded to T3 (44.736Mbps) & NSFNET traffic passes 1 trillion bytes/month and 10 billion packets/month 1992 Internet Society is chartered, # of hosts breaks 1,000,000 & the term Surfing the Internet is coined by Jean Armour Polly 1993 InterNIC created by NSF to provide services: Directory & database service by AT&T Registration services by Network Solutions Inc Information services by General Atomics/CERFnet 1993 Mosaic was the first popular WWW browser Developed by the National Center for Supercomputing Applications (NCSA) US White House comes on-line ( 13

14 History 1990s & 2000s 1995 NSF establishes the very high speed Backbone Network Service (vbns) linking super-computer centers NSFNET reverts back to research network Internet solely exists as a network between ISPs, universities and their connections 1995 Sun Microsystems launches JAVA and RealAudio, an audio streaming technology, is created 2000 The high-speed Internet2 backbone deploys IPv6, the next generation of IP standards A distributed denial of service (DDoS) attack struck the 13 DNS root servers knocking out 8 of them 2003 The SQL Slammer worm causes DDoS attack taking roughly 10 minutes to spread worldwide Took down 5 of the 13 DNS root servers along with tens of thousands of other servers, and impacted a multitude of systems ranging from (bank) ATM systems to air traffic control to emergency (911) systems 2004 VeriSign Naming and Directory Service (VNDS) begins updating all 13.com/.net authoritative name servers in near real-time vs. twice each day 14

15 History Resources Internet Society Brief History of the Internet Hobbe s Internet Timeline v8.2 Nerds Timeline ARPANET Map 15

16 History Graphs 16

17 History Started as a research project funded by Advanced Research Projects Agency (ARPA) Created ARPANET WWW is the killer app of the Internet ARPA (1962) à DARPA (1971) à ARPA (1993) à DARPA (1996) Defense Advanced Research Projects Agency 17

18 Important Internet People Licklider first head of the computer research program at ARPA Kleinrock packet-switching theory Roberts ARPANET plan Roberts & Tomlinson program Cerf & Kahn protocols for Internet à TCP/IP Mockapetris invented Domain Name System Postel DNS management Berners-Lee WWW 18

19 What about Al Gore? "During my service in the United States Congress, I took the initiative in creating the Internet. Al Gore in an interview with Wolf Blitzer, 1999 "Al Gore was the first political leader to recognize the importance of the Internet and to promote and support its development. Vinton Cerf, called the Father of the Internet, September 2000 Congressman Gore promoted the idea of high speed telecommunications as an engine for both economic growth and the improvement of our educational system. 19

20 What is the World Wide Web? Globally connected network of websites Collection of web pages, websites, and web servers Killer app of the Internet Access through a protocol called Hypertext Transfer Protocol (http) Application used to access the WWW is a web browser Mozilla Firefox browser Google's Chrome Microsoft s Internet Explorer Apple s Safari 20

21 Web Addresses Specific location is known as an address or URL (Uniform Resource Locator) Example: http protocol domain name.edu top level domain name Read address from right to left Top-level domain, major domain, computer running the web server For example, 21

22 Domain Names Domain names were created to provide easy-to-remember monikers for IP addresses e.g. When you type microsoft.com you re really referring to IP Translation between domain names and IP addresses is performed by the Domain Name Service (DNS) Computers called name servers 22

23 Generic Top-Level Domains (gtld) Domains that are three or more letters Before 1998, there were only eight which included.net,.com, and.gov Seven more were made available in 2000 including.biz,.museum, and info In 2004, a further eight domains were added including.xxx The Internet Corporation for Assigned Names and Numbers (ICANN) announced a staggered gtld release over the next three years. 23

24 .com and.net gtlds Operated by VeriSign Global Registry Services.org Noncommercial organizations including nonprofit and nongovernmental organizations, charities, religious organizations, etc. Managed by the Public Interest Registry (PIR) Created by the Internet Society (ISOC) 24

25 gtlds.edu Postsecondary accredited institutions & registered only through Educause (via Verisign).gov US government & operated by US General Services Administration (via Verisign).int Registering organizations & operated by IANA (Internet Assigned Numbers Authority).mil US military & operated by US Department of Defense 25

26 Other (examples) gtlds.adult.aero.app.archi.audio.biz.cat.college.com.coop. .global.gop.green.guru.help.house.info.jobs.land.link.loan.lol.love.menu mobi.museum.name.ngo.photo.post.pro.property.solar.sucks.systems.travel.xxx.xyz 26

27 Country Code Top Level Domains (cctld) All two letter domains Examples.ca Canada.eu European Union.tv Tuvalu.uk United Kingdom Listing (not all).ac.ad.ae.af.ag.ai.al.am.an.ao.aq.ar.as.at.au.aw.ax.az.ba.bb.bd.be.bf.bg.bh.bi.bj.bm.bn.bo.br.bs.bt.bw.by.bz.ca.cc.cd.cf.cg.ch.ci.ck.cl.cm.cn.co.cr.cu.cv.cx.cy.cz.de.dj.dk.dm.do.dz.ec.ee.eg.er.es.et.eu.fi.fj.fk.fm.fo.fr.ga.gd.ge.gf.gg.gh.gi.gl.gm.gn.gp.gq.gr.gs.gt.gu.gw.gy.hk.hm.hn.hr.ht.hu.id.ie.il.im.in.io.iq.ir.is.it.je.jm.jo.jp.ke.kg.kh.ki.km.kn.kr.kw.ky.kz.la.lb.lc.li.lk.lr.ls.lt.lu.lv.ly.ma.mc.md.mg.mh.mk.ml.mm.mn.mo.mp.mq.mr.ms.mt.mu.mv.mw.mx.my.mz.nc.ne.nf.ng.ni.nl.no.np.nr.nu.nz.om.pa.pe.pf.pg.ph.pk.pl.pm.pn.pr.ps.pt.pw.py.qa.re.ro.ru.rw.sa.sb.sc.sd.se.sg.sh.si.sk.sl.sm.sn.sr.st.sv.sy.sz.tc.td.tf.tg.th.tj.tk.tl.tm.tn.to.tr.tt.tv.tw.tz.ua.ug.uk.us.uy.uz.va.vc.ve.vg.vi.vn.vu.wf.ws.ye.yt.yu.za.zm.zw 27

28 How the WWW Works Client/server model Web browser on your machine is the client Server software runs on a web host 28

29 Client/Server Model Your computer wanting to access the Internet is the client Other computers are the servers (or hosts) waiting for requests Servers provide services to the clients such as delivering web pages, handling , etc. For WWW, the client is the web browser on your computer and the server is a host computer located somewhere on the Internet Client s browser sends HTTP (Hypertext Transfer Protocol) requests to a host server Host computer runs the server software that reads the request and performs the asked-for services (for example, web server software enables the host to locate requested page & return it) 29

30 How the WWW Works Type a URL in your web browser Web browser sends a request using Hypertext Transfer Protocol (HTTP) Defines the way the web browser & web server communication with each other URL (e.g., First part ( details the protocol to use Second part (www) indicates which type of resource Third part (cnn.com) identifies the web server Final part (/TECH/) identifies a specific directory or page The request is sent to the Internet with routers figuring out the web server The web server receives the request using the HTTP protocol The server finds the requested page and sends it back to the web browser client HTTP connection is closed 30

31 Accessing the Internet Internet Service Providers (ISPs) Services connected to the Internet You connect to the ISP network and the ISP is connected to any network you want to reach Examples: AOL, TWC, AT&T, Verizon, SpeakEasy, etc. 31

32 Web Browser Displays information sent from the server so it can be seen and read by the user Also allows the user to send data back to the server Browsers can t display some types of files such as Flash Use a helper application or plug-in which you install Windows cursor turns into a spinning hourglass when your browser is trying to connect to a website 32

33 Graphical User Interface (GUI) What the user sees and interacts with Type of user interface that allows users to interact with electronic devices with images rather than text commands Components Icons Pointer Window Menus Dialog Boxes Toolbars 33

34 Early GUI Modern day GUI first conceived at Stanford Research Institute (SRI) Douglas Englebart Published a paper called Augmenting Human Intellect in 1962 Envisioned computers as a tool for enhancing human intellect, not replacing it Hypothetical example: using a computer to aid in creating architectural blueprints Modern Day CAD software! Built a mainframe interface with a GUI Utilized a keyboard, pseudo-keypad, and a mouse Yes, he invented the mouse too! 34

35 Earliest GUI 35

36 GUI Development Xerox Palo Alto Research Center (PARC) The PARC user interface Consisted of graphical elements such as windows, menus, radio buttons, check boxes and icons Employs a pointing device in addition to a keyboard WIMP stands for windows, icons, menus and pointing device Xerox Alto released in 1973 An early personal computer The first computer to use the desktop metaphor and mouse-driven graphical user interface (GUI) Xerox 8010 Star Information System released in 1981 The first GUI-centric computer operating model 36

37 GUI Development Apple Apple Lisa released in 1983 $10,000 price tag! Many innovations for GUIs Pull-down menu bar Different icons for files and applications Checkmarks for selected files Double-clicking Cheaper version needed Macintosh 128K released in 1984 $2,

38 GUIs Today 38

39 Killer App Short for killer application Any computer program that is so necessary or desirable that it proves the core value of some larger technology, such as computer hardware, gaming console, software, or an operating system Can substantially increase sales of the platform on which it runs VisiCalc (spreadsheet software) is the earliest generally agreed example of a killer app 39

40 Killer App for Mobile Devices iphone 3 & Android iphone 4s iphone 4 40