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Navigating the Internet for Consumers: ISPs, Connections, Searching, Portals

Explore the basics of the internet including HTML, ISPs, network connections, and web navigation. Learn about different internet connections, search engines, and tips for efficient web browsing.

bradley-crosby
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Navigating the Internet for Consumers: ISPs, Connections, Searching, Portals

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  1. Information Consumers Computer Science 01i Introduction to the Internet Neal Sample 20 February 2001

  2. We will talk about... • HTML odds and ends • Internet Service Providers • Networks Connections • Searching • Portals

  3. Some HTML Tidbits • Changing fonts <font face=“Helvetica, Courier, Arial” size=+2> • Changing colors <font color=RED> <font color=#FFFFFF> • Changing background images <body background=“background.jpg”>

  4. Tables • Basic Tables <table border=“3”> table <tr> row <td bgcolor=“red”>Hi!</td> data (aka “cell”) <td>Bye!</td> </tr> </table> • Wide Cells <td colspan=“2”>This is a double-wide cell</td> • Tall Cells <td rowspan=“2”>This is a double-tall cell</td>

  5. View HTML Source! • In Microsoft Internet Explorer: • right-click on a web page • select “view source” or • select “View” from the toolbar • then “source” • In Netscape, same process

  6. Internet Service Providers (ISPs) • Connect isolated machines to the Internet • On campus, Stanford is your “ISP” • one of the best you’ll ever have =) • Thousands of them out there • Big ones with portals and content, like AOL • Hackers providing dial-up shell accounts out of the spare bedroom (www.lariat.org)

  7. Picking an ISP • What is your user profile? • What is its pricing structure, flat or usage? • What speed modems does it support? • Is it Mac or Unix friendly? • What support options are there? • Does it offer web-hosting? Shell accounts? • What do your friends say?

  8. Consumer Grade Connections • Modem • 56 Kilobits per second/high latency • Free - $20 per month • Cable modem: • 128 Kilobits per second (and up) • $30+ per month, plus hardware and setup • Cellular Modem • 128 Kilobits per second/high latency • $20+ per month, plus hardware • But mobile!

  9. High-End/Small Office Connections • Integrated Services Digital Network (ISDN) • 128 Kilobits per second/low latency • $40 per month plus hardware • Requires new phone line in your home • Share voice and data over the same line • Digital Subscriber Line (DSL) • Up to 7 megabits per second downstream, 680 Kilobits per second upstream/low latency • $40-$250 per month plus hardware • Normal phone lines

  10. Industrial Strength Connections • T1 line • 1536 Kilobits per second/extremely low latency • < $750 per month, plus installation, router and hardware • T3 line • 44.7 megabits per second/extremely low latency • Negotiated pricing, < $10,000+ per month • Stanford has one (+ an “I2 connection”)

  11. The challenge for a Web Consumer: Navigation: “How do I find my way around the web?”

  12. Web Navigation • How can structure be imposed over all the information out on the web? • Bookmarks • Pages of links • Searching • Portals • Rings

  13. Bookmarks • Avantages • Convenient • Structure added by the consumer • Take you directly where you want to go • Always customized properly • Disadvantages • Can only bookmark where you’ve been • Not dynamic • Easily get disorganized themselves • Not accessible from any machine? (www.mybookmarks.com)

  14. Links Pages • Advantages • More easily organized than bookmarks • Someone else usually does them • Available anywhere (if you can remember) • Disadvantages • Rely on gatekeepers for content, updates • can be done on your own, hard to maintain • Still have to find them (www.yahoo.com)

  15. Search Engines • Allow searches over the text on the web • AltaVista, goto.com, Lycos, Hotbot, NetFind, WebCrawler, WebDirectory, Infoseek, etc… • Another search engine appears almost every day • Heavily automated

  16. How to Search the Web • Go to your search engine • Type in your query • Different search engines have different search syntaxes and different strengths • It is very worth it to get to know the lower level syntax of a search engine or two • The search engine checks its index of the web for hits and returns the results

  17. How a search engine works • Really a collection of several programs on several computers • Information gathering programs • Database programs • Information serving programs

  18. Information Gatherer • Automatically browses the web via “web crawling” • Indexes each page as it is found • Stores the index in a database • What if there isn’t a link to a page?

  19. Database Program • Manages many gigabytes of data • Needs to “age” data properly • Must be able to return very small bits of data very quickly • Runs on big machines optimized for input and output

  20. Information Serving Program • Often called the “front end” of the database • Searches the content with sophisticated matching algorithms • Order the results with sophisticated ordering algorithms • Formats the results into an HTML page • Hands off the page to a web-server which returns the query

  21. Search Engine Advantages • Examines large parts of the web very quickly • Gives a good “first cut” at what is out there • Really the only way to find most of what is out there • Site search engines can actually be pretty good (custom software)

  22. Search Engine Disadvantages • “Sophisticated” algorithms usually aren’t sophisticated enough • Intelligent natural-language understanding is not well understood in the CS world • 1) makes queries harder, 2) no “semantic” web • False positives and false negatives. Many don’t have useful feedback features • Effective, narrow searches are usually more inconvenient than a shotgun search and human skimming

  23. Meta Search Engines • A search engine that queries other search engines • Return results from several search engines • Have a great future? • Apple’s Sherlock, others coming

  24. Deja News • www.dejanews.com • A searchable archive of newsgroups • Very valuable resource • You can get your questions answered by the newsgroups without ever even posting • Content of the newsgroups is often quite different than the web. • More conversational, more informal.

  25. Web Portals • Starting places on the web • Excite, Yahoo, AOL, Netscape’s Home Page… • A new one pops up almost every day • Organize the web into various categories and thereby impose structure on the web • site reviews and categorization • search engine usually built in

  26. More about Web Portals • Some customization possible -- nice • Often provide teasers that are interesting • Really a play to get eyeballs for advertisers • Human intensive, hard to automate site • As smart as computers seem, there is still no substitute for humans making decisions

  27. Web Portals • Advantages • provide good organization • good news sources • eliminate crummy websites from consideration • Disadvantages • gatekeepers and judgment calls • organization still isn’t quite there • commercial motives affect content

  28. Sources and Further Reading • Picking an ISP • http://www.paintstore.com/coffeepot/column/2.html • Network Connections • http://www.brandx.net/help/selecting-data-services.html • http://www.ifl.net/support/help.html • Search Engines • http://www.searchengineguide.org/cosa.htm

  29. Project: Formica Poodles • We’re playing a search-engine game to find something out about the words on the web. • Use www.altavista.com: +word1 +word2 • Scoring? 2 x Count1 x Count2 --------------------------- (Count1 + Count2) * NumHits • Fabulous Prizes! • www-db.stanford.edu/~nsample/cs01/score.html

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