1. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Review of Webmaster I Instructor: Joseph DiVerdi, Ph.D., MBA

2. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Website Purposes Individuals, Organizations, Businesses Rely on Web Pages –Provide and Collect Information –Manage Processes –Interact With Communities and Customers Reliable, Informative, & Responsive Web Site –Creates a Positive Image –Increases Visibility –Manages Cost

3. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Webmaster Mission Webmasters Make Sure That: –The Information on a Site Is Accessible –The Information on a Site Is Usable –The Site Is Always Available –The Performance Is Good –Users Can Get Needed Information –The Site Can Collect the Information It Needs Whatever It Takes to Accomplish These Goals –Legally, Ethically, & Morally

4. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Potential Webmasters Content Providers Work on the Data Itself, Creating or Editing HTML Documents, Incorporating Images & Forms, & Maintaining the Integrity of the Links Designers Create the Images & Also Define the “Look” of the Site Programmers Write CGI, Perl, Java, JavaScript, & Other Programs for Incorporation Into the Site Administrators Make Sure That the Server Runs Properly & Efficiently at All Times, They Might Also Be for Writing New Scripts & Maintaining Document and Site Security

5. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Evolution of Webmaster “Webmaster” Is Now Too Big for One Person It Is Supplemented by Other Titles –Internet Strategist Develops, Executes, & Manages Strategy for Use of Internet Technologies in Support of Corporate Initiatives –Electronic Commerce Manager Develops, Drives, Executes, & Manages Internet Commerce for a Business Unit –Internet Strategy Director Develops & Implements a Wide Range of Internet Strategies to Meet Company Business Objectives

6. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Webmaster vs. Developer Webmasters' Responsibilities Are Broader Than Web Developers' –Webmasters Are Expected to Understand the Web to a Greater Technical Degree Than Are Web Developers –Web Developers Often Are Expected to Understand Content to a Greater Degree Webmasters Often Perform Web Development Webmasters Often Are "Jacks of All Trades"

7. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC How the Internet Works The Internet Is a Communications Medium Through Which Information Is Transferred Between Computers –Many Different Services Use the Internet for Transferring Information They Most Often Use TCP/IP to Transfer Data –Transmission Control Protocol/internet Protocol The Telephone Network Is Also a Communications Medium but With Very Different Characteristics

8. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC How the Internet Works The Internet Is a Packet Switched Network –When Data Leaves the Source Computer It Is Broken up Into Packets Small Chunks of Data –Transmitted Through Larger and Larger Networks Usually 1-1,500 Bytes Long Packets Are Routed Through Many Networks When the Packets Arrive at the Destination Computer –They Are Reassembled Into the Original Message

9. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC How the Internet Works Breaking the Data up Into Small Packets –Increases the Efficiency of the Whole Network –Exact Path Taken From the Same Source to the Same Destination Is Often Different Path Depends on the Instantaneous Load –On Each of the Routers & Networks Packet Data Is Identified by the Internet Addresses –Of the Source & Destination Computers

10. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Network Analogies US Postal Service Is a Packet Switched Network –No User Receives a Dedicated Piece of the Network Routers Are Equivalent to Postal Substations –Mail Sent From Milford, CT to Loveland, CO Does Not Use a Reserved Plane or Truck It Is Pooled at a Substation & Sent to a Series of Substations Efficient Utilization of Network Resources

11. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Network Analogies Telephone Network Is a Circuit Switched Network –When a Telephone Call Is Made a Piece of the Network Is Dedicated to That Call Even If That Piece Isn't Being Used –Being on Hold –That Piece of the Network Is Unavailable for Use by Others Inefficient Utilization of Network Resources

12. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Internet Addresses An IP Address Uniquely Identifies a Computer IP Addresses Follow Dotted Decimal Notation –Four Decimal Numbers –Each Ranging From 0 to 255 –Each Number Separated by a Period –The Following Are Unique IP Addresses and Corresponding to Unique Computers: 206.168.235.2 192.122.36.5 128.174.5.6 IP Addresses Are Registered & Allocated

13. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Domain Name System A Host Name Is Assigned to Each Computer Only for the Convenience of Human Users –Computers Refer to Each Other by IP Addresses Host Names Use a Hierarchical Domain Structure –Right-to-left Most-to-least Significant –Each Domain Is Separated by a Period Host Names Are Registered & Allocated –By a Central Authority

14. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Domain Name Lookup Convert a Domain Name Into an IP Address Use DNS Servers –Computers Whose Sole Purpose Is to Maintain Lists of IP Addresses and Domain Names Local DNS Servers Know Local Addresses –DNS Servers Cache Recently Requested Addresses Local DNS Servers Also Know Addresses of More-Significant Domain Name Servers

15. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Host & Domain Names The Following Are Unique Host Names Corresponding to Unique Computers: –woody.xtrsystems.com –lamar.colostate.edu –holly.colostate.edu –nic.ddn.mil –whitehouse.gov –uxc.cso.uiuc.edu –linus.ulltra.com One Computer May Have Several Host Names

16. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Original High-level Domains DomainUsage comCommercial Organizations eduEducational Organizations govNon-Military Government Organizations milMilitary Organizations orgOther Organizations netNetwork Resources

17. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Country Domains The Internet Is a World-Wide Network Foreign (Relative to the USA) Countries Have Responsibility for Their Own Names Country Codes Are a Set of Two Letter Highest-level Country Domains About 300 Country Codes Exist BO - BoliviaBR - BrazilIR - Iran CA - CanadaTD - ChadIQ - Iraq FR - FranceDE - GermanyUK - UK US - USATO - TongaTW - Taiwan

18. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Country Domains THe Following Are Unique Host Names Corresponding to Unique Computers: –hockey.guelph.ca –alpha.psd.k12.co.us –ci.fort-collins.co.us –uxc.urbana.il.us Host Names Are Registered & Allocated –By Central Authorities

19. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Telephone Services Voice Transmission Fax Transmission

20. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Internet Services World Wide Web - Hypertext Documents –Other Services Which Use the Internet As a Communications Medium - Nothing to Do With the WWW Telnet - Login to Remote Computers FTP - Inter-computer File Transfer Email - Jokes for Everyone Newsgroups - Bulletin Boards Internet Relay Chat (IRC) - Chat Rooms

21. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC How the WWW Works The World Wide Web Is an Information Service That Uses the Internet As Its Communication Medium –It Is Based on the Technology Called Hypertext Hypertext Is a Method of Presenting Information Selected Words in a Text Can Be "Expanded" –To Provide Other Information About the Word –These Words Are Called Links to Other Documents Text, Images, Sounds, etc.

22. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Clients and Servers The Web Browser on Your Desktop Is a Web Client –Navigator, Explorer, Opera, Mosaic, Etc. Most Common Interface to the WWW To Request a Document With a Browser It Needs a Universal Resource Locator (URL) URL Identifies Computer With Information URL Identifies Path to the Document

23. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Uniform Resource Locators http://perl.oreilly.com/news/2000_june.html scheme://host/path Scheme : the Protocol That Connects to the Site Host : the Name of the Server to Connect Path : the Location in the Server’s Directory Tree

24. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Clients & Servers Browser Contacts Server (Remote Computer) Requests Specified Document Using URL Receives Specified Document Renders or Displays Document on Browser

25. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Clients and Servers A Server Is a Computer Running Server Software –Apache A Server –Sits Patiently Running Server Software –Listening to Its Internet Connection –Awaiting Requests Uses Hyper Text Transfer Protocol (HTTP)

26. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Clients and Servers Upon Receiving a Request –Accepts URL Path –Converts Path Into File Name –Returns Status to Requesting IP Address –Returns File to Requesting IP Address, If Found Uses Hyper Text Transfer Protocol (HTTP)

27. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC A Very Simple Transaction

28. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Simple Transaction w/ Image

29. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Site Hosting Issues Basically Three Options –Your Own Server –Internet Service Provider (ISP) –Presence Provider (PP)

30. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Site Hosting Issues Internet Service Provider (ISP) –A Service From a Company That Houses Its Own Server Computers Which Rents Out Bits of Them on a Monthly Fee Basis –ISP Supplies Internet Connection & Sys Admin –Sys Admin Maintains Hardware You Call & Complain –You Access Through Your Own Internet Connection Which You Must Purchase Through an ISP

31. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Site Hosting Issues Presence Provider (PP) –A Service From a Company That Houses Its Own Server Computers Which Rents Out Bits of Them on a Monthly Fee Basis –ISP Supplies Internet Connection & Sys Admin –Sys Admin Maintains Hardware You Call & Complain –You Access Through Your Own Internet Connection Which You Must Purchase Through an ISP

32. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Site Hosting Issues Your Own Server –When You’re Really Big Or Tired of Using an ISP –You Must Supply a Dedicated Internet Connection DSL, T1, T3, etc. –You Must Supply One or More Dedicated Computers –You Must Supply Real System Administrator(s) –You Access Directly

33. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Site Hosting Issues In This Class You Will Use “Local Hosting” –Viewing Web Pages Using a Web Client on the Same Computer Without Any Server You Will Also Use "Remote Hosting" –You Will Be Assigned a Linux Account –On a Server Here at Ulltra Technology Corp. –You Can & Will Access Your Account From Any Computer With an Internet Connection –You Can & Will Develop Your Web Site From Any Computer With an Internet Connection

34. Webmaster II Webmaster Review - Fort Collins, CO Copyright © XTR Systems, LLC Sample Site Configurations Low Volume –1,000 - 10,000 Hits Per Day –0.01 - 0.1 Hits Per Second - Average –0.1 - 1.0 Hits Per Second - Peak –Can Be Run Out of The Home (Office) –Good Intel (486, Pentium I) Hardware ($200) Or AMD Equivalent (K6, Athlon, etc.) –Linux Operating System ($0) –Apache Server Software($0) –DSL (0.7 Mbps) (<$100/month) –Flat-file, Perl-hash, or MySQL As Database