Transcript Webmaster II Webmaster Review - Fort Collins, CO

Webmaster II
Webmaster Review - Fort Collins, CO
Review
of
Webmaster I
Instructor: Joseph DiVerdi, Ph.D., MBA
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Website Purposes
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Webmaster Mission
Webmaster II
Webmaster Review - Fort Collins, CO
• Webmasters Make Sure That:
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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
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Potential Webmasters
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Evolution of Webmaster
Webmaster II
Webmaster Review - Fort Collins, CO
• “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
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Webmaster vs. Developer
Webmaster II
Webmaster Review - Fort Collins, CO
• 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"
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How the Internet Works
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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How the Internet Works
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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How the Internet Works
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Network Analogies
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Network Analogies
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Internet Addresses
Webmaster II
Webmaster Review - Fort Collins, CO
• An IP Address Uniquely Identifies a Computer
• IP Addresses Follow Dotted Decimal Notation
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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
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Domain Name System
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Domain Name Lookup
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Host & Domain Names
Webmaster II
Webmaster Review - Fort Collins, CO
• The Following Are Unique Host Names
Corresponding to Unique Computers:
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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
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Original High-level Domains
Webmaster II
Webmaster Review - Fort Collins, CO
Domain Usage
com Commercial Organizations
edu Educational Organizations
gov Non-Military Government Organizations
mil Military Organizations
org Other Organizations
net Network Resources
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Webmaster II
Webmaster Review - Fort Collins, CO
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 - Bolivia
CA - Canada
FR - France
US - USA
BR - Brazil
TD - Chad
DE - Germany
TO - Tonga
IR - Iran
IQ - Iraq
UK - UK
TW - Taiwan
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Country Domains
Webmaster II
Webmaster Review - Fort Collins, CO
• THe Following Are Unique Host Names
Corresponding to Unique Computers:
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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
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Telephone Services
Webmaster II
Webmaster Review - Fort Collins, CO
• Voice Transmission
• Fax Transmission
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Internet Services
Webmaster II
Webmaster Review - Fort Collins, CO
• World Wide Web - Hypertext Documents
– Other Services Which Use the Internet As a
Communications Medium - Nothing to Do With
the WWW
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Telnet - Login to Remote Computers
FTP - Inter-computer File Transfer
Email - Jokes for Everyone
Newsgroups - Bulletin Boards
Internet Relay Chat (IRC) - Chat Rooms
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How the WWW Works
Webmaster II
Webmaster Review - Fort Collins, CO
• 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.
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Clients and Servers
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Uniform Resource Locators
Webmaster II
Webmaster Review - Fort Collins, CO
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
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Clients & Servers
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Webmaster II
Webmaster Review - Fort Collins, CO
Browser Contacts Server (Remote Computer)
Requests Specified Document Using URL
Receives Specified Document
Renders or Displays Document on Browser
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Clients and Servers
Webmaster II
Webmaster Review - Fort Collins, CO
• 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)
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Clients and Servers
Webmaster II
Webmaster Review - Fort Collins, CO
• Upon Receiving a Request
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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)
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A Very Simple Transaction
Webmaster II
Webmaster Review - Fort Collins, CO
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Simple Transaction w/ Image
Webmaster II
Webmaster Review - Fort Collins, CO
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Site Hosting Issues
Webmaster II
Webmaster Review - Fort Collins, CO
• Basically Three Options
– Your Own Server
– Internet Service Provider (ISP)
– Presence Provider (PP)
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Site Hosting Issues
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Site Hosting Issues
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Site Hosting Issues
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Site Hosting Issues
Webmaster II
Webmaster Review - Fort Collins, CO
• 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
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Sample Site Configurations
Webmaster II
Webmaster Review - Fort Collins, CO
• Low Volume
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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.)
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Linux Operating System ($0)
Apache Server Software($0)
DSL (0.7 Mbps) (<$100/month)
Flat-file, Perl-hash, or MySQL As Database
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