Transcript COS 125 day 5

COS 125
DAY 5
Agenda
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Questions from last Class??
Assignment #1 Graded
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Assignment #2 will be posted by next class
Quiz #1 on Feb 3,
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16 A’s, I non-submit
Too Easy!
20 M/C, 4 Short essays, One extra Credit
Chap 1-28
Today’s Topic
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Finish on Communicating on the Internet
Start on Using the World Wide Web
How Internet Chat works
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Live keyboard conversation on the Internet
 Most popular is Internet Relay Chat
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Chat works on Client/Server model
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Topic are channels (Chat Rooms)
Users are on clients
The chat room is on a server
There are many proprietary Chat solutions
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WebCT
How IRC works
Images from http://www.nur.ac.rw/chat.htm
Chat stuff
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Acronyms
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brb = be right back
bbl = be back later
btw = by the way
np = no problem
lol = laughing out loud
re = hi again, as in 're hi'
rotfl = rolling on the floor laughing
bbiaf = be back in a flash
ttfn = ta ta for now
imho = in my humble opinion
j/k = just kidding
wb = welcome back
Emoticons
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:) Smile
:-) Basic Smile
;-) eye wink
:-( sad
:-I Indifference
:-> Sarcastic
>:-> Diabolic
(-: left handed
%-) Drunk
8-) Uses glasses
B:-) Sunglasses on head
B-) dark sunglasses
8:-) little girl
:-{) Mustache
:-{}painted mouth
{:-)with hair
:-^) with flu
:-)^ choking
:'-( crying
:-@ shouting
:-& cant talk
-:-) punk
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|:-) fall sleep
:-O waking up
0:-) angel
:-D laughing
:-X lips seal
:-Q smoker
:-/ skeptic
C=:-) chef
@= nuclear bomb
*:O) clown
[:-) using walkman
(:I egghead
@:-) with turban
X-( just died
:] friendly smile
:D laugh
:( again sad
:O shouting
[] hugs
:* kisses
:*, ;* more kisses
:*, :*, :*, :*, more and more kisses
Instant Messaging
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Differs from chat in that it is one-to-one
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Chat one-to-many
Four popular software applications that
have little to no interoperability
MSN Messenger®
 AOL Instant Messenger®
 ICQ®
 YAHOO! Messenger®
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How Instant Messaging works
Login to messaging server (AOL, MSN)
 Send your buddy list to server
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Server tells you which of your buddies are
logged in
Select on inline buddy to talk to
Some systems connect buddy to buddy to
chat (MSN)
 Other run all chats through the server (AIM)
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How Internet Phone Calls Work
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This is using the Internet to replace the
Public Switched Telephone system
Save money on long distance
 Called Voice over IP or VoIP
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Converts Voice (analog) to digital
packets and vise versa
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Digital packets sent over the internet
PC Phones
PC to PC
PC to Regular Phone
Regular Phone to Regular Phone
Images from http://www.pc-telephone.com/
PBX-PBX IP Telephony
Ordinary
Telephone
Ordinary
Telephone
IP
Packet
Frame Relay, ATM, or
the Internet
PBX with
IP Telephony Module
PBX with
IP Telephony Module
IP Phones from Cisco
How Web Pages Work
Pages “live” on the World Wide Web
 Connected to each other using Hypertext
 Pages are written in HTML
 Works on Client/server model
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Web Site Structure
First page is called the Home Page
 Other pages are organized in one of
three possible types
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Tree
 Linear
 random
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Tree structure
Home page
page
page
page
page
page
page
page
page
page
page
page
page
Linear Structure
Home Page
Page
Page
Page
Page
Page
Random Structure
Home Page
Page
Page
Page
Page
Page
Page
Page
Page
How Web Browsers Work
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Web Browsers interpret and display web
pages
HTML
 DHTML
 XML
 Scripts
 Applications and programs
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Helper apps
 Plug-ins
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Web Browsers
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Two most popular and competitive
browsers
Internet Explorer
 Netscape Navigator
 Both have very similar features
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Web Codes
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Successful Transactions
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Redirection Transactions
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200 The request was fulfilled.
201 The POST request was completed successfully.
202 Request accepted for processing of unknown type. Rare.
203 Request partially fulfilled.
301 The requested resource has been permanently moved to a new URL. Usually accompanied by
Location: newURL which automatically connects to the new URL.
302 Requested resource found, but at a different URL. You'll get a 302 Redirection if you omit the
trailing slash when pointing at a directory (sometimes called a malformed request).
304 Unmodified data not returned in response to a GET request with the If-Modified-Since field. Occurs
when a browser requests data found in cache.
Error Messages
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400 Error in request syntax.
401 Request requires an Authorization: field, and the client did not provide one. This response is
accompanied by a list of acceptable authorization schemes use WWW-Authenticate response headers.
Error 401 can be part of a client/server dialogue to negotiate encryption and user authentication
schemes.
402 The requested operation costs money, and the client did not specify a valid Chargeto field.
403 Request for forbidden resource denied.
404 Requested resource not found.
500 The server has encountered an internal error and cannot continue processing your request.
501 Request okay but denied because server doesn't support transaction method.
How Markup Languages Work
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Markup languages contain two things
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Content
Instructions on how to format content (tags)
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Markup languages are NOT programming
languages
 3 types of markup languages exist on the
WWW
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HTML and xHTML
DHTML
XML
HTML
Uses <tags>content</tags>
 Latest version n HTML 4.01
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Full specification available at
http://www.w3.org/TR/html4/
HTML can be written with any text editor
but specialized HTML editor have been
developed
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We will be using Macromedia Dreamweaver
2004 in this class
Example HTMLs
Block Level Tags
 Text Formatting
 Using Images
 Tables
 Frames
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DHTML
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DHTML is Dynamic HTML
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Allows changes to the HTML “on the fly”
Great for animation and special effects
Uses 3 Technologies
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Document Object Model (DOM)
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Cascading Style Sheets (CSS)
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tracks every object and element on a web pages
Formatting and style information for a web pages
Client-Side Scripting
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Provide access to DOM and CSS to change them
Example DHTML
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Lots of examples available on the web
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W3Schools.com
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Olagam
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http://www.w3schools.com/dhtml/dhtml_examples.asp
http://www.olagam.com/tech3/dhtml-code.htm
Game written by COS 381 students
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http://perleybrook.umfk.maine.edu/classes/cos381/jumble
1.htm
How XML works
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Allows the creation of new markup
languages
Make your own tags that have special
meaning for a group of people
 There is no presentation information in an
XML document
 Example XML
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http://perleybrook.umfk.maine.edu/examples/planes
.xml
How XML works
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XML languages are defined in
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Data Type Definitions
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Schemas
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http://perleybrook.umfk.maine.edu/examples/planes.dtd
http://perleybrook.umfk.maine.edu/examples/planes.xsd
XML pages are formatted with
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CSS
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http://perleybrook.umfk.maine.edu/examples/planescss.xml
http://perleybrook.umfk.maine.edu/examples/planes.css
XLST
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http://perleybrook.umfk.maine.edu/examples/xslplanes.xml
http://perleybrook.umfk.maine.edu/examples/xslplanes.xsl
How XML works
DTD
Document Type
Definations
XML
Schemas
XML
Document
XSLT
Style Sheets
CSS
Browser
Display
Future of XML
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XML is the lingua franca for Net Services,
Microsoft’s .NET, Oracle, and many other
Internet based distributed architectures.
 All of HTML can be done in XML and has been
in xHTML
 XML resources
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www.xml.com
www.xml.org
http://www.w3.org/XML/
For next class
Finish reading through Chapter 28
 Assignment # 2 will be posted
 Get ready for exam on Feb 3
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