Post on 02-Jan-2016
transcript
COS 125
DAY 9
Agenda
Assignment #2 Corrected 9 A+’s, 5 A’s, 1 B, 1 C and 1 non-submit
Capstone Projects Proposals Due Timing of deliverables is 10% of Grade
Today we will discuss Multimedia on the Internet and Begin Shopping and Doing Business on the Internet We complete the HITW text this week and then
concentrate on Web Design (Castro text) for the rest of the semester
Assignments will get harder as the course progresses
Free Music File Sharing
Is it Legal? Moral? Ethical? Define your thoughts
Music & File Sharing
Hottest applications this decade Forced the music Industry to “rethink” its
distribution channels The problem
People buy CD and rip them to MP3s Not a Problem
People places these MP3 in a shareable locations Not a Problem
Other people copy the shared out MP3s Copyright violation! Buying a CD allows personal use and not redistribution
Who’s at fault?.. The person who made the MP3’s or he person that copied them?
Open debate
How KAZAA Works
KAZAA has two types of Computers PC that share out files SuperNodes that keep directories of
“who has what” Any computer that has a Broadband
connection can be a Supernode
How KAZAA works
After you download KAZAA and install You computer broadcast looking for
Supernodes When it find one it uploads your file
information When you look for a specific file you “query”
the supernode The supernodes tells your computer where you
can find the file on someone's else computer You download the file from the other computer
Kazaa Licenses
You agree not to use the Software to:
2.1 Transmit or communicate any data that is unlawful, harmful, threatening, abusive, harassing, defamatory, vulgar, obscene, invasive of another's privacy, hateful, or racially, ethnically or otherwise objectionable;
2.2 Harm minors in any way;
2.3 Impersonate any person or entity or falsely state or otherwise misrepresent your affiliation with a person or entity;
2.4 Forge headers or otherwise manipulate identifiers in order to disguise the origin of any data transmitted to other users;
2.5 Transmit, access or communicate any data that you do not have a right to transmit under any law or under contractual or fiduciary relationships (such as inside information, proprietary and confidential information learned or disclosed as part of employment relationships or under non-disclosure agreements);
2.6 Transmit, access or communicate any data that infringes any patent, trademark, trade secret, copyright or other proprietary rights of any party;
2.7 Transmit or communicate any data that contains software viruses or any other computer code, files or programs designed to interrupt, destroy or limit the functionality of any computer software or hardware or telecommunications equipment;
Kazaa in the media
http://www.wired.com/wired/archive/11.02/kazaa.html
http://news.com.com/2100-1023-920557.html http://www.business2.com/b2/web/articles/0,1786
3,515871,00.html http://www.cnn.com/2003/TECH/internet/09/09/m
usic.swap.settlement/ http://www.pbs.org/newshour/media/medi
a_watch/jan-june04/riaalawsuits_01-21.html
Napster
NapsterIndex Server
2.Search Query
3.Response
1.Uploads List
Of Available FilesWhen Connects
4.Large P2PDownload
File List
List ofAvailable
FilesFrom All
Current Clients
Client PC Client PC Client PC
How Video on the Internet Works
Three methods of delivery Multicast (MBone) Streaming Video Videoconference
Requires webCam
How Streaming Video Works
Same as Streaming Audio Streaming is playing and
downloading a file at the same time As soon as enough of the file has been
downloaded… the applications will begin to play the file and hope the rest gets there in time
Demo from Learn The Net
Video Conferencing
Many Software solutions for Video Conferencing
Netmeeting built into Windows 2000 Windows XP Just add
WebCam Microphone
Works on H.323
WebCams
Small Digital cameras Best ones work on USB 2.0 Avoid Parallel port versions
Used to create videos
Multicast and MBone
Video files and stream tend to be very large What happens when thousands of
people want to see the same video at the same time
Video 100MB * 10,000 viewers We need 1000 GB of band width at the
source of the video A better way?
Think of how cable TV works
Multicasting
What would happen if the server sent one copy of the video file to each location that had users and let the routers make individual copies for each user
Each multicast router copies the files and send copies to each network that requires the file
Source only has to send one file Multicast routers handle the individual users
Unicast ---------------------Multicast
Virtual Reality
3-D illusion in 2-D space Requires special plug-ins or browser
How VRML works
VRML code is plain (ASCII) text. The code describes object(s) attributes, such as, geometry,
size, color, textures and location within the virtual world. In order to view VRML scenes you must have a VRML capable
browser. Usually an add-on plug-in or a browser designed for VRML.
When a user encounters VRML on a website the browser receives instructions from the server on the other end.
The server sends VRML code to the user's browser. The VRML viewer then interprets the instructions and displays the scene.
Downloaded VRML text files are interpreted locally, on the users computer, by the VRML player and rendered in real-time by the CPU.
The files range in size from under 100 kb to several megabytes, so bandwidth directly effects download or access time.
Once the world is loaded, the user's experience is dictated by the CPU performance. High performance processors allow faster and smoother navigation through VRML world
Animations on the Web
Animation are still as the began Series of pictures that are slightly different that
are displayed one after another Different ways of accomplishing this
technique on the web Client Pull Server Push Animated Gifs Macromedia Shockwave Macromedia Flash
Client Pull
The clients loads the first picture in the series and sets a timer Then load the second Then the third
Uses special “Meta” refresh tag in HTML
Very Slow example
Server Push
Web Server pushes new pictures in the series to the browser Only works in Netscape Requires especial server side
programming Nobody uses it any more
Animated Gifs
Probably the easiest way to create an animation Lots of free tools available
http://www.mindworkshop.com/alchemy/alchemy.html
http://www.jasc.com/download_4.asp? We will be using Paint Shop Pro in this
class Example
http://perleybrook.umfk.maine.edu/classes/cos125/samples/aGif.htm
Macromedia
Macromedia Software Shockwave Flash
These are classes all by themselves Examples
http://perleybrook.umfk.maine.edu/samples/umfkLOGo.html
http://www.cyberdimmensions.com/flash/presentation.html
http://www.cyberdimmensions.com/flash/weis_l9_rocketlaunch6.html