SM2215 Genres Part 3 – The Internet Mark Green School of Creative Media

SM2215 GenresSM2215 GenresPart 3 – The InternetPart 3 – The Internet

Mark GreenMark Green

School of Creative MediaSchool of Creative Media

IntroductionIntroduction

The Web is the main form of Internet The Web is the main form of Internet media, but there are other formsmedia, but there are other forms

Many of these forms are accessed through Many of these forms are accessed through a browser, so they are often confused with a browser, so they are often confused with the Webthe Web

Look at some of the more popular forms Look at some of the more popular forms and their artistic, cultural and political and their artistic, cultural and political applicationsapplications

Streaming MediaStreaming Media

Started with compressionStarted with compression Compressed video and audio, more Compressed video and audio, more

efficient to send over network, basic file efficient to send over network, basic file transfertransfer

If compression is good enough can If compression is good enough can transfer in real time, a second of media transfer in real time, a second of media can be transferred in less than a secondcan be transferred in less than a second

Only need to reconstruct itOnly need to reconstruct it


Two things are required:Two things are required: Real time transferReal time transfer Real time reconstructionReal time reconstruction

The un-compression algorithm must be The un-compression algorithm must be fast enough to run in real timefast enough to run in real time

Be able to transmit and reconstruct the Be able to transmit and reconstruct the signal at the same rate it should be playedsignal at the same rate it should be played


Two modes of operation:Two modes of operation: On demandOn demand LiveLive

On demand: client connects to server and On demand: client connects to server and requests a particular media cliprequests a particular media clip

Server then streams the clip to the clientServer then streams the clip to the client Only two parties involved in the transferOnly two parties involved in the transfer


Live: server is broadcasting a live event to Live: server is broadcasting a live event to a group of clientsa group of clients

Event could be an Internet radio station or Event could be an Internet radio station or a sports eventa sports event

The media hasn’t been previously The media hasn’t been previously recorded, it is being sent as it is generatedrecorded, it is being sent as it is generated

many clients getting the same content at many clients getting the same content at the same timethe same time


On demand is easier and can be higher On demand is easier and can be higher qualityquality

Can preprocess the media, just transmit to Can preprocess the media, just transmit to single client when requestedsingle client when requested

Can adjust quality to available network Can adjust quality to available network bandwidth, tune the transmission to what bandwidth, tune the transmission to what the network can deliverthe network can deliver


Live involves the server sending a real Live involves the server sending a real time stream to many clientstime stream to many clients

Server must compress the stream as it Server must compress the stream as it occurs in real timeoccurs in real time

Then needs to send to all of the clientsThen needs to send to all of the clients Can require much more bandwidth and Can require much more bandwidth and

can’t tune the transmission to each client’s can’t tune the transmission to each client’s network connectionnetwork connection


Live broadcasts can go to thousands of Live broadcasts can go to thousands of clients, can’t have a separate connection clients, can’t have a separate connection for each clientfor each client

Multicasting allows server to send one Multicasting allows server to send one copy, automatically routed to the clients copy, automatically routed to the clients that want itthat want it

Much more efficient use of network Much more efficient use of network bandwidthbandwidth

Pirate RadioPirate Radio

Unlicensed radio stations:Unlicensed radio stations: No government controlNo government control No royalties paid to record companiesNo royalties paid to record companies

Quite an old idea, based on low power Quite an old idea, based on low power transmitters that are easy to movetransmitters that are easy to move

Most countries will try to shut down pirate Most countries will try to shut down pirate radio stations, often work off shoreradio stations, often work off shore


Why?Why? Political message not popular with current Political message not popular with current

governmentgovernment Music that isn’t popular on commercial radioMusic that isn’t popular on commercial radio Grass roots access to mediaGrass roots access to media FunFun

Transmitter based can be dangerous and Transmitter based can be dangerous and difficult, moving to network radiodifficult, moving to network radio


Stream from a server, could be a Stream from a server, could be a connection from a web page, or IP connection from a web page, or IP address distributed by emailaddress distributed by email

Server can be in different country, or Server can be in different country, or moved regularly to prevent blockingmoved regularly to prevent blocking

Harder to find and shut down than Harder to find and shut down than transmitter based stationstransmitter based stations

Web RadioWeb Radio

Regular radio has limited range, can only Regular radio has limited range, can only reach local listenersreach local listeners

must be able to get large audience from must be able to get large audience from local arealocal area

may not be possible for some types of may not be possible for some types of musicmusic

music styles vary from one part of the music styles vary from one part of the world to anotherworld to another

Web RadioWeb Radio

Web radio removes regional restrictions, Web radio removes regional restrictions, much larger population to draw onmuch larger population to draw on

two main implications:two main implications: can build up audience for less popular stylescan build up audience for less popular styles reach listeners outside of normal geographical reach listeners outside of normal geographical

areaarea can be exposed to a wider range of culturescan be exposed to a wider range of cultures can send our culture furthercan send our culture further

Web RadioWeb Radio

Issues:Issues: are advertisers willing to pay? Most radio ads are advertisers willing to pay? Most radio ads

are local, need to look at global audienceare local, need to look at global audience royalties, where are they paid, who gets royalties, where are they paid, who gets

them?them? How do we measure audience size, this is How do we measure audience size, this is

important for advertising and royaltiesimportant for advertising and royalties how should web radio be funded? Is how should web radio be funded? Is

advertising the right modeladvertising the right model

Business ModelsBusiness Models

How do we make money on internet How do we make money on internet services?services?

Advertising is the broadcast / print media Advertising is the broadcast / print media solution, is it best for the internet?solution, is it best for the internet?

Many sites use various forms of Many sites use various forms of advertising and click throughsadvertising and click throughs

seems to work for a few very popular sitesseems to work for a few very popular sites


Problems with advertising:Problems with advertising: software to remove adverts, not sure that user software to remove adverts, not sure that user

ever sees themever sees them developing a negative image, too much will developing a negative image, too much will

chase users awaychase users away hard to measure number of viewers, standard hard to measure number of viewers, standard

charging mechanism for advertscharging mechanism for adverts how do local advertisers fit into the picture?how do local advertisers fit into the picture?


Other possible models:Other possible models: sponsorship, have a small number of large sponsorship, have a small number of large

companies sponsor the web site, minimal companies sponsor the web site, minimal advertisingadvertising

subscription, each viewer pays a certain subscription, each viewer pays a certain amount per year, best if voluntaryamount per year, best if voluntary

donations and annual appeals, has worked donations and annual appeals, has worked well for public broadcasting in North Americawell for public broadcasting in North America

Peer to PeerPeer to Peer

Most Internet services are based on the Most Internet services are based on the client-server modelclient-server model

There is a server that contains the There is a server that contains the information, multiple clients connect to it to information, multiple clients connect to it to receive informationreceive information

The server is the central resource, stores The server is the central resource, stores all of the informationall of the information

Server Model Server Model

Server

client

client client

client

Server ModelServer Model

Encourages broadcast, central server has Encourages broadcast, central server has all the content, sent to the clients on all the content, sent to the clients on requestrequest

clients have no contentclients have no content the server controls the interaction, the the server controls the interaction, the

client plays a more passive roleclient plays a more passive role

Peer to PeerPeer to Peer

In the peer to peer model there is no In the peer to peer model there is no central server, or its plays a minimal rolecentral server, or its plays a minimal role

The clients are directly connected together The clients are directly connected together and share informationand share information

More of a two way flow of information, no More of a two way flow of information, no centralized coordination, no special nodes centralized coordination, no special nodes in the systemin the system

Peer to Peer ModelPeer to Peer Model

client

client

client

client client

Peer to Peer ModelPeer to Peer Model

More of a communications modelMore of a communications model one node doesn’t have control over the one node doesn’t have control over the

content, no monopoly on contentcontent, no monopoly on content all nodes contribute to the contentall nodes contribute to the content applications tend to concentrate on applications tend to concentrate on

communications, tend to be real time communications, tend to be real time interactiveinteractive

How is it Used?How is it Used?

Most high profile use is file sharing, Most high profile use is file sharing, originated with Napster, but there are originated with Napster, but there are other applications:other applications: file sharingfile sharing resource sharingresource sharing communicationscommunications

File SharingFile Sharing

Napster allowed people to exchange MP3 Napster allowed people to exchange MP3 files, share their music files with othersfiles, share their music files with others

each user had a library of music files that each user had a library of music files that they could sharethey could share

problem was finding who had what fileproblem was finding who had what file Napster used a centralized model, a Napster used a centralized model, a

server maintained a list of who had which server maintained a list of who had which filesfiles


To find a file, send a message to the To find a file, send a message to the serverserver

server responds with list of people with the server responds with list of people with the filesfiles

connect to one of these computers, connect to one of these computers, directly transfer the file from that computerdirectly transfer the file from that computer

Napster server never stored any MP3 files, Napster server never stored any MP3 files, just served as a directory or search enginejust served as a directory or search engine


Napster system had two benefits:Napster system had two benefits: no storage of MP3 files meant they were not no storage of MP3 files meant they were not

directly guilty of copyright infringementdirectly guilty of copyright infringement did not need all of the disk space to store all did not need all of the disk space to store all

the filesthe files Napster still had major legal problems, but Napster still had major legal problems, but

formed the model for future systemsformed the model for future systems


Napster wasn’t the first file sharing Napster wasn’t the first file sharing system, Usenet started in 1979, used for system, Usenet started in 1979, used for both messaging and file sharingboth messaging and file sharing

based on newsgroups, each group is a based on newsgroups, each group is a sequence of messages on similar topicssequence of messages on similar topics

newsgroups forms a hierarchy, but rarely newsgroups forms a hierarchy, but rarely more than 3 or 4 levelsmore than 3 or 4 levels


New newsgroups are formed by a New newsgroups are formed by a democratic processdemocratic process

group is proposed and anyone with an group is proposed and anyone with an email account can vote on its creationemail account can vote on its creation

if vote passed, newsgroup is createdif vote passed, newsgroup is created in the alt hierarchy anyone can create a in the alt hierarchy anyone can create a

new group, a form of organized anarchynew group, a form of organized anarchy


Usenet has no central server, no central Usenet has no central server, no central storagestorage

every system on Usenet exchanges every system on Usenet exchanges messages with the systems it is directly messages with the systems it is directly connected to, messages spread over connected to, messages spread over UsenetUsenet

message header ensure messages aren’t message header ensure messages aren’t sent back to systems that already have sent back to systems that already have themthem


Gnutella and similar systems get around Gnutella and similar systems get around one of Napster’s problemsone of Napster’s problems

no central server with file directory, the no central server with file directory, the directory is shared by all the clientsdirectory is shared by all the clients

each client maintains list of other Gnutella each client maintains list of other Gnutella clients it knows about, can change clients it knows about, can change dynamically dynamically


To find a file, send a message to other To find a file, send a message to other clients on our listclients on our list

if a client has the file, responds with its if a client has the file, responds with its address, otherwise it passes the request address, otherwise it passes the request on to all the the clients it knows ofon to all the the clients it knows of

eventually will get responses with the eventually will get responses with the clients that have file (if it exists anywhere clients that have file (if it exists anywhere on the network)on the network)

Resource SharingResource Sharing

Can share more than files, can also share Can share more than files, can also share computer timecomputer time

most of the time home computers aren’t most of the time home computers aren’t used, they are idle, could be used for other used, they are idle, could be used for other purposespurposes

the basic idea behind the SETI@home the basic idea behind the SETI@home programprogram


SETI is the search of extra terrestrial SETI is the search of extra terrestrial intelligenceintelligence

based on recording signals from radio based on recording signals from radio telescopes and then trying to find telescopes and then trying to find intelligence in them, some form of intelligence in them, some form of communicationscommunications

requires very large amounts of requires very large amounts of computation, not available to researcherscomputation, not available to researchers


SETI@home uses home computers to SETI@home uses home computers to process the dataprocess the data

home computer requests a small part of home computer requests a small part of the data, analyzes the data, and sends the the data, analyzes the data, and sends the results back to central site, repeats results back to central site, repeats processprocess

large network of home computers is more large network of home computers is more powerful than largest computers, and its powerful than largest computers, and its freefree


Possible model for funding network servicesPossible model for funding network services provide a few hours of computing time in provide a few hours of computing time in

exchange for a service, i.e. web radioexchange for a service, i.e. web radio some large computations are commercially some large computations are commercially

important, companies will pay for timeimportant, companies will pay for time sponsor services in exchange for sponsor services in exchange for

computationscomputations

CommunicationsCommunications

Instant messaging and similar systems Instant messaging and similar systems provide a form of peer to peer provide a form of peer to peer communicationscommunications

most of these systems are at least partially most of these systems are at least partially server based, but they support server based, but they support communications between two or more communications between two or more clientsclients

in real time they can be peer to peerin real time they can be peer to peer


Why do they need a server?Why do they need a server? Need to know how to contact other users, can Need to know how to contact other users, can

roam between computersroam between computers need to know who is onlineneed to know who is online store messages for users who aren’t currently store messages for users who aren’t currently

onlineonline except for last point, the server can play a except for last point, the server can play a

rather minor rolerather minor role


Without message storage, server only Without message storage, server only needs to know who is connected and how needs to know who is connected and how they can be contactedthey can be contacted

this could probably be distributed in the this could probably be distributed in the same way as Gnutella, broadcast requests same way as Gnutella, broadcast requests to known clients, etcto known clients, etc

once friend is found directly connect to once friend is found directly connect to their clienttheir client


Most instant messaging systems are Most instant messaging systems are commercial:commercial: server based, can keep track of users, server based, can keep track of users,

charging is possiblecharging is possible proprietary protocols, can only talk to people proprietary protocols, can only talk to people

on the same system, can’t send messages on the same system, can’t send messages between systemsbetween systems

most systems are limited to textmost systems are limited to text


Jabber: Open source protocol for instant Jabber: Open source protocol for instant messagingmessaging

originally developed as a bridge between originally developed as a bridge between other instant messaging systemsother instant messaging systems

Jabber can support other media, such as Jabber can support other media, such as sound and video, not clear whether any of sound and video, not clear whether any of the standard clients support thisthe standard clients support this

could develop custom clients for art could develop custom clients for art projectsprojects

Social and Political IssuesSocial and Political Issues

Sometime a political agenda associated Sometime a political agenda associated with these serviceswith these services

political commentary in countries with tight political commentary in countries with tight media controlmedia control

expression of unpopular opinions, possible expression of unpopular opinions, possible legal or economic problems associated legal or economic problems associated with viewswith views


Two main concerns:Two main concerns: censorship of online information sourcescensorship of online information sources anonymity for controversial messagesanonymity for controversial messages

with a central server its very easy to block with a central server its very easy to block messages and web content, domain name messages and web content, domain name and IP are well knownand IP are well known

with many peers this isn’t possible, IP can with many peers this isn’t possible, IP can change dynamically from day to daychange dynamically from day to day


Only problem is knowing the current IP Only problem is knowing the current IP address, this can be done through email or address, this can be done through email or through a broadcast mechanism like through a broadcast mechanism like GnutellaGnutella

anonymous mailing systems make it anonymous mailing systems make it impossible or difficult to trace origin of impossible or difficult to trace origin of messages, can be used to hide the messages, can be used to hide the author’s identityauthor’s identity


With regular email can trace the author, With regular email can trace the author, can trace message back to machine can trace message back to machine where the message was createdwhere the message was created

to send an anonymous message, send to to send an anonymous message, send to a special server, hides sender’s identitya special server, hides sender’s identity

can even reply to anonymous email, can even reply to anonymous email, through the same server that sent itthrough the same server that sent it


Can be used to protect people with Can be used to protect people with important, but sensitive messages, assist important, but sensitive messages, assist political groups, etcpolitical groups, etc

but, there is a negative side, same but, there is a negative side, same technology can be used by terrorists and technology can be used by terrorists and criminalscriminals

can also be used to hide their activities, can also be used to hide their activities, becomes a moral and ethical issuebecomes a moral and ethical issue

Artistic ApplicationsArtistic Applications

Can we use this technology in an artistic Can we use this technology in an artistic way?way?

There are at least two applications:There are at least two applications: broadcast, distribution of art workbroadcast, distribution of art work collaboration and performancecollaboration and performance

Napster used to distribute commercial Napster used to distribute commercial MP3s, why not use it to distribute other art MP3s, why not use it to distribute other art works?works?


Could use file sharing systems to Could use file sharing systems to distribute video and music piecesdistribute video and music pieces

no need to have formal distribution no need to have formal distribution channels, good for new artists and less channels, good for new artists and less popular art formspopular art forms

avoid issues of censorship and artistic avoid issues of censorship and artistic tastestastes


Instant messaging for artistic purposes?Instant messaging for artistic purposes? Be able to collaborate in real time on Be able to collaborate in real time on

creation of artistic piecescreation of artistic pieces easy to see with text, but this might not be easy to see with text, but this might not be

the most interestingthe most interesting adding sound and video gives a much adding sound and video gives a much

richer environment, could use the same richer environment, could use the same technologytechnology

Documents

SM2215 Genres Part 3 – The Internet Mark Green School of Creative Media