7. www internet service provider (isp) e.g. aol, freeserve internet service provider (isp) e.g. aol,...
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7. WWW
InternetService
Provider (ISP)E.g. AOL, Freeserve
InternetService
Provider (ISP)E.g. AOL, Freeserve
ISDN(64kbps/128kbps)
Modem(28.8/56kbps)
Router(T1 - 1.544Mbps)
Internet
Router(Frame Relay: 256kbps)
Local Area Network
7.1 WWW operation
HTML/JavaHTML/Java
WWW server
WWW server
WWW browser
HTTP protocol
WWW browser
HTTPHTTP
TCPTCP
IPIP
HTTP protocolHTML/Java WWW page
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Internet(TCP/IP)
7.2 WWW Topology
Germany
Japan
UK
USA
France
UserLinksto otherWeb servers
Sweden
Canada
HyperText
Language
HyperText
Language
HyperText
Language
HyperText
Language
HyperText
Language
HyperText
Language
HyperText
Language
7.3 Advantages/Disadvantages of the WWWGlobal information flow
Less control of information by the media, governments and large organisations.
Lack of control on criminal material, such as certain types of pornography and terrorist activity.
Global information flow Less control of information by the media,
governments and large organisations. Lack of control on criminal material, such
as certain types of pornography and terrorist activity.
Global transmission Communication between people and
organisations in different countries which should create the Global Village.
Data can easily get lost or state secrets can be easily transmitted over the world.
Global transmission Communication between people and
organisations in different countries which should create the Global Village.
Data can easily get lost or state secrets can be easily transmitted over the world.
Internet connections Many different types of connections are
possible, such as dial-up facilities (perhaps over a modem or with ISDN) or through frame relays. The user only has to pay for the service and the local connection.
Data once on the Internet is relatively easy to tap into and possibly easy to change.
Internet connections Many different types of connections are
possible, such as dial-up facilities (perhaps over a modem or with ISDN) or through frame relays. The user only has to pay for the service and the local connection.
Data once on the Internet is relatively easy to tap into and possibly easy to change.
Global information Creation of an ever-increasing global
information database. Data is relatively easy to tap into and
possibly easy to change.
Global information Creation of an ever-increasing global
information database. Data is relatively easy to tap into and
possibly easy to change.
Increasing WWW usage Helps to improve its chances of
acceptance into the home. Increased traffic swamps the global
information network and slows down commercial traffic.
Increasing WWW usage Helps to improve its chances of
acceptance into the home. Increased traffic swamps the global
information network and slows down commercial traffic.
Multimedia integration Tailor-made applications with good
presentation tools. Lack of editorial control leads to inferior
material, which is hacked together.
Multimedia integration Tailor-made applications with good
presentation tools. Lack of editorial control leads to inferior
material, which is hacked together.
WWW links Easy to set up and leads users from one
place to the next in a logical manner. WWW links often fossilise where the link
information is out-of-date or doesn’t even exist.
WWW links Easy to set up and leads users from one
place to the next in a logical manner. WWW links often fossilise where the link
information is out-of-date or doesn’t even exist.
Education Increased usage of remote teaching with
full multimedia education. Increase in surface learning and lack of
deep research. It may lead to an increase in time-wasting (too much surfing and too little learning).
Education Increased usage of remote teaching with
full multimedia education. Increase in surface learning and lack of
deep research. It may lead to an increase in time-wasting (too much surfing and too little learning).
7.4 Example Connections to the Internet
InternetService
Provider (ISP)E.g. AOL, Freeserve
InternetService
Provider (ISP)E.g. AOL, Freeserve
ISDN(64kbps/128kbps)
Modem(28.8/56kbps)
Router(T1 - 1.544Mbps)
Internet
Router(Frame Relay: 256kbps)
Local Area Network
7.5 URLs
<Protocol><Server name><Path name><Filename>
+ http (hypertext transmission protocol)
aaaa:bbb.bbb.bbb/ccc/ccc/ccc?dddd
+ ftp (file transfer protocol)
+ https (secure hypertext transmission protocol)
+ mailto (mail to)
+ telnet (remote login program)
+ news (news server)
+ Server name (e.g www.intel.com)
+ File path name
+ Additional
Examplesmailto:fred.bloggs.co.ukhttp://www.intel.com/search/
index.htmlftp://anonymous:[email protected]/
src/info.txttelnet://
fred:[email protected]/
Examplesmailto:fred.bloggs.co.ukhttp://www.intel.com/search/
index.htmlftp://anonymous:[email protected]/
src/info.txttelnet://
fred:[email protected]/
7.6 WWW browser design
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