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Technological standards, communicationsprotocols, security technology
Packet Switching,
Web Protocols,
HTML,
HTTP,
HTTPS and HTTS
Public and Private Key Encryption
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The Technology … Internet
Webopedia
Today’s Internet grew out of early defense anduniversity network technologies, e.g., DARPANET
The Internet is a massive network of networks, anetworking infrastructure. It connects millions ofcomputers together globally, forming a network inwhich any computer can communicate with any othercomputer as long as they are both connected to theInternet.
The Internet and the World Wide Web (aka theWeb) are not synonymous. The Internet and theWeb are two separate but related things
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The Technology … Internet
The Internet went public in 1991
The first commercial browser appeared in1994, replacing gopher or web-crawlertechnology for finding information
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The Technology …World Wide Web
The Internet and World Wide Web (a.k.a. the Web)are not synonymous. The Internet and the Webare two separate but related things.
The World Wide Web, or simply Web, is a way ofaccessing information over the medium of theInternet. It is an information-sharing model that isbuilt on top of the Internet.
•The Web uses the HTTP protocol, only one of thelanguages spoken over the Internet, to transmit data. Webservices, which use HTTP to allow applications tocommunicate in order to exchange business logic, use theWeb to share information.
•The Web also utilizes browsers to access Web documentscalled Web pages that are linked to each other viahyperlinks
Webopedia
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The Technology … TCP/IP
Transmission Control Protocol/Internet Protocol,is a suite of communications protocols used toconnect hosts on the Internet. TCP/IP the defacto standard for transmitting data overnetworks.
The IP protocol specifies the format of packets ordatagrams
TCP enables two hosts to establish a connection andexchange streams of data. TCP guarantees deliveryof data and also guarantees that packets will bedelivered in the same order in which they were sent
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Internet / Web Technology
Search engines
Portals
HyperText Markup Language (HTML)
eXtensible Markup Language (XML)
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Internet / Web Technology, Cont
Search engines
A program that searches documents for specified keywordsand returns a list of the documents where the keywordswere found.
Typically, a search engine works by sending out a spider tofetch as many documents as possible. Another program,called an indexer, then reads these documents and createsan index based on the words contained in each document.
Portals
HyperText Markup Language (HTML)
eXtensible Markup Language (XML)
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Internet / Web Technology, Cont
Search engines
Portals
Commonly referred to as simply a portal, a site or servicethat offers a broad array of resources and services, suchase-mail; information access, chat rooms, and on-lineshopping malls. The first Web portals were on-line, suchas AOL and Compu-Serve, that provided access to theinternet, but by now most of the traditional search engineshave transformed themselves into Web portals to attractand keep a larger audience.
HyperText Markup Language (HTML)
eXtensible Markup Language (XML)
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Internet / Web Technology, Cont
Search engines
Portals
HyperText Markup Language (HTML)
The authoring language used to create documents on theWorld Wide Web. HTML defines the structure and layoutof a Web document by using a variety of tags andattributes.
The correct structure for an HTML document starts with<HTML><HEAD>(enter here what document isabout)<BODY> and ends with </BODY></HTML>.
All the information you'd like to include in your Web pagefits in between the <BODY> and </BODY> tags.
eXtensible Markup Language (XML)
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Internet / Web Technology, Cont
Search engines
Portals
HyperText Markup Language (HTML)
eXtensible Markup Language (XML):
A specification developed by the World Wide WebConsortium. XML is a pared-down version of SGML,designed especially for Web documents.
XML allows designers to create their own customized tags,enabling the definition, transmission, validation, andinterpretation of data between applications and betweenorganizations.
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Metcalfe’s law
Metcalfe’s law makes e-Commerce work
Value of network proportional to n, thenumber of users: (n2 - n)/2
Increasing returns to internet users asmore join network