History and Backgound: Internet & Web 2.0

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1 1 History and Backgound: Internet & Web 2.0 History of the Internet and World Wide Web 2 ARPANET Implemented in late 1960 s by ARPA (Advanced Research Projects Agency of DOD) Networked computer systems of a dozen universities and institutions with 56KB communications lines Grandparent of today s Internet Intended to allow computers to be shared Became clear that key benefit was allowing fast communication between researchers electronic-mail ( )

2 History of the Internet and World Wide Web ARPA s goals Allow multiple users to send and receive info at same time Network operated packet switching technique - Digital data sent in small packages called packets - Packets contained data, address info, error-control info and sequencing info - Greatly reduced transmission costs of dedicated communications lines Network designed to be operated without centralized control - If portion of network fails, remaining portions still able to route packets 3 History of the Internet and World Wide Web Transmission Control Protocol (TCP) Name of protocols for communicating over ARPAnet Ensured that messages were properly routed and that they arrived intact Organizations implemented own networks Used both for intra-organization and communication 4

3 History of the Internet and World Wide Web Huge variety of networking hardware and software appeared ARPA achieved inter-communication between all platforms with development of the IP - Internetworking Protocol - Current architecture of Internet Combined set of protocols called TCP/IP The Internet Limited to universities and research institutions Military became big user Next, government decided to access Internet for commercial purposes 5 Personal, Distributed and Client/Server Computing Apple Computer popularized personal computing Computers became economical for personal or business use Machines could be linked together in computer networks Local area networks (LANs) Distributed computing Workstations Servers offer data storage and other capabilities that may be used by client computers distributed throughout the network, Client/server computing Popular operating systems UNIX, Linux, Mac OS X and Microsoft s Windows

4 History of the Internet and World Wide Web Internet traffic grew Businesses spent heavily to improve Internet - Better service their clients Fierce competition among communications carriers and hardware and software suppliers Resulted in massive bandwidth increase and plummeting costs Tim Berners-Lee invents HyperText Markup Language (HTML) - Also writes communication protocols to form the backbone new information system = World Wide Web - Hypertext Transfer Protocol (HTTP) a communications protocol used to send information over the web Web use exploded with availability in 1993 of the Mosaic browser Marc Andreessen founds Netscape - Company many credit with initiating the explosive Internet of late 1990s. 7 The Internet A "network of networks" that consists of millions of smaller domestic, academic, business, and government networks. Worldwide, publicly accessible Mixing computing and communications technologies. Carrying information and services, such as electronic mail, online chat, file transfer, and the interlinked Web pages and other documents of the World Wide Web.

5 The World Wide Web Introduced in 1990 by Tim Berners-Lee A system of interlinked, hypertext documents (such as HTML files) accessed via the Internet. With a web browser, a user views web pages that may contain text, images, and other multimedia and navigates between them using hyperlinks. Client-Server Model A web browser (client) lets a user request a resource. A web server takes the client request and gives something back to the client. Clients and servers know HTML. Request Response Client

6 URL & Hyperlinks URL (Uniform/Universal Resource Locator) Web page address typing in Address field - HTTP (HyperText Transfer Protocol) Protocol for transferring data over the Internet - HTTPS (Secure HyperText Transfer Protocol) Protocol for transferring encrypted data over the Internet. Hyperlinks Graphical or textual elements - Click to link to another Web page - Loads new page into browser window World Wide Web Consortium (W3C) 12 W3C Founded in 1994 by Tim Berners-Lee Homepage at Goals Internet universally accessible Standardization - W3C Recommendations: Technologies standardized by W3C include the Extensible HyperText Markup Language (XHTML), Cascading Style Sheets (CSS), HyperText Markup Language (HTML now considered a legacy technology) and the Extensible Markup Language (XML). not an actual software product, but a document that specifies a technology s role, syntax rules and so forth.

7 Web noticeable shift in how people and businesses were using the web and developing web-based applications The term Web 2.0 was coined by Dale Dougherty of O Reilly Web 2.0 definition = companies use the web as a platform to create collaborative, community-based sites (e.g., social networking sites, blogs, wikis, etc.). Web 1.0 (1990s and early 2000s) focused on a small number of companies and advertisers producing content for users to access brochure web ) Web 2.0 involves the Web 1.0 is as a lecture, Web 2.0 is a conversation Websites like MySpace, Facebook, Flickr, YouTube, ebay and Wikipedia, users create the content, companies provide the platforms. Web 2.0 (Cont.) 14 Architecture of participation Open source software Collective Rich Internet Applications (RIAs) Software as a Service (SaaS) Web services incorporate functionality from existing applications and websites into own web applications Amazon Web Services Maps web services with ebay web services

8 Search Content is King Search engines are the primary tools people use to find information on the web Traffic to the major search engines is growing rapidly Americans conducted 8 billion search queries in June 2007, up 26% from the previous year. Attention economy = constant flow of information in today s world causes attention to continually be diverted Search engines have gained popularity by helping users quickly find and filter the information Google Search Google is the leading search and online advertising company founded by Larry Page and Sergey Brin Google s success in search is largely based on its PageRank algorithm and its unique infrastructure of servers Google offers specialty search engines for images, news, videos, blogs and more. Google web services build Google Maps and other Google services into your applications AdWords, Google s pay-per-click (PPC) contextual advertising program AdSense is Google s advertising program for publishers 15 Content Networks 16 Content networks = websites or collections of websites that provide information in various forms articles, wikis, blogs, etc filters the vast amounts of information on the Internet

9 Tagging 17 History of Tagging Tagging, or labeling content, is part of the collaborative nature of Web 2.0 Tag is any user-generated word or phrase that helps organize web content and label it in a more human way] Tag Clouds Visual displays of tags weighted by popularity. Folksonomies Classifications based on tags Formed on sites such as Flickr, Technorati and del.icio.us Flickr Flickr a popular photo-sharing site was launched in February 2004 and acquired by Yahoo! in 2005 Key content-tagging site Technorati Social media search engine that uses tags to find relevant blogs and other forms of social media Software Development 18 Key to Web 2.0 software development KIS (keep it simple; keep it small Important given the attention economy (too much information, too little time) The Webtop Web has now become an application, development, delivery, and execution platform Webtop, or web desktop, allows you to run web applications in a desktop-like environment in a web browser Operating-system independent applications Software as a Service (SaaS) Application software that runs on a web server rather than being installed on the client computer Many benefits - Fewer demands on internal IT departments - Increased accessibility for out-of-the-office use - Easy way to maintain software on a large scale - Examples: Most Google software and Microsoft s Windows Live and Office Live. Collaborating on projects with co-workers across the world is easier Information stored on a web server instead of on a single desktop

10 Software Development 19 Perpetual Beta and Agile Development Shift away from the traditional software release cycle (i.e., new software releases take months or years) Now a greater focus on agile software development, which refers to development of fewer features at a time with more frequent releases - Made possible by using the web as a platform - The Internet is a dynamic medium - Should not overuse betas Open Source Not always free, but the source code is available (under license) to developers, who can customize it to meet their unique needs - Linux operating systems Red Hat or Ubuntu Because the source code is available to everyone, users can look to the community for bug fixes and plug-ins Over 150,000 open source projects are under development - Examples: Firefox web browser, the Apache web server, the MySQL database system, DotNetNuke and PHPNuke Web Services, Mashups, Widgets and Gadgets 20 Incorporating web services into new programs allows people to develop new applications quickly APIs Provide applications with access to external services and databases Examples: Sun s Java API and Web Services APIs Mashups Combine content or functionality from existing web services, websites and RSS feeds to serve a new purpose - Housingmaps.com - Yahoo! Pipes

11 3.16 Web 2.0 Monetization Models 21 Many Web 1.0 businesses discovered that popularity ( eyeballs ) was not the same as financial success Web 2.0 companies are paying more attention to monetizing their traffic Web 2.0 monetization is heavily reliant on advertising Example: Google s AdSense 3.18 Future of the Web 22 Computers have a hard time deciphering meaning from XHTML content Web today involves users interpretations of what pages and images mean, but the future entails a shift from XHTML to a more sophisticated system based on XML, enabling computers to better understand meaning. Web 2.0 companies use data mining to extract as much meaning as they can from XHTML-encoded pages Tagging Early hints a web of meaning. loose classification system Semantic Web Next generation in web development, web of meaning Depends heavily on XML and XML-based technologies Microformats Standard formats for representing information aggregates that can be understood by computers, enabling better search results and new types of applications

12 3.18 Future of the Web (Cont.) 23 Resource Description Framework (RDF) Based on XML Used to describe content in a way that is understood by computers Connects isolated databases across the web with consistent semantics Ontologies Ways of organizing and describing related items, and are used to represent semantics. Another way of cataloging the Internet