1 web technologies
- 1. Introduction
- 2. What is Web? The Web, or World Wide Web (W3), is basically a system of Internet servers that support specially formatted documents. The Web is the common name for the World Wide Web, a subset of the Internet consisting of the pages that can be accessed by a Web browser. Some people assume that Web is the same as the Internet, and use these terms interchangeably.
- 3. Internet and WWW Inter-network and World Wide Web Interlinked hypertext documents accessed using HTTP Protocol Client - Server architecture
- 4. Some historical details Start of standard groups TCP handles conversion between messages and streams packets IP handles addressing of packets across networks TCP/IP enables packets to be sent across multiple networks using multiple standards Telnet One of the earliest standards for exchanging transmission, directly connect accounts on different systems. SMTP specifies another way of direct connection
- 5. Some historical details MIME Extension to the SMTP Protocol which supports the exchange of richer data files such as audio-, video-, and images data. FTP (1973) supports file transfer between Internet sites and allows a system to publish a set of files by hosting an FTP sever innovation permits anonymous users to transfer files Archie Late 1980‘s distributed file system based on FTP Gopher First simple system, providing GUI
- 6. Why Internet? Use of internet Email Social Networking, Chat Information sharing Getting updates – News around the world Entertainment – Games, Videos and Music Virtual classrooms Remote Access Online Jobs
- 7. Why Websites? Offline Apps vs. Online Apps ONLINE APPS No need to install Just login and use Available from anywhere where Internet connection is available Operating system independent No piracy issues OFFLINE APPS Ease of use Generally have more features Easier to develop but difficult to update
- 8. Technologies Overview List of Technologies Client Side Technologies HTML, CSS, JavaScript, VBScript XHTML, DHTML, WML, AJAX FLASH Server Side Technologies ASP, PHP, Perl, JSP ASP.NET, Java MySQL, SQL Server, Access
- 9. Technologies Overview List of Technologies Some More Advanced Technologies XML, XSLT, RSS, Atom X-Path, XQuery, WSDL XML-DOM, RDF Ruby on Rails, GRAIL Framework REST, SOAP ExpressJS, NodeJS, React NativeJS, AngularJS
- 10. How to choose a Technology? Depends on: What is the type of content? Who is your audience? Who will modify your content? What are your Future Plans? Availability of technology? Your previous experience? Portability and Data sharing
- 11. Core Web Technologies HTTP(HyperText Transfer Protocol) generic, stateless protocol governs the transfer of files across a network developed at CERN (Central European Research Network), they also came up with the name WWW, later W3C supports access to SMTP,FTP and other protocols was designed to support hypertext
- 12. Core Web Technologies Exchanged information, can be static or dynamic Every resource, accessible over the Web has a URL(Uniform resource locator) HTTP mechanism is based on client/server model typically using TCP/IP sockets
- 13. Core Web Technologies since Version 1.1 HTTP requires servers to support persistent connections, to minimize overhead associated with opening and closing connections. Typical methods on the server side are: OPTIONS send information about the communication options GET retrieve document or document produced by a program POST Append or attach information PUT Store information DELETE Delete the resource indicated in the request
- 14. Core Web Technologies Another limitation HTTP is stateless Does not provide storing of information between requests No indication of any relationship between two different requests cookies, small data structures that a web server requests the HTTP client to store on the local machine, are used to maintain state information e.g. cookies store recently view items on a web shop
- 15. Some Web Terms Web Standards Web Browser Web Services Web Server Web Page Web Hosting Web Storage Web Stack Web Site Web Application Web Portal
- 16. Web Engineering Web Engineering is the application of systematic, disciplined and quantifiable approaches to development, operation, and maintenance of Web-based applications. It is both a pro-active approach and a growing collection of theoretical and empirical research in Web application development.