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Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Presentation onworld wide web : Presentation onworld wide web What is……. : What is……. Internet : The vast collection of computer networks which form and act as a single huge network for transport of data and messages across distances which can be anywhere from the same office to anywhere in the world World Wide Web: A system of internet server that support Specially formatted documents. The documents are formatted in a markup language called HTML that support link to other documents, as well as graphics audio and video files clicking hot spots How did the internet come to be? : How did the internet come to be? It started as a research project to experiment with connecting computers together with packet switched networks. It was developed with funding and leadership of the Defense Department’s Advanced Research Projects Agency (ARPA). Creation of APRANET : Creation of APRANET 1958 – After USSR launches Sputnik, first artificial earth satellite, US forms the Advanced Research Projects Agency (ARPA), the following year, within the Department of Defense (DoD) to establish US lead in science and technology applicable to the military 1961 – First published work on packet switching (“Information Flow in Large Communication Nets”, Leonard Kleinrock, MIT graduate student)1964 – other independent work in packet switching at RAND Institute and National Physics Laboratory in England From APRANET to Internet : From APRANET to Internet 1972 – ARPANet went ‘public’ ICCC First program for person-to-person communication (e-mail) 1973 75% of all ARPANet traffic is e-mail First international connection (University College of London) 1974 – TCP/IP Each network should work on its own Within each network there would be a ‘gateway’ Packages would be routed through the fastest available route Continue…….. : Continue…….. 1974/1982 – Networks launched Telenet – first commercial version of ARPANet MFENet – researchers into Magnetic Fusion Energy HEPNet – researchers into High Energy Physics SPAN – space physicists Usenet – open system focusing on e-mail and newsgroups Bitnet – university scientists using IBM computers CSNet – Computer Scientists in universities, industry and government Eunet – European version of the Unix network EARN – European version of Bitnet From Internet to www : From Internet to www System expands Advances in computer capacities and speeds Introduction of glass-fibre cables Problems created by its own success More computers are linked (1984 – 1000 hosts) Large volume of traffic (success of e-mail) 1984 – Introduction DNS Use of internet throughout the higher educational system British government – Joint Academic Network US National Science Foundation – NSFNet 1989-1993: internet explosion : 1989-1993: internet explosion 1989 – WWW concept by Tim Berners-Lee 1990 – ARPANET was wound up 1990 – first search-engine (Archie) 1991 – NSF removed restrictions on private access Web browser/Server : Web browser/Server Web Browser: Web Browser is a computer program used for accessing sites or information on a network (as the world wide web). A person utilizes a web browser is to view web pages on internet. : Web Browser: Web Browser is a computer program used for accessing sites or information on a network (as the world wide web). A person utilizes a web browser is to view web pages on internet. Web Server: A Web Server is a computer program that delivers content, such as web pages, using the Hypertext Transfer Protocol over the World Wide Web. Different Types of Web Browser : Different Types of Web Browser Internet Explorer Mozila Firefox Safari Konqueror Opera Web server list : Web server list Apache wer Server-the HTTP Web Server Apache Tomcat Microsoft Windows Server 2003 Inter Information Services(IIS) Lighttpd Jigsaw Klone Sun Java System web Server Zeus Web server Two tier Architecture : Two tier Architecture DATA SERVER: The data based serves up data based on SQL queries submitted by the application. CLIENT SERVER: The application or the client computer consumes the data and presents it in a readable format. The essential components are A Client PC and A Database Server 2-Tier Consideration Client program accesses database directly Client program executes application logic 3-Tier Architecture : 3-Tier Architecture It uses another program at server level. It is called as Server Application. So now client application no longer directly queries to the database, it queries the server Application. Essential components are: i. A Client PC ii. An Application Server iii. A Database Server 3-Tier Considerations Client program contains presentation logic only One server handles many client requests STATE LESS PROTOCOL : STATE LESS PROTOCOL INTRODUCTION : INTRODUCTION A state less protocol is one that does not maintain a relationship between request. Each request is unrelated to any previous request. Example :Hyper Text Transfer Protocol.(HTTP) HYPER TEXT TRANSFER PROTOCOL : HYPER TEXT TRANSFER PROTOCOL HTTP is called stateless protocol as each command is executed independently with out any knowledge of the commands that come before it . It is a protocol used for the web. It is based on request paradigm. HTTP REQUEST METHOD : HTTP REQUEST METHOD Get Method: Method is used to get the data from server. Post Method: The method is used for sending data to the server. Head Method: When a user want to know about the header then this method is used. SIMPLE HTTP COMMUNICATION TRANSACTION : SIMPLE HTTP COMMUNICATION TRANSACTION HTTP AS STATELESS PROTOCOL……..OK? : HTTP AS STATELESS PROTOCOL……..OK? ADVANTAGES This simplifies the server design because it does not need to dynamically allocate storage to deal with conversation in progress or worry about freeing it if a client dies in mid transaction. DISADVANTAGES It may be necessary to include more information in each request and this extra information will need to be interpreted by the server each time. Web page : Web page What is web page? : What is web page? The collection of text, image, sound, and other electronic files stored in World Wide Web format by a user on a Web server for access by others who connect via the World Wide Web. A web page or webpage is a document or resource of information that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a monitor or mobile device. This information is usually in HTML or XHTML format, and may provide navigation to other webpages via hypertext links. Webpages may be retrieved from a local computer or from a remote web server. The web server may restrict access only to a private network, e.g. a corporate intranet, or it may publish pages on the World Wide Web. Webpages are requested and served from web servers using Hypertext Transfer Protocol (HTTP). Static web page : Static web page A static web page (sometimes called a flat page is a web page that is delivered to the user exactly as stored, in contrast to dynamic web pages which are generated by a web application. Consequently a static web page displays the same information for all users, from all contexts, subject to modern capabilities of a web server to negotiate content-type or language of the document where such versions are available and the server is configured to do so. Static web pages are often HTML documents stored as files in the file system and made available by the web server over HTTP. Advantages : Advantages No programming skills are required to create a static page. Inherently publicly cacheable (i.e. a cached copy can be shown to anyone). No particular hosting requirements are necessary. Can be viewed directly by a web browser without needing a web server or application server, for example directly from a CD-ROM or USB Drive. Disadvantages : Disadvantages Any personalization or interactivity has to run client-side (i.e. in the browser), which is restricting. Maintaining large numbers of static pages as files can be impractical without automated tools. Dynamic web page : Dynamic web page A dynamic web page is a hypertext document rendered to a World Wide Web user presenting content that has been customized or actualized for each individual viewing or rendition or that continually updates information as the page is displayed to the user. It is difficult to be precise about "dynamic web page beginnings" or chronology, because the precise concept makes sense only after the "widespread development of web pages": HTTP protocol has been in use since 1990, HTML, as standard, since 1996. The web browsers explosion started with 1993's Mosaic. Two types of dynamic web sites : Two types of dynamic web sites Server-side scripting and content creation way to deal with server-side scripts, at the web servers. Server-side scripting and content creation : Server-side scripting and content creation Server-side scripting and content creation Using server-side scripting to change the supplied page source between pages, adjusting the sequence or reload of the web pages or web content supplied to the browser. Server responses may be determined by such conditions as data in a posted HTML form, parameters in the URL, the type of browser being used, the passage of time, or a database or server state. Server-side dynamic content is more complicated: (1) The client sends the server the request. (2) The server receives the request and processes the server-side script such as [PHP] based on the query string, HTTP POST data, cookies, etc. Web applications : Web applications Introduction : Introduction A web application is an application that is accessed over a network such as Internet or an Intranet. It is a computer software application that is hosted in a browser controlled environment or coded in a browser-supported language and reliant on a common web browser to render the application executable. History : History In 1995, Netscape introduced a client side scripting language called JAVA Script In 1996, Macromedia introduced Flash In 1996, the “web applications” concept was introduced in the JAVA language. In 2005, the term AJAX was coined and applications like G-mail started to make their client sides more and more interactive. Business use: : Business use: An emerging strategy for application software companies is to provide web access to software previously distributed as local applications. Depending on the type of application, it may require the development of an entirely different browser-based interface, or merely adapting an existing application to use different presentation technology. Benefits: : Benefits: Web applications typically require little or no disk space on the client They can be upgraded automatically with new features They integrate easily into other server-side web procedures They also provide cross-platform compatibility in most cases (i.e. Windows, Mac, Linux, etc.) Drawbacks: : Drawbacks: Standard non-compliance is an issue with any now typical office document creator, which creates problems like file sharing and collaboration becomes critical. The applications rely on application files accessed on remote servers though the internet Since many web applications are not open source, there is also a loss of flexibility, not allowing customizations of software, preventing users from running application offline (in many cases) and making user dependent on third-party servers. e-CommerceandNetwork Security : e-CommerceandNetwork Security Introduction : Introduction In the emerging global economy, e-commerce and e-business have increasingly become a necessary component of business strategy and a strong catalyst for economic development. The integration of information and communications technology (ICT) in business has revolutionized relationships within organizations and those between and among organizations and individuals. Specifically, the use of ICT in business has enhanced productivity, encouraged greater customer participation, and enabled mass customization, besides reducing costs. Defining e-Commerce : Defining e-Commerce E-commerce is the use of electronic communications and digital information processing technology in business transactions to create, transform, and redefine relationships for value creation between or among organizations, and between organizations and individuals. Network Security : Network Security What is “Security” : What is “Security” dictionary.com says: 1. Freedom from risk or danger; safety. 2. Freedom from doubt, anxiety, or fear; confidence. 3. Something that gives or assures safety, as: 1. A group or department of private guards: Call building security if a visitor acts suspicious. 2. Measures adopted by a government to prevent espionage, sabotage, or attack. 3. Measures adopted, as by a business or homeowner, to prevent a crime such as burglary or assault: Security was lax at the firm's smaller plant. …etc. Why do we need security? : Why do we need security? Protect vital information while still allowing access to those who need it Trade secrets, medical records, etc. Provide authentication and access control for resources Ex: AFS Guarantee availability of resources Ex: 5 9’s (99.999% reliability) Who is vulnerable? : Who is vulnerable? Financial institutions and banks Internet service providers Pharmaceutical companies Government and defense agencies Contractors to various government agencies Multinational corporations ANYONE ON THE NETWORK Common security attacks and their countermeasures : Common security attacks and their countermeasures Finding a way into the network Firewalls Exploiting software bugs, buffer overflows Intrusion Detection Systems Denial of Service Ingress filtering, IDS TCP hijacking IPSec Packet sniffing Encryption (SSH, SSL, HTTPS) Social problems Education Firewalls : Firewalls Basic problem – many network applications and protocols have security problems that are fixed over time Difficult for users to keep up with changes and keep host secure Solution Administrators limit access to end hosts by using a firewall Firewall is kept up-to-date by administrators Intrusion Detection : Intrusion Detection Used to monitor for “suspicious activity” on a network Can protect against known software exploits, like buffer overflows Denial of Service : Denial of Service Conclusion : Conclusion The Internet (and World Wide Web) was have today was created by some very bright, talented people who either had vision, or were inspired by other talented people’s visions. Though their ideas were not always popular, they pressed ahead. Their perseverance and hard work brought us to where we are today. There is a lot to be learned by studying these people, their early work and keeping in mind what they had to work with. Today, we owe a great deal for the wired world we enjoy, to the hard work of these people. Continued... : Continued... The Internet works only because we implicitly trust one another It is very easy to exploit this trust The same holds true for software It is important to stay on top of the latest CERT security advisories to know how to patch any security holes Thank you : Thank you Presented by : Presented by Vandana Gupta 23/mbm/2009-11 Joyeet Ganguly 35/mbm/2009-11 Ronita Kar 29/mbm/2009-11 Tania Sinha 31/mbm/2009-11 Deep Mukherjee 26/mbm/2009-11 Kanchan Kr Das 20/mbm/2009-11 You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
presentation on www kanchanmbm Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 270 Category: Education License: Some Rights Reserved Like it (0) Dislike it (0) Added: May 11, 2010 This Presentation is Public Favorites: 2 Presentation Description introduction of internet, www, evaluation of www, state less protocol, internet architecture, web browser, e-commerce and network security Comments Posting comment... By: mehak.goyal (15 month(s) ago) pls send me this ppt...i need it urgently... Saving..... Post Reply Close Saving..... Edit Comment Close By: rayenyaas5 (15 month(s) ago) i like this one. . can u send me this powerpoint. . Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Presentation onworld wide web : Presentation onworld wide web What is……. : What is……. Internet : The vast collection of computer networks which form and act as a single huge network for transport of data and messages across distances which can be anywhere from the same office to anywhere in the world World Wide Web: A system of internet server that support Specially formatted documents. The documents are formatted in a markup language called HTML that support link to other documents, as well as graphics audio and video files clicking hot spots How did the internet come to be? : How did the internet come to be? It started as a research project to experiment with connecting computers together with packet switched networks. It was developed with funding and leadership of the Defense Department’s Advanced Research Projects Agency (ARPA). Creation of APRANET : Creation of APRANET 1958 – After USSR launches Sputnik, first artificial earth satellite, US forms the Advanced Research Projects Agency (ARPA), the following year, within the Department of Defense (DoD) to establish US lead in science and technology applicable to the military 1961 – First published work on packet switching (“Information Flow in Large Communication Nets”, Leonard Kleinrock, MIT graduate student)1964 – other independent work in packet switching at RAND Institute and National Physics Laboratory in England From APRANET to Internet : From APRANET to Internet 1972 – ARPANet went ‘public’ ICCC First program for person-to-person communication (e-mail) 1973 75% of all ARPANet traffic is e-mail First international connection (University College of London) 1974 – TCP/IP Each network should work on its own Within each network there would be a ‘gateway’ Packages would be routed through the fastest available route Continue…….. : Continue…….. 1974/1982 – Networks launched Telenet – first commercial version of ARPANet MFENet – researchers into Magnetic Fusion Energy HEPNet – researchers into High Energy Physics SPAN – space physicists Usenet – open system focusing on e-mail and newsgroups Bitnet – university scientists using IBM computers CSNet – Computer Scientists in universities, industry and government Eunet – European version of the Unix network EARN – European version of Bitnet From Internet to www : From Internet to www System expands Advances in computer capacities and speeds Introduction of glass-fibre cables Problems created by its own success More computers are linked (1984 – 1000 hosts) Large volume of traffic (success of e-mail) 1984 – Introduction DNS Use of internet throughout the higher educational system British government – Joint Academic Network US National Science Foundation – NSFNet 1989-1993: internet explosion : 1989-1993: internet explosion 1989 – WWW concept by Tim Berners-Lee 1990 – ARPANET was wound up 1990 – first search-engine (Archie) 1991 – NSF removed restrictions on private access Web browser/Server : Web browser/Server Web Browser: Web Browser is a computer program used for accessing sites or information on a network (as the world wide web). A person utilizes a web browser is to view web pages on internet. : Web Browser: Web Browser is a computer program used for accessing sites or information on a network (as the world wide web). A person utilizes a web browser is to view web pages on internet. Web Server: A Web Server is a computer program that delivers content, such as web pages, using the Hypertext Transfer Protocol over the World Wide Web. Different Types of Web Browser : Different Types of Web Browser Internet Explorer Mozila Firefox Safari Konqueror Opera Web server list : Web server list Apache wer Server-the HTTP Web Server Apache Tomcat Microsoft Windows Server 2003 Inter Information Services(IIS) Lighttpd Jigsaw Klone Sun Java System web Server Zeus Web server Two tier Architecture : Two tier Architecture DATA SERVER: The data based serves up data based on SQL queries submitted by the application. CLIENT SERVER: The application or the client computer consumes the data and presents it in a readable format. The essential components are A Client PC and A Database Server 2-Tier Consideration Client program accesses database directly Client program executes application logic 3-Tier Architecture : 3-Tier Architecture It uses another program at server level. It is called as Server Application. So now client application no longer directly queries to the database, it queries the server Application. Essential components are: i. A Client PC ii. An Application Server iii. A Database Server 3-Tier Considerations Client program contains presentation logic only One server handles many client requests STATE LESS PROTOCOL : STATE LESS PROTOCOL INTRODUCTION : INTRODUCTION A state less protocol is one that does not maintain a relationship between request. Each request is unrelated to any previous request. Example :Hyper Text Transfer Protocol.(HTTP) HYPER TEXT TRANSFER PROTOCOL : HYPER TEXT TRANSFER PROTOCOL HTTP is called stateless protocol as each command is executed independently with out any knowledge of the commands that come before it . It is a protocol used for the web. It is based on request paradigm. HTTP REQUEST METHOD : HTTP REQUEST METHOD Get Method: Method is used to get the data from server. Post Method: The method is used for sending data to the server. Head Method: When a user want to know about the header then this method is used. SIMPLE HTTP COMMUNICATION TRANSACTION : SIMPLE HTTP COMMUNICATION TRANSACTION HTTP AS STATELESS PROTOCOL……..OK? : HTTP AS STATELESS PROTOCOL……..OK? ADVANTAGES This simplifies the server design because it does not need to dynamically allocate storage to deal with conversation in progress or worry about freeing it if a client dies in mid transaction. DISADVANTAGES It may be necessary to include more information in each request and this extra information will need to be interpreted by the server each time. Web page : Web page What is web page? : What is web page? The collection of text, image, sound, and other electronic files stored in World Wide Web format by a user on a Web server for access by others who connect via the World Wide Web. A web page or webpage is a document or resource of information that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a monitor or mobile device. This information is usually in HTML or XHTML format, and may provide navigation to other webpages via hypertext links. Webpages may be retrieved from a local computer or from a remote web server. The web server may restrict access only to a private network, e.g. a corporate intranet, or it may publish pages on the World Wide Web. Webpages are requested and served from web servers using Hypertext Transfer Protocol (HTTP). Static web page : Static web page A static web page (sometimes called a flat page is a web page that is delivered to the user exactly as stored, in contrast to dynamic web pages which are generated by a web application. Consequently a static web page displays the same information for all users, from all contexts, subject to modern capabilities of a web server to negotiate content-type or language of the document where such versions are available and the server is configured to do so. Static web pages are often HTML documents stored as files in the file system and made available by the web server over HTTP. Advantages : Advantages No programming skills are required to create a static page. Inherently publicly cacheable (i.e. a cached copy can be shown to anyone). No particular hosting requirements are necessary. Can be viewed directly by a web browser without needing a web server or application server, for example directly from a CD-ROM or USB Drive. Disadvantages : Disadvantages Any personalization or interactivity has to run client-side (i.e. in the browser), which is restricting. Maintaining large numbers of static pages as files can be impractical without automated tools. Dynamic web page : Dynamic web page A dynamic web page is a hypertext document rendered to a World Wide Web user presenting content that has been customized or actualized for each individual viewing or rendition or that continually updates information as the page is displayed to the user. It is difficult to be precise about "dynamic web page beginnings" or chronology, because the precise concept makes sense only after the "widespread development of web pages": HTTP protocol has been in use since 1990, HTML, as standard, since 1996. The web browsers explosion started with 1993's Mosaic. Two types of dynamic web sites : Two types of dynamic web sites Server-side scripting and content creation way to deal with server-side scripts, at the web servers. Server-side scripting and content creation : Server-side scripting and content creation Server-side scripting and content creation Using server-side scripting to change the supplied page source between pages, adjusting the sequence or reload of the web pages or web content supplied to the browser. Server responses may be determined by such conditions as data in a posted HTML form, parameters in the URL, the type of browser being used, the passage of time, or a database or server state. Server-side dynamic content is more complicated: (1) The client sends the server the request. (2) The server receives the request and processes the server-side script such as [PHP] based on the query string, HTTP POST data, cookies, etc. Web applications : Web applications Introduction : Introduction A web application is an application that is accessed over a network such as Internet or an Intranet. It is a computer software application that is hosted in a browser controlled environment or coded in a browser-supported language and reliant on a common web browser to render the application executable. History : History In 1995, Netscape introduced a client side scripting language called JAVA Script In 1996, Macromedia introduced Flash In 1996, the “web applications” concept was introduced in the JAVA language. In 2005, the term AJAX was coined and applications like G-mail started to make their client sides more and more interactive. Business use: : Business use: An emerging strategy for application software companies is to provide web access to software previously distributed as local applications. Depending on the type of application, it may require the development of an entirely different browser-based interface, or merely adapting an existing application to use different presentation technology. Benefits: : Benefits: Web applications typically require little or no disk space on the client They can be upgraded automatically with new features They integrate easily into other server-side web procedures They also provide cross-platform compatibility in most cases (i.e. Windows, Mac, Linux, etc.) Drawbacks: : Drawbacks: Standard non-compliance is an issue with any now typical office document creator, which creates problems like file sharing and collaboration becomes critical. The applications rely on application files accessed on remote servers though the internet Since many web applications are not open source, there is also a loss of flexibility, not allowing customizations of software, preventing users from running application offline (in many cases) and making user dependent on third-party servers. e-CommerceandNetwork Security : e-CommerceandNetwork Security Introduction : Introduction In the emerging global economy, e-commerce and e-business have increasingly become a necessary component of business strategy and a strong catalyst for economic development. The integration of information and communications technology (ICT) in business has revolutionized relationships within organizations and those between and among organizations and individuals. Specifically, the use of ICT in business has enhanced productivity, encouraged greater customer participation, and enabled mass customization, besides reducing costs. Defining e-Commerce : Defining e-Commerce E-commerce is the use of electronic communications and digital information processing technology in business transactions to create, transform, and redefine relationships for value creation between or among organizations, and between organizations and individuals. Network Security : Network Security What is “Security” : What is “Security” dictionary.com says: 1. Freedom from risk or danger; safety. 2. Freedom from doubt, anxiety, or fear; confidence. 3. Something that gives or assures safety, as: 1. A group or department of private guards: Call building security if a visitor acts suspicious. 2. Measures adopted by a government to prevent espionage, sabotage, or attack. 3. Measures adopted, as by a business or homeowner, to prevent a crime such as burglary or assault: Security was lax at the firm's smaller plant. …etc. Why do we need security? : Why do we need security? Protect vital information while still allowing access to those who need it Trade secrets, medical records, etc. Provide authentication and access control for resources Ex: AFS Guarantee availability of resources Ex: 5 9’s (99.999% reliability) Who is vulnerable? : Who is vulnerable? Financial institutions and banks Internet service providers Pharmaceutical companies Government and defense agencies Contractors to various government agencies Multinational corporations ANYONE ON THE NETWORK Common security attacks and their countermeasures : Common security attacks and their countermeasures Finding a way into the network Firewalls Exploiting software bugs, buffer overflows Intrusion Detection Systems Denial of Service Ingress filtering, IDS TCP hijacking IPSec Packet sniffing Encryption (SSH, SSL, HTTPS) Social problems Education Firewalls : Firewalls Basic problem – many network applications and protocols have security problems that are fixed over time Difficult for users to keep up with changes and keep host secure Solution Administrators limit access to end hosts by using a firewall Firewall is kept up-to-date by administrators Intrusion Detection : Intrusion Detection Used to monitor for “suspicious activity” on a network Can protect against known software exploits, like buffer overflows Denial of Service : Denial of Service Conclusion : Conclusion The Internet (and World Wide Web) was have today was created by some very bright, talented people who either had vision, or were inspired by other talented people’s visions. Though their ideas were not always popular, they pressed ahead. Their perseverance and hard work brought us to where we are today. There is a lot to be learned by studying these people, their early work and keeping in mind what they had to work with. Today, we owe a great deal for the wired world we enjoy, to the hard work of these people. Continued... : Continued... The Internet works only because we implicitly trust one another It is very easy to exploit this trust The same holds true for software It is important to stay on top of the latest CERT security advisories to know how to patch any security holes Thank you : Thank you Presented by : Presented by Vandana Gupta 23/mbm/2009-11 Joyeet Ganguly 35/mbm/2009-11 Ronita Kar 29/mbm/2009-11 Tania Sinha 31/mbm/2009-11 Deep Mukherjee 26/mbm/2009-11 Kanchan Kr Das 20/mbm/2009-11