Web-Server & It's Architecture.pptx
- 1. Alok Kumar, Damewanshwa Ryntathiang, Rituraj Borah, Iakitbok Nongrum S2000940 S2000945 S2000957 S2000947
- 2. ++ CONTENTS
- 3. Tim Berners-Lee wrote the first proposal for the World Wide Web in March 1989 and his second proposal in May 1990. Together with Belgian systems engineer Robert Cailliau, this was formalised as a management proposal in November 1990. This outlined the principal concepts and it defined important terms behind the Web. The document described a "hypertext project" called "WorldWideWeb" in which a "web" of "hypertext documents" could be viewed by “browsers”.By the end of 1990, Tim Berners-Lee had the first Web server and browser up and running at CERN, demonstrating his ideas. He developed the code for his Web server on a NeXT computer. To prevent it being accidentally switched off, the computer had a hand-written label in red ink: "This machine is a server. DO NOT POWER IT DOWN!!"
- 4. The main job of a web server is to display website content through storing, processing and delivering webpages to users. A web server is software and hardware that uses HTTP (Hypertext Transfer Protocol) and other protocols to respond to client requests made over the World Wide Web. Every Web server that is connected to the Internet is given a unique address made up of a series of four numbers between 0 to 255 separated by periods. For example, 68.178.157.132 or 68.122.35.127.
- 6. Request a file from web document (*html, *.gif, etc.) Find existing thread/process corresponding to the user's connection, or start new one. Parse HTTP request, extracting file name and path of requested file. Find and retrieve requested file, or return error message. Parse response and display in web browser.Repeat until all files in web document have been retrieved. Add HTTP header and send response to user.
- 7. A B C Getting IP Address from DNS: In the First step, web browser gets the IP (Internet Protocol) from domain name. IP address can be received with two methods like as Finding IP address in Cache and requesting IP address in multiple DNS (Domain Name Servers). Browser Request Fully URL: Web browser fully aware which IP address website is located at, so it can send request full URL from server side. Web Server sends Requested Page: Now web server responds with sending requested web page toward web browser. If those web pages do not present then appropriate error message will be display on the web browser. For example – “Error 404 will be display, if your requested pages do not present”.” Error 401 will be display, if user inserts incorrect credential information such as username and password.”
- 8. The document root is the root directory of servable documents Suppose the site name is www.bloomers.com and the document root is named topdocs, and it is stored in the /admin/web directory Then, /admin/web/topdocs is the document directory address If a request URL is http://www.bloomers.com/bulbs/tulips.html The server will search for the file named /admin/web/topdocs/bulbs/tulips.html The server can have virtual document trees Sometimes a different disk, possibly on a different machine, is used after the original disk is filled
- 9. The server root usually has four files/subdirectories 1) One is the code for the server itself 2) conf - subdirectory for configuration information 3) logs - subdirectory to store what has happened 4) cgi-bin - subdirectory for executable scripts
- 10. Virtual hosts - multiple sites on the same system Proxy servers - to serve documents from the document roots of other sites Besides HTTP, support for FTP, Gopher, News, email Support for database access
- 11. A client-server architecture or model is an application network separating tasks between the clients and servers that live in the same system or have to communicate through a computer network. The server-client mainly relies on sending the request to another program to access the service made accessible by the server. This server runs a few programs that share the resources with & distribute work among the clients.It is also known as the networking computing model or client server network as all requests and services are delivered over a network. A client-server relationship corresponds to the request–response pattern and should adhere to the common communications procedure that defines the language, rules, or dialog patterns used. The client-server communication adheres to TCP or IP protocol suite.
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- 13. A 1-Tier Architecture: All client or server configuration settings, UI environment, data logic, as well as marketing logic are there on the same system. The 1-tier architecture services are quite reliable but tough tasks to handle as they have all data in various variance that will be allotted the complete replication of the whole work. 1-Tier architecture also has different layers. For example –Business, Presentation, Data Access layer using a single software package. Data will be saved on a local machine. Some applications manage 3 tiers like an MP3 player and MS Office; however, these applications are presented in a 1-tier architecture system.
- 14. B 2-Tier Architecture: In 2-Tier Architecture, the UI is stored at the client machine, and the database gets stored on a server. The business logic and database logic are filed at server or client but have to be well-maintained. Suppose Data Logic and Business Logic are collected at the client-side, it’s called fat client-server architecture. Suppose Data Logic and Business Logic are handled on a server, its thin client-server architecture. It is considered affordable. In 2-Tier architecture, server and client need to come in the direct incorporation. Suppose a client provides any input to a server there must not be any intermediate. It is generally done for rapid results and to avoid confusion between various clients. For example, an online ticket reservations application uses this 2-Tier architecture. USER INTERFACE either with BL & DL DATABASE or BL & DL Reques t Response CLIENT SERVE R
- 15. C 3-Tier Architecture: It consists of the presentation tier that is the User Interface layer, an application tier that is a service layer, which performs the detailed processing, and a data tier that consists of the database server, which stores information. Three-tier architecture can be split into 3 parts, the presentation layer (or Client Tier), the Application layer (or Business Tier), and the Database layer (or Data Tier). It works in the following ways: The Client system handles the Presentation layer; the Application server looks after the Application layer, and the Server system supervises the Database layer. USER INTERFACE CLIENT SERVE R MIDDLEWAR E BL & DL DATABAS E Request Response
- 16. • Client and server machines need different amount of hardware and software resources. • Client and server machines may belong to different vendors. • A client or server application interacts directly with a transport layer protocol to establish communication and to send or receive information. • The transport protocol then uses lower layer protocols to send or receive individual messages. Thus, a computer needs a complete stack of protocols to run either a client or a server. • A single server-class computer can offer multiple services at the same time; a separate server program is needed for each service.
- 17. A Advantages: • Cost-efficient needs less maintenance cost & Data recovery is made possible. • The capacity of the Client/Servers will be changed separately. • Centralized system with data in one single place. B Disadvantages: • Clients can be prone to viruses, worms, and Trojans if present in a Server/uploaded in the Server. • The server can be prone to Denial of Service attacks. • Data packets will be modified or spoofed during the transmission. • Phishing and capturing login credentials and other useful info of user are quite common and Man in a Middle attack will be common.
- 18. A Mail Servers: Email servers can be used for sending & receiving emails. Different software allows email handling. B File Servers: They are the centralized location for the files. For example, cloud services for Microsoft Office and Google docs will be accessed from your devices, and files that you save from the computer will be accessed from your phone. In this way, file stores will be centralized and accessed by multiple clients.
- 19. EXPLAIN THE CLIENT-SIDE OF WWW ARCHITECTURE. Processing taking place on the users computer: • On client-side it generally refers to the device through which the user is accessing the internet. • A browser is needed to execute the scripts on the machine i.e. any file with an extension like .js or .html requires a browser to run. • Reduces load on the server processing unit. For example, CDNs are distributed networks comprised of strategically placed edge servers that enable the rapid delivery of web content to users across the world. • A CDN can reduce your server load and speed up your website by caching your site's static content.
- 20. • Web server is a program or the computer that provide services to other programs called client. • The Web server accepts, approve and respond to the request made by the web browser for a web document or services. • The web server gets HTTP requests and send HTTP responses. Web Server Web Browser • There exist three types of processing models for web server i.e Process-based, Thread based and Hybrid. • Web servers provide an area to store and organize the pages of the website. • Example: Apache, Nginx, IIS etc. • Web Browser is an Application program that displays a World wide web document. It usually uses the internet service to access the document. • The Web browser requests the server for the web documents and services. • The web browser sends an HTTP request and gets an HTTP response. • Doesn’t exist any processing model for the web browser. • Web browser stores the cookies for different websites. • Example: Crome, Brave, MS Edge etc.
- 21. • https://www.techtarget.com/whatis/definition/Web-server • https://eduladder.com/viewquestions/975/Explain-Web-servers- operation-and- general-server-characteristics • https://www.tutorialspoint.com/internet_technologies/web_servers.htm • https://intellipaat.com/blog/what-is-client-server- architecture/#:~:text=Client%20server%20architecture%20is%20a,are%20deliver ed%20over%20a%20network. • http://web.cs.wpi.edu/~kal/courses/awt/lab6/wwwch11servlets.PDF • https://digitalthinkerhelp.com/what-is-web-server-definition-types-examples- working-uses/ • https://www.postposmo.com/en/characteristics-of-a-web- server/#Caracteristicas_de_un_servidor_web_Software • https://cs.uwaterloo.ca/~m2nagapp/courses/CS446/1195/Arch_Design_Activity/C lientServer.pdf • https://www.thecrazyprogrammer.com/2021/03/client-server-architecture.html • https://www.ques10.com/p/10217/explain-the-need-of-web-server-how-is-it- adminis-2/ • https://www.geeksforgeeks.org/difference-between-web-browser-and-web- server/
Editor's Notes
- #5: A web server is computer software and underlying hardware that accepts requests via HTTP (the network protocol created to distribute web content) or its secure variant HTTPS. A user agent, commonly a web browser or web crawler, initiates communication by making a request for a web page or other resource using HTTP, and the server responds with the content of that resource or an error message. A web server can also accept and store resources sent from the user agent if configured to do so.