Web Technology(NCS-504)

Prepared ByMr. Abhishek Kesharwani

Assistant Professor,UCER Naini,Allahabad

Introduction and Web Development Strategies

World Wide Web: The World Wide Web is a system of interlinked hypertext documents

accessed via the Internet. Web is a huge collection of pages of information linked to each other around the globe.

History of WWW:• WWW is created by Sir Tim Berners Lee in 1989 at CERN in

Geneva.• In 1990, the first text only browsers were setup and CERN

scientist could access hypertext files and other information at CERN. HTML was based on a subset of the standard generalized markup language (SGML). To transfer HTML document to remote sites a new protocol was devised called HTTP (Hyper Text Transfer Protocol).

• In the fall of 1991, conference goes around the world started hearing about the promise but sparks still were not flying.

• In 1993, there are only about 50 websites world wide. A browser that allowed user to take advantage of the web’s graphical capabilities was developed at the National center for Super Computing application (NCSA). NCSA called the browser Mosaic.

Protocols Governing WebProtocol: A protocol is a set of rules that is used to communicate

applications to each other. OR A protocol is the interface required for communicating the different

applications.Classification: a. HTTP b. TCP/IP c. FTPd. SMTP e. TELNET

HTTP

HTTP: HTTP is the primary protocol used to distribute information on the web.

Initial HTTP 0.9 does not allow for content typing and does not have provisions for supplying meta-information.

Content Typing: To identify the type of data being transferred.

Meta Information: It is supplemental data, such as environment variables that identify the client’s computer

• TCP/IP: It is a set of rules that an application can use to package its information for sending across the networks of networks.

• FTP: It is used to transfer the files over networks.

FTP uses TCP to create a virtual connection for control information and then creates a separate TCP connection for data transfers. The control connection uses an image of the TELNET protocol to exchange commands and messages between hosts.

• Simple Mail Transfer Protocol (SMTP) is an Internet standard for electronic mail (e-mail) transmission across Internet Protocol (IP) networks.

• Telnet: Telnet lets you remotely log into another system and browse files and directories on that remote system.

Comparison between traditional project and web project:

Web Projects 1. Project managers are not client.2. Often beta technologies are used for testing, often without tech support.3. Pricing model for web projects does not exist.4. Team roles are less specialized. 5. Clients are often unwilling to bear the cost of web development.6. Standards for web projects do not exist. 7. Project manager’s responsibilities are very broad.

Traditional Projects 1. They are always different. 2. It is not applicable in this case 3. It do exist for traditional projects. 4. More specialized. 5. Difficult of traditional projects. 6. Standards for traditional projects exist. 7. Not true for these projects.

Web Development Strategies

1. Strategy: · Goals and objectives · Team building · Research and review · Project proposal

2. Design and Specification: · Developing concept · Content planning · Rough design · Final design 3. Produced desired Result: · Build prototype · Prototype testing · Original design · Satisfy the clients need

4. Testing and maintenance: · Test the code · Maintain the web server. 5. Register with ISP: · Register domain name · Get web space 6. Launch: · Connect domain name with web server· Finally host the web accordingly.

Connecting to Internet

• All modern computers and laptops are capable of connecting to the internet, as are many other devices, including mobiles, tablets, e-readers, televisions, video games consoles.

• There are two ways of getting the internet at home. The most popular way is to have your telephone line (also known as a ‘landline’) converted to broadband so that it can carry normal phone calls and internet data at the same time.

• if you don’t have a landline or if you want to be able to use the internet when you’re out and about, you might prefer mobile internet from one of the mobile network providers. This can be used anywhere there’s a mobile signal but does tend to be slower and more expensive than broadband through a landline.

Step-by-Step instructions to connect to the internet

• Step 1: Choose an internet service provider (ISP). This could be the company that provides your telephone line or it could be one of the many independent providers.

• Step 2: Having chosen an ISP and signed the contract, you’ll have to wait a few days while your line is converted to broadband. During this time, you should receive a letter with your username and password and the hardware you’ll need: a small box called a 'router' and its attachments.

Step 3: Once you’re told that your broadband is active, you can set up your router. It should have come with three cables:

• a network cable to connect the router to your computer• a power cable• a cable that will go between your router and a micro filter• Plug one end of the network cable into the appropriately

shaped socket in the router, and the other end in a similarly appropriately shaped socket in your computer.

• Step 4: When you get the router, you should also receive a CD. Once you’ve set up the router, all you need to do is put the CD into your computer and follow the step-by-step instructions. Create the broadband connection.

Types of Internet Services

• World Wide Web • Telnet • Electronic Mail • FTP - File Transfer Protocol • Chat • Email• Newsgroups

Client-Server Computing

Client-Server Computing

• Client/server computing is a software engineering technique often used within distributed computing that allows two independent processes to exchange information, through a dedicated connection.

• Client/Server computing is NOT having one computer set up as a server and having another computer set up as a client.

• Client and server software components also can communicate with each other when they are installed on the same computer.

• Most client/server software components are set up to communicate with a peer process over a virtual, direct channel.

• Client/Server computing is NOT concerned directly with communications over the network. That is, C/S is not interested in the intricacies of how one machine communicates with another, or with how the bits are pushed through the coax. The very same network components may be used by both client and server software components.

The client's responsibility is usually to:

1. Handle the user interface. 2. Translate the user's request into the desired

protocol. 3. Send the request to the server. 4. Wait for the server's response. 5. Translate the response into "human-readable"

results. 6. Present the results to the user.

The server's functions include: 1. Listen for a client's query. 2. Process that query. 3. Return the results back to the client.

Client/Server interaction goes like this:

• The user runs client software to create a query. • The client connects to the server. • The client sends the query to the server. • The server analyzes the query. • The server computes the results of the query. • The server sends the results to the client. • The client presents the results to the user. • Repeat as necessary.