What is the difference between HTTP and HTTPS?

HTTP is quite a common language with us and stands for hyper text transfer protocol. This is actually an application protocol that has been developed exclusively for the hyper media, collaborative and distributed information systems. 

The foundation of the data communication is entirely based upon www or World Wide Web.  

Now what is HTTPS? HTTPS is nothing but HTTP secure! This one is much more secure than usual hyper text transfer protocol. And like HTTP, it is also a quite popular communication protocol for a much secure communication over a network of computers. It is quite popular with internet. 

If you see it technically, it is actually not a protocol in itself but rather a layered form of HTTP along with SSL/ TLS protocol. This allows the security capabilities of the SSL/ TLS to be added to the HTTP.  In this article we hold up to discuss the differences between the two i.e., the HTTP and HTTPS.

Difference #1:

- The transmission and receiving of the information across a computer network or internet is solely the responsibility of the HTTP.   

- HTTPS holds the responsibility of exchanging confidential information among the servers and also since the access to such information has to be secured to prevent it from any un- authorized access.

Difference #2:

-The transmission of HTTP takes place through a wire via PORT 80(TCP) but it is not at all secure! Some can easily interfere in the communication between your system and the server. 

- HTTPS is a creation of the NetScape and it comes as a built in thing with the netscape browser that uses it for the encryption and decryption of the user’s requests.

- HTTPS is actually HTTP working over the layer of netscape’s secure socket layer (SSL). 

- Unlike regular HTTP, HTTPS transmission takes place through a wire via PORT 443 for carrying out interactions between the lower layer TCP/ IP. 

- SSL or secure socket layer makes use of a 40 bit key size for encrypting the RC4 streams algorithm. 

- Therefore an adequate degree of encryption is possible for commercial exchange.

Difference #3:

- HTTPS being so very secure finds its use in shopping/ commercial sites and login pages. 

- HTTPS though being a standard secure protocol transmits the data over world wide web just like HTTP with the only difference being in the form in which data is transmitted i.e., the encrypted form. 

- When you put https:// instead of http:// you are asking the server to establish a secure connection path. 

- The server makes it a point that the secure and non secure connections are kept separately. 

- When the address in the address bar of the web browser that you are using, starts with http://, it simply means that your requests are being communicated over regular un-secure “HTTP” language.

- It is basically the letter ‘S’ that makes all the difference between HTTP and HTTPS. 

Difference #4:

- Most of the requests of the clients are processed via HTTP. The client in turn gets a response from the server on the completion of a request in the form of a web page. 

- In HTTPS the information is highly encrypted which means that no can have a clue of what you are looking for. 

This type of secure communication is commonly prevalent in those areas wheer security is quite mandatory like the following:

1. E- mails
2. Banking web sites
3. Payment gateways and so on.

To get an HTTPS connection, the server requires a public key trusted and signed certificate.

What are Web engineering Systems? What are the attributes for web based systems?

Web systems deliver complex array of content and functionality to end users. Web engineering creates high quality web applications. Web based systems grow complex, a failure in one can propagate broad based problems. There is a need for disciplined approaches and new methods and tools for development, deployment and evaluation of web based systems and applications.

Attributes for web based systems are:
- A web application should serve the needs of different community of clients.
- A large number of users may access the web application at one time.
- Web application should be able to handle unpredictable load.
- Users of popular web application demand access and availability of them round the clock.
- Web applications uses hypermedia and access information that exists on databases that were originally not a part of web based environment.
- The content should be of good quality.
- Web applications evolve continuously. Continuous care and feeding allows a web site to grow.
- Web applications exhibit a time to market. Web engineers use methods for planning, analysis, design, implementation and testing to compress time schedules.
- To protect sensitive content and provide secure modes of data transmission, strong security measures should be implemented.
- The look and feel of a web application should be appealing.

The categories of web applications that are encountered in web engineering are informational, download, customization, interaction, user input, transaction oriented, service oriented, portal, database access, data warehousing.

Object Oriented Hypermedia Design Method (OOHDM)

Object Oriented Hypermedia Design Method (OOHDM) is a method for designing web applications. The development of hypermedia applications consists of four different design activities :

- Conceptual Design for OOHDM
In conceptual design, a conceptual schema is built that represents objects, relationships and collaborations existing in the target domain. To create class diagrams, aggregations and class representations, diagrams and other information, Unified Modelling Language(UML) is used.

- Navigational Design for OOHDM
In OOHDM, the navigational design is build over the view of conceptual design. It uses a predefined set of navigation classes like nodes, links, anchors and structures. Navigation design is expressed in two schema's, the Navigational Class schema and the Navigational Context schema.
Objects that are derived from classes defined in conceptual design are called navigational objects. A series of navigational classes or nodes are defined to encapsulate these objects.
Navigational design must take into account the way in which the user explores the hypermedia space.

-Abstract Interface Design
Abstract Interface Design specifies the interface objects. To represent the relationship between interface and navigation objects, a formal model of interface objects called Abstract Data View is used. The abstract data view defines:
- a static layout.
- behavioral component.

- Implementation
Any application-specific model, like OOHDM design, must be eventually implemented using an implementation technology. This activity represents a design iteration that is specific to the environment in which web application will operate.

Hypermedia Design Patterns in Web Engineering

Web engineering uses design patterns. These are of two types:
- Generic design patterns - applicable for every software.
- Hypermedia design pattern - specific to WebApps.
Design problems can be solved by using design patterns. There are some pattern categories:

NAVIGATION PATTERNS
These patterns helps in the design of NSU, navigation links and overall navigation flow of the web application.

ARCHITECTURAL PATTERNS
It helps in the design of content and web application architecture. Many architectural patterns are available for web engineers who design web applications in various business domains.

COMPONENT CONSTRUCTION PATTERNS
The web application components can be combined by the methods provided by these patterns. When data processing functionality is required within a web application, the architectural and component level design patterns are applicable.

PRESENTATION PATTERNS
Presentation patterns assist in the presentation of content as it is presented to the user via the interface. They tell how to organize user interface control functions, shows the relationship between an interface action and the content object it affects, establish content hierarchies.

BEHAVIOR AND USER INTERACTION PATTERNS
These patterns assist in design of user machine interaction. They address how the interface informs the user of the consequences of a specific action, how a user expands content based on usage context, how to best describe the destination that is implied by a link.

Introduction: WWW - The Client Side

The Internet / World Wide Web consists of pages and each page contains links or pointers to other pages. Users follow the link by clicking on them. This process can be repeated indefinitely, possibly traversing hundreds of linked pages. Pages that point to other pages are said to use "hypertext".

Pages are viewed with a program called a browser. When a page is requested, the browser fetches, interprets the text and formats the commands that it contains and displays the page. Strings of text that are links to other pages are called hyperlinks.

Most browsers have numerous buttons and features to navigate the Web. In addition to having ordinary text and hypertext, web pages also contain icons, line drawings, maps and photographs. Some pages also consist of audio tracks, video clips, or both. When hypertext pages are combined with other media, the result is called hypermedia. Many Web pages consists of large images which take a long time to load.

Some browsers deal with slow loading of images by first fetching and displaying the text, then getting the images. Some Web pages contain forms that request the user to enter information. Some browsers use the local disk to cache pages that they have fetched. A check is made before a page is fetched to see if it is in the local cache. If so, check if it is up to date. If so,there is no need to load the page again.

To host a web browser, a machine must be directly connected to Internet or have a SLIP or PPP connection to a router or other machine that is directly on Internet.