When an address is typed into a browser, the browser establishes a connection to the web service running on the server. The protocol for establishing a connection is HTTP. HTTP means HyperText Transfer Protocol. Hyper Text Transfer Protocol is the basic protocol used by the World Wide Web. This protocol defines how messages are formatted and transmitted, and what actions should take by Web servers and web browsers in response to various commands.
The URL(Uniform Resource Locator) and URI(Uniform Resource Identifier) are the names the majority people used with the web addresses. If we want to open a web address http://fschub.com/ccna-study-guide.html we can examine how an address is opened in the browser.
- Protocol – HTTP
- Server Name – fschub.com
- The Specific filename which is requested ccna-study-guide.html
As shown in Figure, entering the mentioned URL in the browser, the browser then checks with a name server to convert fschub.com into a numeric IP address, which it uses to connect to the server. The browser then sends a GET request to the server using HTTP and asks for the ccna-study-guide.html file. The server then sends the HTML code of this particular page to the browser. In conclusion, the browser read the HTML code and formats the page for the browser window and show it to the user. The HTML is the main standard that controls how the World Wide Web works. It covers how the Web pages are formatted and displayed at the user screen.
HTTP and HTTPS
HTTP is a request/response protocol. When a client, sends a request to a web server, the protocol which specifies the message type is HTTP. There are three common message types are GET, POST, and PUT.
GET – A host request for data, generally a webpage request
POST – Uploads data files to the web server
PUT – Uploads resources or content to the web server such as an image, video, and audio.
Hypertext transfer protocol is extraordinarily protocol but it is not secure. The HTTP send request messages to the server in plain text that can be intercepted and read anywhere in the way. The responded HTML pages are also in unencrypted and unsecured pages.
To secure communication across the internet the HTTPS protocol is used which is too secure from Hypertext transfer protocol. This protocol uses authentication and encryption to secure data traveling between the client and server. it uses the same client request-server response process as HTTP; but the data travel between client and server is encrypted with SSL (Secure Socket Layer)