HTTP
o HTTP stands for HyperText Transfer Protocol.
o It is a protocol used to access the data on the World Wide Web (www).
o The HTTP protocol can be used to transfer the data in the form of plain text,
hypertext, audio, video, and so on.
o This protocol is known as HyperText Transfer Protocol because of its
efficiency that allows us to use in a hypertext environment where there are
rapid jumps from one document to another document.
o HTTP is similar to the FTP as it also transfers the files from one host to
another host. But, HTTP is simpler than FTP as HTTP uses only one
connection, i.e., no control connection to transfer the files.
o HTTP is used to carry the data in the form of MIME-like format.
o HTTP is similar to SMTP as the data is transferred between client and server.
The HTTP differs from the SMTP in the way the messages are sent from the
client to the server and from server to the client. SMTP messages are stored
and forwarded while HTTP messages are delivered immediately.
Features of HTTP:
o Connectionless protocol: HTTP is a connectionless protocol. HTTP client
initiates a request and waits for a response from the server. When the server
receives the request, the server processes the request and sends back the
response to the HTTP client after which the client disconnects the connection.
The connection between client and server exist only during the current
request and response time only.
o Media independent: HTTP protocol is a media independent as data can be
sent as long as both the client and server know how to handle the data
content. It is required for both the client and server to specify the content
type in MIME-type header.
o Stateless: HTTP is a stateless protocol as both the client and server know
each other only during the current request. Due to this nature of the protocol,
both the client and server do not retain the information between various
requests of the web pages.
HTTP Transactions
The above figure shows the HTTP transaction between client and server. The client
initiates a transaction by sending a request message to the server. The server
replies to the request message by sending a response message.
Messages
HTTP messages are of two types: request and response. Both the message types
follow the same message format.
Request Message: The request message is sent by the client that consists of a
request line, headers, and sometimes a body.
Response Message: The response message is sent by the server to the client that
consists of a status line, headers, and sometimes a body.
Uniform Resource Locator (URL)
o A client that wants to access the document in an internet needs an address
and to facilitate the access of documents, the HTTP uses the concept of
Uniform Resource Locator (URL).
o The Uniform Resource Locator (URL) is a standard way of specifying any kind
of information on the internet.
o The URL defines four parts: method, host computer, port, and path.
o Method: The method is the protocol used to retrieve the document from a
server. For example, HTTP.
o Host: The host is the computer where the information is stored, and the
computer is given an alias name. Web pages are mainly stored in the
computers and the computers are given an alias name that begins with the
characters "www". This field is not mandatory.
o Port: The URL can also contain the port number of the server, but it's an
optional field. If the port number is included, then it must come between the
host and path and it should be separated from the host by a colon.
o Path: Path is the pathname of the file where the information is stored. The
path itself contain slashes that separate the directories from the
subdirectories and files.
HTTP HTTPS
The full form of HTTP is the The full form of HTTPS is Hypertext Transfer
Hypertext Transfer Protocol. Protocol Secure.
It is written in the address bar It is written in the address bar as https://.
as http://.
The HTTP transmits the data The HTTPS transmits the data over port number
over port number 80. 443.
It is unsecured as the plain text It is secure as it sends the encrypted data which
is sent, which can be accessible hackers cannot understand.
by the hackers.
It is mainly used for those It is a secure protocol, so it is used for those
websites that provide websites that require to transmit the bank
information like blog writing. account details or credit card numbers.
It is an application layer It is a transport layer protocol.
protocol.
It does not use SSL. It uses SSL that provides the encryption of the
data.
Google does not give the Google gives preferences to the HTTPS as
preference to the HTTP HTTPS websites are secure websites.
websites.
The page loading speed is fast. The page loading speed is slow as compared to
HTTP because of the additional feature that it
supports, i.e., security.
