In: Computer Science
5)SOCKET:
Sockets in general allows the communication between two different
processes on the same machine or
different machines.It is one endpoint in a communication flow between two programs or processes
running over a network.
Sockets are created and used with a set of programming requests also called as "function calls" in
which sometimes referred as the sockets application programming interface (API). The most common
sockets API is the Berkeley UNIX C interface for sockets.
6)IDENTIFIER:
Identifiers in general are the symbols used to uniquely identify a
program element in the code.
They are also used to refer to types, constants, macros and parameters. An identifier name
particularlyn should indicate the synonym and usage of
the element that is being referred.
In some other cases,identifiers are referred as the names given to
the variables,constants and
functions.
7)An application layer protocol defines how an application processes that is running on different
end systems and pass messages to each other.The messages present in this layer are request messges
and response messages.
8)A transport layer protocol provides for logical communication
between application processes
running on different hosts.The transport level provides end-to-end communication between processes
executing on different machines.
9)Transport protocols relies or depends on the service
provided by the network layer. On the
Internet, the network layer provides a connectionless service. The network layer identifies each
host by using an IP address and enables hosts to transmit packets that contain up to 64 KBytes of
payload to any destination reachable through the network.
Transmission Control Protocol:
TCP is a connection oriented protocol and offers end-to-end packet
delivery and acts as back bone
for connection.It is a reliable and connection oriented protocol.Some of its features are:
Stream Data Transfer
Reliability
Efficient Flow Control
Full-duplex operation
Multiplexing
10)Application layer protocols:
The following are the some of the application layer
protocols.
1.SMTP-Simple Mail Transfer Protocol:
a.One of the most popular network service.
b.SMTP transfers messages from senders' mail servers to the recipients' mail servers using TCP
connections.
c.The TCP/IP protocol that supports electronic mail on the Internet is called Simple Mail Transfer
Protocol (SMTP).
2.FTP-File Transfer Protocol:
a.FTP is the standard mechanism provided which is provided by TCP/IP for copying a file from one
host to another.
b.FTP differs form other client-server applications because it establishes 2 connections between
hosts.One connection is used for data transferring and the other is used for the control of
information.
3.HTTP-Hyper Text Transfer Protocol:
a.This is a protocol used mainly to access data on the World Wide Web (www).
b.This protocol transfers data in the form of plain text, hyper text, audio, video and in many other
methods also.
c.HTTP utilizes TCP connections to send client requests and to receive server replies.
4.TELNET-Terminal Network:
TELNET is client-server application that allows a user to log onto remote machine and lets the user
to access any application program on a remote computer.Many of the application protocols are built
using this protocol i.e.,TELNET.
11)As mentioned HTTP is a stateless request-response based
communication protocol. It is used to
send and receive data on the the Internet. This protocol uses reliable TCP connections either for
the transfer of data to and from clients which are Web Browsers.
The main connections that are present are:
a.HTTP request
b.HTTP response
a.HTTP request in turn contains:
->HTTP Request Method, URI, and Protocol
Version
This should be the first line of an HTTP Request.
->HTTP Request Headers
Used to communicate information about the client
environment.
->HTTP Request Body
Contains the actual request being that is being sent to the HTTP
Server.
b.HTTP response:
->Protocol/Version, Status Code, and its
Description
A status code of 200 means the processing of request was successful
and the description in this
case will be 'OK'. Similarly, a status code of '404' means the file requested was not found at the
HTTP Server.
->HTTP response header
Contains useful infomation about the server
environment.
->HTTP response body
Contains the actual information that is rendered at the client
side.
13)Cookies:
These are generally small files which are stored on
the user's computer.In a different manner,it
records or saves your preferences when using a particular site.
14)Proxy server:
A proxy server is a computer that offers a service to
allow clients to make indirect network
connections to the other network services. A client connects to the proxy server, then requests a
connection, file, or other resource available on a
different server.
Then the proxy provides the required resource either
by connecting to the specified server or by
obtaining through its cache.
15)FTP:
FTP means "File Transfer Protocol"
a.FTP is the standard mechanism provided which is provided by TCP/IP for copying a file from one
host to another.
b.FTP differs form other client-server applications because it establishes 2 connections between
hosts.One connection is used for data transferring and the other is used for the control of
information.