A REVIEW ON TCP/IP TECHNOLOGIES

Introduction

TCP/IP is set of an organized protocols in various layers that is used in the Internet these days. The TCP/IP model depicts a set of general design guidelines and implementations of specific networking protocols to enable host, large computer, laptop, workstation, cellular phone or security framework to communicate over the network. It has been structured hierarchically in order to provide functionality for lower level protocols to provide services to the upper level protocols.

IP & TCP

The Internet Protocol (IP) is the address system of the internet and has the core capacity of conveying packets of information from a source device to a target device. IP is the primary way in which network connections are made, and it builds up the basis of the internet. IP doesn’t deal with packet ordering or error checking. Such functionality requires another protocol, typically TCP.

The TCP/IP relationship is like sending someone a composed on a riddle through the mail. The message is written down and the riddle is broken into pieces. Each piece at that point can go through an alternate postal route, some of which take longer than others. At the point when the riddle pieces arrive after traversing their various paths, the pieces may be out of order. The Internet Protocol ensures that the pieces arrive at their destination address. The TCP protocol can be thought of as the riddle assembler on the other side who puts the pieces together in the right order, asks for missing pieces to be resent, and tells the sender the riddle has been received. TCP keeps up the connection with the sender from before the first riddle piece is sent to after the final piece is sent.

IP is a connectionless protocol, which implies that every unit of information is individually addressed and directed from the source device to the target device, and the target does not send an acknowledgement back to the source. That’s where protocols such as the Transmission Control Protocol (TCP) come in. TCP is used in conjunction with IP in order to keep up the connection between the sender and the target and to ensure packet order.

 

 

How TCP/IP works

TCP/IP uses the client/server model of communication in which a client (a user or machine) is provided a service (like sending a webpage) by another computer (a server) in the network.

Collectively, the TCP/IP suite of protocols is classified as stateless, which means every client request is considered new in line of the fact that it is irrelevant to previous requests. Being stateless frees up network paths so they can be used continuously.

The transport layer itself, however, is stateful. It transmits a single message, and its connection remains in place until all the packets in a message have been received and reassembled at the destination.

TCP/IP

Application Layer

Transport Layer

Network Layer

Physical Layer

Fig 1: The Layers in TCP/IP model

The application layer provides applications with standardized data exchange. Its protocols include the Hypertext Transfer Protocol (HTTP), File Transfer Protocol (FTP), Post Office Protocol 3 (POP3), Simple Mail Transfer Protocol (SMTP) and Simple Network Management Protocol (SNMP).

The transport layer is responsible for keeping up end-to-end communications over the network. TCP handles communications between hosts and provides flow control, multiplexing and reliability. The transport protocols include TCP and User Datagram Protocol (UDP), which is sometimes used instead of TCP for specific purposes.

The network layer, also called the internet layer, deals with packets and connects independent networks to transport the packets over network boundaries. The network layer protocols are the IP and the Internet Control Message Protocol (ICMP), which is used for error reporting.

The physical layer comprises of protocols that operate only on a link -- the network component that interconnects nodes or hosts in the network. The protocols in this layer include Ethernet for local area networks (LANs) and the Address Resolution Protocol (ARP).