Transmission Control Protocol / Internet Protocol (TCP/IP)
TCP/IP Model or Transmission Control Protocol / Internet Protocol (TCP/IP) - The TCP/IP Model divides networking functions into discrete layers. In this model each layer does a specific function and is transparent to the layer above it and the layer below it. The primary function of TCP/IP model is to conceptualize how network should work, so that hardware and network protocols can communicate in fluent way. The TCP/IP model is one of the best conceptual model after the OSI Model. In this model the subsequent layers which are used to describe and illustrate TCP/IP is given below.
- Link – It is required to deliver data across a physical network.
- Internet – It is for the logical transmission of packets across the network.
- Transport – It provide rules for establishing level of transmission service for applications. It is responsible for reliable transmission of data and delivery of packets error free.
- Application – It provide rules for node-to-node communication of application and provide services to the application software which execute on computer.
The more information related to TCP/IP network model in given here.
The TCP/IP network model is divided into four layers/ Sections:
Application Layer - The Application Layer provides user an interface to communicate and access the applications. This interface may be web browser, e-mail client, a file transfer client. The application layer is concerned with providing network services to applications present on host as well as remote computer. There are various network process and protocol that works on this layer like - Hypertext Transfer Protocol (HTTP), Simple Mail Transport Protocol (SMTP), File Transfer Protocol (FTP), etc.
Transport Layer - The Transport Layer enables the means for the transportation of data segments across the Internet Layer. The Transport Layer is also concerned with end-to-end or host to host or peer to peer communication. Transmission Control Protocol (TCP) provides reliable connection-oriented transport of data between two computers that use Internet Protocol to communicate, it guarantees that the proper data transfer will take place. User Datagram Protocol (UDP) provides unreliable, connectionless transport of data between two endpoints on two computers that use Internet Protocol to communicate, but it does not guarantee.
Internet Layer – In this layers packets are transferred from one node to another. This layer contains packet which are transmitted from one computer to another. The internet layer uses Internet address which is described as the packet that contains a source IP Address, destination IP Address and the original data to be delivered. The Internet Layer is responsible for routing of data, packetiszation and addressing on the network. Internet Protocol (IP) uses the packetization, logical addressing and routing functions that forward packets from one computer to another.
Network Layer –It is the lowest level of the TCP/IP protocol stack and encapsulation of IP packets into frames for transmission, mapping IP addresses to physical hardware addresses (MAC Addresses) and physical transmission of data is carried out. The Network Layer provides access to the real physical network. The hardware or interface include Network interface Card (NIC), Token Ring, ATM, OC, HSSI, Ethernet, FDDI, and Wi-Fi. The purpose of a network interface card is to access the wire, wireless or fibre optic network and transmit data to other computers. Transmission Control Protocol / Internet Protocol (TCP/IP) is over.