Explain TCPIP layering and why we use layers 2 and 3 so much

Explain TCP/IP layering and why we use layers 2 and 3 so much in networking?

Solution

The four layers of TCP/IP layering are:

Application Layer

This layer provides network services to applications. Application network processes and protocols that work at this layer are namely : HyperText Transfer Protocol (HTTP), Simple Mail Transport Protocol (SMTP) and File Transfer Protocol (FTP).

Sockets and port numbers are used to differentiate the path and sessions which applications operate.

Transport Layer

The purpose of this layer is to transmitt data. The two main protocols that operate at this layer are Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). TCP is regarded as being the reliable transmission protocol and it guarantees that the proper data transfer will take place.

The Internet Layer

This layer contains the packet construct that will be transmitted.
This takes the form of the Internet Protocol (IP) which boxes a packet containing a source IP Address, destination IP Address and the actual data to be delivered.

Network Access Layer

This is the lowest level of the TCP/IP protocol. This layer is mainly used to include encapsulation of IP packets into frames for transmission, mapping IP addresses to physical hardware addresses (MAC Addresses) and the use of protocols for data transmission.

Internet layer and Transmission layer are used much for networking as both of them are related to the transmission of data thorugh packet system.

Layer 2 i.e. Internet layer forms the data packet and also the IP address of source and destination to be delivered. Thus this layer forms the data packet with the rquired address.

Whereas the next layer i.e. the Transmission layer used to transfer the data packet formed in layer 2 through TCP