Introduction To TCP/IP Model ( DOD Model) – Part 1
The TCP/IP model was created by Department Of Defence(DOD).If you have read my previous posts about the OSI model introduction then you can see that the OSI model has 7 layers whereas in the TCP/IP model there are only 4 layers.
The 4 layers in the TCP/IP model are
- Host to Host
- Network Access
1.)Application layer-This layer is equivalent to the top 3 three layers of the OSI model .This layer is responsible for defining node to node application communication and user interfaces.The protocols used are tftp,snmp,dns etc.
2.)Host to Host-This performs the same functionality as that of the transport layer in the osi model.It is responsible for creating end to end communications.It also checks data integrity and maintains packet sequencing.The protocols used are TCP and UDP.
3.)Internet-Now this layer’s functionality corresponds to network layer i.e. it takes care of addressing and routing of packets.The protocols used are IP,ICMP,ARP,RARP
4.)Network Access-This is the physical layer it is composite of DLL(data link layer) and the physical layer .It defines physical transmission norms for transmission of data .Technology used Ethernet,FDDI, ATM,Token Ring etc.