Each layer of TCP/IP protocol stack, has its own set of functionalities and provides a set of services to the next layer.The descriptions of these layers are, (Blank, TCP/IP Foundations, 2006) Network interface layer or network access layer is the lowest layer in the TCP/IP protocol stack.
The main function is to provide address resolution services to the network layer.
Internet control message protocol provides different types of diagnosis and error handling services that may occur from erroneous packet delivery.
Internet layer is responsible for packaging, addressing and routing of packets. Each of these protocols performs different types of responsibilities and collectively all these are the responsibilities of internet layer.
(Comer, 2006) Internet protocol is responsible for routing packets.
Internet group management protocol manages groups of IP multi-casting.
Transport layer provided host to host service on the top of internet layer.
It is anticipated this will both reduce operational costs and increase network efficiency. The Business Case should; TCP/IP architecture model was initially designed as DARPA model by the US government agency by that name. Those were, application layer, transport layer, Internet layer and network interface layer.
Each of those layer used to correspond to one or more layers in the OSI model with seven layers.
("TCP/IP Internet Protocol.") Robert Kahn and Vinton Cerf are the designers of TCP/IP.
However, Kahn was the one who laid the open architecture foundations for TCP/IP, which provided the Internet with one of its most distinctive features.