Network Layer

The  internet  network  layer is  responsible  for moving  network  layer  packets  known data grams  from one host to another. The internet transport  layer protocol( TCP or UDP) in a source  host which  passes a transport  layer segment and a destination address to the  network  layer. The  network  layer then provides  the service  of delivering the segment  to  the transport  layer  of the  destination host.

The internet  networks  layer has two  principle  components. It  has protocol  that defines  the fields  in the datagram as well as how the end systems and routers act on these fields. This protocol is the celerity IP protocol. There is only one IP protocol and  all internet components that have a network layer must run the IP protocol. The  datagram's take between  sources and destinations. Although the network layer contains  both the IP protocol and numerous routing protocols. It is often simply  referred to as the IP layer reflecting  the fact  that IP  is the  glue  that binds  the internet together.