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.