while this may be a technicality....the names of the layers are wrong whether you are refering to the OSI model or the earlier model... Network Interface? I'm assuming that is the network layer and Genesis is the one who seems to have gotten it right. Top layers - Application, Presentation and Session send the datagram to the Transport layer which adds it's portion(TCP or UDP info), that becomes a segment which is passed to the Network Layers. This adds IP info in its header and it becomes a packet. This packet goes to the Datalink layer which adds a header and footer so it's called a frame which is converted to bits by the Physical layer.
this question has major issues as in the earlier model, think it was the DOD... the Network Layer is called the Internet layer so how would step one be carried out?