Layers 7 through 4 are geared more to the application than ... The most ubiquitous example is the IP protocol in TCP/IP (see TCP/IP). IPX, SNA and AppleTalk are examples of earlier routable ...
Ethernet is a layer 2 data link protocol that is widely used with the TCP/IP ... and 4. To understand network communications, it is essential to learn about the protocol layers (see OSI model).