... A+,Network+, Security+, I-Net+How Does Ping Really Work? Copyright ©2006 Global Knowledge Training LLC. All rights reserved.Page 2The layer above the Network Access layer, the Internetworking ... So, how does this work? BackgroundThe TCP/IP protocol stack is organized as a four-layer model (see Figure 1). The lowest layer, commonly calledthe Network Interface or Network Access layer, ... provides networkdiagnostic capabilities and feedback to those responsible for network administration and operation. See RFC792,if you are really interested.Above the Internetworking layer...