In this section, we will take a look at various vulnerabilities that exist at the Network Access/Link layer of the TCP/IP stack. As you learned in a previous chapter, the Network Access/Link Layer of the TCP/IP stack has the equivalence of the both the Data Link and Physical Layers of the OSI reference model:
As we learned in the early parts of this book, the Data Link Layer (layer 2) is responsible for the error checking, reassembly of frames, delivery of frames, Media Access Control (MAC) addressing, flow control of frames as they are sent and received on the network. The Physical Layer (layer 1) is responsible for the electrical and mechanical functions: for delivering the bits from one device to another. As the name suggests, the Physical Layer is the physical media used for transmission of the bits, such as the cables, hubs...