Chapter 3: Working with ARP, the IP Communication Model, and Data Link Layer Troubleshooting
In This Chapter
Seeing the ARP process in action
Understanding how ANDing works and where it is used
Troubleshooting with ARP
Reviewing other ICMP-based troubleshooting tools
In earlier chapters, I show you the lower levels of the Open System Interconnection (OSI) model. I discuss how every network card on the network, whether integrated on computer motherboards, installed in printers, or found in your network routers, has a unique address that is used for network communications. This unique address — its Media Access Control (MAC) address — is used to identify each device on a network segment, between two routers, and may be filtered by switches or bridges. In general terms, all devices on that network segment will see all traffic on that segment. However, when a network device receives an Ethernet frame, it checks the destination address in the frames’ header; if the destination address referenced in the network frame is not a broadcast address, or their own address, the network device ...