List of Figures

Figure 1: TCP/IP Conceptual Layers

Figure 2: IP Address Classes

Figure 3: Basic Network Masking

Figure 4: Subnetting

Figure 5: Routing With and Without CIDR

Figure 6: Direct Next Hops

Figure 7: Indirect Next Hops

Figure 8: Sample ARP Process—1 through 3

Figure 9: Sample ARP Process—4 and 5

Figure 10: Routers in a Small Network

Figure 11: Static Routes with Indirect Next Hops

Figure 12: Sample Configuration for Next-Hop Verification

Figure 13: IPv4 and IPv6 Header Comparison

Figure 14: Direct Next Hops

Figure 15: Indirect Next Hops

Figure 16: OSPF Topology

Figure 17: Optimizing OSPF Area Aggregate Costs

Figure 18: Overview of IS-IS Topology

Figure 19: Packet Flow Between Routers With and Without Authentication Set

Figure 20: Example of Level 1 and Level 2 Routing

Figure 21: Transit Router Topology