Introduction Chapter 1 Introduction to Routing and Packet Forwarding Objectives Key Terms Inside the Router Routers Are Computers Routers Are at the Network Center Routers Determine the Best Path Router CPU and Memory CPU RAM ROM Flash Memory NVRAM Internetwork Operating System (IOS) Router Bootup Process Bootup Process Command-Line Interface Verifying Router Bootup Process IOS Version ROM Bootstrap Program Location of IOS CPU and Amount of RAM Interfaces Amount of NVRAM Amount of Flash Configuration Register Router Ports and Interfaces Management Ports Router Interfaces Interfaces Belong to Different Networks Example of Router Interfaces Routers and the Network Layer Routing Is Forwarding Packets Routers Operate at Layers 1, 2, and 3 CLI Configuration and Addressing Implementing Basic Addressing Schemes Populating an Address Table Basic Router Configuration Host Name and Passwords Configuring a Banner Router Interface Configuration Each Interface Belongs to a Different Network Verifying Basic Router Configuration Building the Routing Table Introducing the Routing Table show ip route Command Directly Connected Networks Static Routing When to Use Static Routes Dynamic Routing Automatic Network Discovery Maintaining Routing Tables IP Routing Protocols Routing Table Principles Asymmetric Routing Path Determination and Switching Functions Packet Fields and Frame Fields Internet Protocol (IP) Packet Format MAC Layer Frame Format Best Path and Metrics Best Path Comparing Hop Count and Bandwidth Metrics Equal-Cost Load Balancing Equal-Cost Paths Versus Unequal-Cost Paths Path Determination Switching Function Path Determination and Switching Function Details Path Determination and Switching Function Summary Summary Labs Check Your Understanding Challenge Questions and Activities To Learn More End Notes Chapter 2 Static Routing Objectives Key Terms Routers and the Network Role of the Router Introducing the Topology Examining the Connections of the Router Router Connections Serial Connectors Ethernet Connectors Router Configuration Review Examining Router Interfaces Interfaces and Their Statuses Additional Commands for Examining Interface Status Configuring an Ethernet Interface Configuring an Ethernet Interface Unsolicited Messages from IOS Reading the Routing Table Routers Usually Store Network Addresses Verifying Ethernet Addresses Commands to Verify Interface Configuration Ethernet Interfaces Participate in ARP Configuring a Serial Interface Examining Serial Interfaces Physically Connecting a WAN Interface Configuring Serial Links in a Lab Environment Verifying the Serial Interface Configuration Exploring Directly Connected Networks Verifying Changes to the Routing Table Routing Table Concepts Observing Routes as They Are Added to the Routing Table Changing an IP Address Devices on Directly Connected Networks Accessing Devices on Directly Connected Networks Pings from R2 to 172.16.3.1 Pings from R2 to 192.168.1.1 Cisco Discovery Protocol (CDP) Network Discovery with CDP Layer 3 Neighbors Layer 2 Neighbors CDP Operation Using CDP for Network Discovery CDP show Commands Disabling CDP Static Routes with "Next-Hop" Addresses Purpose and Command Syntax of the ip route Command ip route Command Configuring Static Routes Verifying the Static Route Configuring Routes to Two More Remote Networks Routing Table Principles and Static Routes Applying the Principles Resolving to an Exit Interface with a Recursive Route Lookup Exit Interface Is Down Static Routes with Exit Interfaces Configuring a Static Route with an Exit Interface Static Route and an Exit Interface Static Routes and Point-to-Point Networks Modifying Static Routes Verifying the Static Route Configuration Verifying Static Route Changes Static Routes with Ethernet Interfaces Ethernet Interfaces and ARP Sending an ARP Request Static Routes and Ethernet Exit Interfaces Advantages of Using an Exit Interface with Static Routes Summary and Default Static Routes Summary Static Routes Summarizing Routes to Reduce the Size of the Routing Table Route Summarization Calculating a Summary Route Configuring a Summary Route Default Static Route Most Specific Match Configuring a Default Static Route Verifying a Default Static Route Managing and Troubleshooting Static Routes Static Routes and Packet Forwarding Static Routes and Packet Forwarding Troubleshooting a Missing Route Troubleshooting a Missing Route Solving the Missing Route Summary Labs Check Your Understanding Challenge Questions and Activities To Learn More Floating Static Routes Discard Route Further Reading on Static Routing End Notes Chapter 3 Introduction to Dynamic Routing Protocols Objectives Key Terms Introduction to Dynamic Routing Protocols Perspective and Background Evolution of Dynamic Routing Protocols Role of Dynamic Routing Protocol Network Discovery and Routing Table Maintenance Purpose of Dynamic Routing Protocols Dynamic Routing Protocol Operation Dynamic Routing Protocol Advantages Static Routing Usage, Advantages, and Disadvantages Dynamic Routing Advantages and Disadvantages Classifying Dynamic Routing Protocols IGP and EGP Distance Vector and Link-State Routing Protocols Distance Vector Routing Protocol Operation Link-State Protocol Operation Classful and Classless Routing Protocols Classful Routing Protocols Classless Routing Protocols Dynamic Routing Protocols and Convergence Metrics Purpose of a Metric Metrics and Routing Protocols Metric Parameters Metric Field in the Routing Table Load Balancing Administrative Distance Purpose of Administrative Distance Multiple Routing Sources Purpose of Administrative Distance Dynamic Routing Protocols and Administrative Distance Static Routes and Administrative Distance Directly Connected Networks and Administrative Distance Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More Chapter 4 Distance Vector Routing Protocols Objectives Key Terms Introduction to Distance Vector Routing Protocols Distance Vector Technology Meaning of Distance Vector Operation of Distance Vector Routing Protocols Routing Protocol Algorithms Routing Protocol Characteristics Comparing Routing Protocol Features Network Discovery Cold Start Initial Exchange of Routing Information Exchange of Routing Information Convergence Routing Table Maintenance Periodic Updates Maintaining the Routing Table RIP Timers Bounded Updates Triggered Updates Random Jitter Routing Loops Defining a Routing Loop Implications of Routing Loops Count-to-Infinity Condition Preventing Routing Loops by Setting a Maximum Metric Value Preventing Routing Loops with Hold-Down Timers Preventing Routing Loops with the Split Horizon Rule Route Poisoning Split Horizon with Poison Reverse Preventing Routing Loops with IP and TTL Distance Vector Routing Protocols Today RIP and EIGRP RIP EIGRP Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More Chapter 5 RIP Version 1 Objectives Key Terms RIPv1: Distance Vector, Classful Routing Protocol Background and Perspective RIPv1 Characteristics and Message Format RIP Characteristics RIP Message Format: RIP Header RIP Message Format: Route Entry Why Are So Many Fields Set to Zero? RIP Operation RIP Request/Response Process IP Address Classes and Classful Routing Administrative Distance Basic RIPv1 Configuration RIPv1 Scenario A Enabling RIP: router rip Command Specifying Networks Verification and Troubleshooting Verifying RIP: show ip route Command Verifying RIP: show ip protocols Command Verifying RIP: debug ip rip Command Passive Interfaces Unnecessary RIP Updates Impact Network Stopping Unnecessary RIP Updates Automatic Summarization Modified Topology: Scenario B Boundary Routers and Automatic Summarization Processing RIP Updates Rules for Processing RIPv1 Updates Example of RIPv1 Processing Updates Sending RIP Updates: Using debug to View Automatic Summarization Advantages and Disadvantages of Automatic Summarization