Routing Protocols and Concepts CCNA Exploration Companion Guide   Routing Protocols and Concepts, CCNA Exploration Companion Guide is the official supplemental textbook for the Routing Protocols and Concepts course in the Cisco Networking Academy® CCNA® Exploration curriculum version 4. This course describes the architecture, components, and operation of routers, and explains the principles of routing and the primary routing protocols. The Companion Guide, written and edited by Networking Academy instructors, is designed as a portable desk reference to use anytime, anywhere. The book’s features reinforce the material in the course to help you focus on important concepts and organize your study time for exams.   New and improved features help you study and succeed in this course: Chapter objectives–Review core concepts by answering the focus questions listed at the beginning of each chapter. Key terms–Refer to the updated lists of networking vocabulary introduced and turn to the highlighted terms in context in each chapter. Glossary–Consult the comprehensive glossary with more than 150 terms. Check Your Understanding questions and answer key–Evaluate your readiness with the updated end-of-chapter questions that match the style of questions you see on the online course quizzes. The answer key explains each answer. Challenge questions and activities–Strive to ace more challenging review questions and activities designed to prepare you for the complex styles of questions you might see on the CCNA exam. The answer key explains each answer.   Rick Graziani has been a computer science and networking instructor at Cabrillo College since 1994.    Allan Johnson works full time developing curriculum for Cisco Networking Academy. Allan also is a part-time instructor at Del Mar College in Corpus Christi, Texas.   How To–Look for this icon to study the steps you need to learn to perform certain tasks.   Packet Tracer Activities– Explore networking concepts in activities interspersed throughout some chapters using Packet Tracer v4.1 developed by Cisco®. The files for these activities are on the accompanying CD-ROM.   Also available for the Routing Protocols and Concepts Course: Routing Protocols and Concepts CCNA Exploration Labs and Study Guide ISBN-10: 1-58713-204-4 ISBN-13: 978-1-58713-204-9   Companion CD-ROM **See instructions within the ebook on how to get access to the files from the CD-ROM that accompanies this print book.** The CD-ROM provides many useful tools and information to support your education: Packet Tracer Activity exercise files v4.1 A Guide to Using a Networker’s Journal booklet Taking Notes: a .txt file of the chapter objectives More IT Career Information Tips on Lifelong Learning in Networking   This book is part of the Cisco Networking Academy Series from Cisco Press®. The products in this series support and complement the Cisco Networking Academy online curriculum.  

Table of Contents:
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         Advantages of Automatic Summarization         Disadvantage of Automatic Summarization         Discontiguous Topologies Do Not Converge with RIPv1 Default Route and RIPv1     Modified Topology: Scenario C     Propagating the Default Route in RIPv1 Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More Chapter 6 VLSM and CIDR Objectives Key Terms Classful and Classless Addressing     Classful IP Addressing         High-Order Bits         IPv4 Classful Addressing Structure     Classful Routing Protocol     Classless IP Addressing         Moving Toward Classless Addressing         CIDR and Route Summarization         Classless Routing Protocol VLSM     VLSM in Action     VLSM and IP Addresses CIDR     Route Summarization     Calculating Route Summarization Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More Chapter 7 RIPv2 Objectives Key Terms RIPv1 Limitations     Summary Route     VLSM     RFC 1918 Private Addresses     Cisco Example IP Addresses     Loopback Interfaces     RIPv1 Topology Limitations         Static Routes and Null Interfaces         Route Redistribution         Verifying and Testing Connectivity     RIPv1: Discontiguous Networks         Examining the Routing Tables         How Classful Routing Protocols Determine Subnet Masks     RIPv1: No VLSM Support     RIPv1: No CIDR Support         192.168.0.0/16 Static Route Configuring RIPv2     Enabling and Verifying RIPv2     Auto-Summary and RIPv2     Disabling Auto-Summary in RIPv2     Verifying RIPv2 Updates VLSM and CIDR     RIPv2 and VLSM     RIPv2 and CIDR Verifying and Troubleshooting RIPv2     Verification and Troubleshooting Commands         show ip route Command         show ip interface brief Command         show ip protocols Command         debug ip rip Command         ping Command         show running-config Command     Common RIPv2 Issues     Authentication Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More Chapter 8 The Routing Table: A Closer Look Objectives Key Terms The Routing Table Structure     Lab Topology     Routing Table Entries     Level 1 Routes     Parent and Child Routes: Classful Networks         Level 1 Parent Route         Level 2 Child Route     Parent and Child Routes: Classless Networks Routing Table Lookup Process     Steps in the Route Table Lookup Process         The Route Lookup Process     Longest Match: Level 1 Network Routes         Longest Match         Example: Level 1 Ultimate Route     Longest Match: Level 1 Parent and Level 2 Child Routes         Example: Level 1 Parent Route and Level 2 Child Routes         Example: Route Lookup Process with VLSM Routing Behavior     Classful and Classless Routing Behavior         Topology Changes     Classful Routing Behavior: no ip classless     Classful Routing Behavior: Search Process         Example: R2 Operating with Classful Routing Behavior     Classless Routing Behavior: ip classless         The Route Lookup Process     Classless Routing Behavior: Search Process         Example: R2 Operating with Classless Routing Behavior         Classful Route on R3         Classful vs. Classless Routing Behavior in the Real World Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More End Notes Chapter 9 EIGRP Objectives Key Terms Introduction to EIGRP     EIGRP: An Enhanced Distance Vector Routing Protocol         Roots of EIGRP: IGRP         The Algorithm         Path Determination         Convergence     EIGRP Message Format     Protocol-Dependent Modules     RTP and EIGRP Packet Types         EIGRP Packet Types     Hello Protocol     EIGRP Bounded Updates     DUAL: An Introduction     Administrative Distance     Authentication Basic EIGRP Configuration     EIGRP Network Topology     Autonomous Systems and Process IDs         Autonomous System         Process ID     The router eigrp Command     The network Command         The network Command with a Wildcard Mask     Verifying EIGRP     Examining the Routing Table         Introducing the Null0 Summary Route         R3 Routing Table EIGRP Metric Calculation     EIGRP Composite Metric and the K Values         The Composite Metric         Verifying the K Values     EIGRP Metrics         Examining the Metric Values         Bandwidth         Delay         Reliability         Load     Using the bandwidth Command     Calculating the EIGRP Metric         Bandwidth         Delay         Adding Bandwidth and Delay DUAL     DUAL Concepts     Successor and Feasible Distance     Feasible Successors, Feasibility Condition, and Reported Distance     Topology Table: Successor and Feasible Successor     Topology Table: No Feasible Successor     Finite State Machine         DUAL FSM         No Feasible Successor More EIGRP Configurations     The Null0 Summary Route     Disabling Automatic Summarization     Manual Summarization         Determining the Summary EIGRP Route         Configure EIGRP Manual Summarization     EIGRP Default Route     Fine-Tuning EIGRP         EIGRP Bandwidth Utilization         Configuring Hello Intervals and Hold Times Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More Chapter 10 Link-State Routing Protocols Objectives Key Terms Link-State Routing     Link-State Routing Protocols     Introduction to the SPF Algorithm     Link-State Routing Process     Step 1: Learning About Directly Connected Networks         Links         Link States     Step 2: Sending Hello Packets to Neighbors     Step 3: Building the Link-State Packet     Step 4: Flooding Link-State Packets to Neighbors     Step 5: Constructing a Link-State Database     Shortest Path First (SPF) Tree         Building the SPF Tree         Determining the Shortest Path         Generating a Routing Table from the SPF Tree Implementing Link-State Routing Protocols     Advantages of a Link-State Routing Protocol         Builds a Topological Map         Fast Convergence         Event-Driven Updates         Hierarchical Design     Requirements of a Link-State Routing Protocol         Memory Requirements         Processing Requirements         Bandwidth Requirements     Comparison of Link-State Routing Protocols Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More Chapter 11 OSPF Objectives Key Terms Introduction to OSPF     Background of OSPF     OSPF Message Encapsulation     OSPF Packet Types     Hello Protocol         Neighbor Establishment         OSPF Hello and Dead Intervals         Electing a DR and BDR     OSPF LSUs     OSPF Algorithm     Administrative Distance     Authentication Basic OSPF Configuration     Lab Topology     The router ospf Command     The network Command     OSPF Router ID         Determining the Router ID         Highest Active IP Address         Verifying the Router ID         Loopback Address         OSPF router-id Command         Modifying the Router ID         Duplicate Router IDs     Verifying OSPF     Examining the Routing Table The OSPF Metric     OSPF Metric         Reference Bandwidth         OSPF Accumulates Cost         Default Bandwidth on Serial Interfaces     Modifying the Cost of the Link         The bandwidth Command         The ip ospf cost Command         The bandwidth Command vs. the ip ospf cost Command OSPF and Multiaccess Networks     Challenges in Multiaccess Networks         Multiple Adjacencies         Flooding of LSAs         Solution: Designated Router     DR/BDR Election Process         Topology Change         DR/BDR Election         Timing of DR/BDR Election     OSPF Interface Priority More OSPF Configuration     Redistributing an OSPF Default Route         Topology     Fine-Tuning OSPF         Reference Bandwidth         Modifying OSPF Intervals Summary Activities and Labs Check Your Understanding Challenge Questions and Activities To Learn More Appendix Check Your Understanding and Challenge Questions Answer Key Glossary of Key Terms Index     1587132060    TOC    11/9/2007