IP Routing Protocols: Fundamentals and Distance-Vector Routing Protocols |
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xv | |
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xxi | |
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Chapter 1 Introduction to IP Routing Protocols |
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1 | (24) |
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1.1 Why We Need Routing Protocols |
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1 | (1) |
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1 | (10) |
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1.2.1 Directly Connected Interface |
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2 | (1) |
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3 | (1) |
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4 | (1) |
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1.2.3.1 Default Route for an IP Host |
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4 | (1) |
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1.2.3.2 Default Route in a Router |
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4 | (1) |
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1.2.4 Dynamic Routing Protocols |
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5 | (6) |
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8 | (1) |
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1.2.4.2 Periodic versus Triggered Routing Updates |
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8 | (1) |
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1.2.4.3 Routing Information Authentication |
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9 | (1) |
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1.2.4.4 Routing Information and Network Convergence |
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10 | (1) |
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11 | (4) |
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1.3.1 What Is a Network Prefix and a Route? |
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11 | (1) |
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1.3.2 Autonomous System Numbers (ASNs) |
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12 | (1) |
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1.3.3 Multiple Routing Domains in an Autonomous System |
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13 | (1) |
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1.3.4 Types of Autonomous Systems |
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14 | (1) |
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1.4 Routing Metrics and Costs |
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15 | (5) |
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15 | (2) |
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1.4.1.1 Network Diameter: Maximum Hop Count |
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16 | (1) |
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1.4.1.2 "Infinity" Hop Count as a Signaling Mechanism for Network Failures |
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17 | (1) |
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1.4.1.3 Limitations of the Hop Count as a Routing Metric |
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17 | (1) |
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17 | (1) |
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18 | (1) |
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18 | (1) |
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18 | (1) |
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19 | (1) |
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1.4.6.1 Example: OSPF Cost |
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19 | (1) |
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1.4.6.2 Cost Based on Interface Bandwidth |
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19 | (1) |
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1.5 Classification of Routing Protocols |
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20 | (2) |
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1.5.1 Interior versus Exterior Routing Protocols |
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21 | (1) |
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22 | (2) |
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24 | (1) |
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24 | (1) |
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Chapter 2 Types of Dynamic Routing Protocols |
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25 | (52) |
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25 | (1) |
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2.2 Distance-Vector Routing Protocols |
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25 | (19) |
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2.2.1 Basic Characteristics of Distance-Vector Routing Protocols |
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25 | (5) |
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2.2.2 Distance-Vector Routing Protocol Operations |
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30 | (1) |
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2.2.3 What Is a Rooting Loop? |
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31 | (1) |
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2.2.4 Routing Loops and Workarounds - Enhancing the Performance of Distance-Vector Routing Protocols |
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32 | (12) |
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2.2.4.1 Initial Full Routing Table Update and Periodic Updates |
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33 | (1) |
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2.2.4.2 Route Maintenance and Invalidation Timers |
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34 | (2) |
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36 | (2) |
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2.2.4.4 Triggered Updates |
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38 | (1) |
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2.2.4.5 Count-to-Infinity (Maximum Hop Count) |
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39 | (2) |
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41 | (1) |
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42 | (2) |
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2.3 Link-State Routing Protocols |
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44 | (13) |
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2.3.1 OSPF versus IS-IS Metrics |
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45 | (1) |
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2.3.2 Basic Characteristics of Link-State Routing Protocols |
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46 | (1) |
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2.3.3 Link-State Routing Protocol Operations |
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47 | (10) |
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2.3.3.1 Neighbor Discovery |
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48 | (2) |
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2.3.3.2 Link-State Flooding |
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50 | (1) |
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2.3.3.3 Link-State Database |
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51 | (1) |
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2.3.3.4 Link-State Routing Process |
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52 | (1) |
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2.3.3.5 Calculating the Shortest Paths and Constructing the Routing Table |
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53 | (3) |
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56 | (1) |
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2.4 Path-Vector Routing Protocols |
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57 | (11) |
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2.4.1 Why an IGP Is Not Recommended for Routing between Routing Domains or Autonomous Systems |
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58 | (2) |
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2.4.2 Using an EGP between Routing Domains: Path-Vector Routing Protocol |
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60 | (2) |
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2.4.3 BGP: A Path-Vector Routing Protocol |
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62 | (4) |
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2.4.3.1 Internal and External BGP Peering |
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63 | (1) |
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2.4.3.2 Basic Characteristics of BGP Routes |
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63 | (2) |
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2.4.3.3 BGP Autonomous System Path Advertisement |
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65 | (1) |
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2.4.3.4 Loop-Free Paths within an Autonomous System |
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65 | (1) |
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2.4.3.5 Manually Configured BGP Connections over TCP |
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65 | (1) |
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2.4.4 BGP and Path Attributes |
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66 | (2) |
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2.5 The IP Routing Table and Selection of Best Paths |
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68 | (5) |
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2.5.1 Path Metrics and Routing Protocols |
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68 | (1) |
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2.5.1.1 Equal-Cost Multipath (ECMP) Routing |
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69 | (1) |
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2.5.2 Administrative Distance and Route Selection |
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69 | (2) |
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2.5.2.1 Administrative Distance Use Case Example |
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70 | (1) |
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2.5.3 Prefix Length and Longest Prefix Matching Lookup |
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71 | (2) |
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73 | (1) |
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74 | (3) |
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Chapter 3 Routing and Forwarding Tables in Routing Devices |
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77 | (22) |
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77 | (1) |
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3.2 Functional Components of an IP Router |
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77 | (3) |
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3.2.1 IP Control Engine (or Route Processor) |
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77 | (2) |
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3.2.2 IP Forwarding Engine |
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79 | (1) |
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3.3 High-Level Router Architectures |
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80 | (5) |
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3.3.1 Router Architectures with Centralized Forwarding Engine |
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80 | (1) |
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3.3.2 Router Architecture with Multiple Centralized Forwarding Engines |
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81 | (1) |
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3.3.3 Router Architecture with Distributed Forwarding Engines |
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82 | (2) |
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3.3.4 Control Plane Redundancy |
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84 | (1) |
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3.4 IP Routing and Forwarding Tables |
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85 | (7) |
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85 | (6) |
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3.4.1.1 Routing Table Entries |
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85 | (3) |
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3.4.1.2 Routing Tables in a Router with Multiple Protocols |
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88 | (2) |
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3.4.1.3 Types of Unicast Routing Tables |
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90 | (1) |
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3.4.1.4 Aggregate or Summary Routes in the Routing Table |
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91 | (1) |
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91 | (1) |
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3.5 A Note on Layer 2. Adjacency Table |
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92 | (1) |
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3.6 IP Forwarding Operations |
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92 | (3) |
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3.6.1 Handling Special Addresses During Packet Forwarding |
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94 | (1) |
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3.7 Redistributing Routing Information and Routing Metric Translation |
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95 | (2) |
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3.7.1 The Need for Route Redistribution |
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95 | (1) |
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3.7.2 Filtering Inbound and Outbound Routing Information |
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95 | (1) |
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3.7.3 The Need for Routing Metric Translation |
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96 | (1) |
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97 | (1) |
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98 | (1) |
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Chapter 4 Static Routes in the Routing Table |
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99 | (16) |
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99 | (1) |
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4.2 Benefits of Dynamic Routing Protocols |
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99 | (1) |
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4.3 Benefits of Static Routing |
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100 | (3) |
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4.4 Configuring Dynamic Routing versus Static Routing |
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103 | (1) |
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4.5 Standard Static Route |
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104 | (2) |
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4.5.1 Concept of Qualified Next Hop |
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105 | (1) |
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106 | (2) |
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108 | (3) |
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4.8 Floating Static Route |
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111 | (2) |
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113 | (1) |
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113 | (2) |
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Chapter 5 Routing Information Protocol (RIP) |
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115 | (32) |
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115 | (1) |
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5.2 Routing Protocols and Their Databases |
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115 | (2) |
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117 | (1) |
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5.4 RIPv2 Message Format and Other Characteristics |
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117 | (5) |
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5.4.1 RIPv2 Message Format |
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118 | (1) |
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5.4.2 Interpreting the Address Family Identifier (AFI) Field in RIPv2 |
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119 | (1) |
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5.4.3 RIPv2 Routing Table |
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120 | (1) |
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120 | (1) |
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5.4.5 RIPv2 Request Message |
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120 | (1) |
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5.4.6 RIPv2 Response Messages |
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121 | (1) |
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5.4.7 Sending and Receiving RIPv2 Request and Response Messages |
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122 | (1) |
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122 | (6) |
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5.5.1 Plaintext Authentication |
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123 | (1) |
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5.5.2 Cryptographic Authentication |
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124 | (4) |
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5.5.2.1 RIPv2 Authentication Message Generation |
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126 | (1) |
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5.5.2.2 RIPv2 Authentication Message Reception |
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127 | (1) |
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5.6 High-Level RIP Router Architecture, Processes, and Databases |
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128 | (12) |
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129 | (1) |
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5.6.2 The Management Process |
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129 | (8) |
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5.6.2.1 The Route Store Process |
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131 | (1) |
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5.6.2.2 The Interface Manager |
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132 | (2) |
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5.6.2.3 The Sockets Manager |
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134 | (3) |
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5.6.2.4 The Redistribution Manager |
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137 | (1) |
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5.6.3 The Routing Table Manager Process |
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137 | (3) |
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5.7 Filtering Routing Updates in RIP |
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140 | (2) |
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5.7.1 Configuration of Passive Interface to Prevent or Restrict Routing Updates |
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140 | (1) |
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5.7.2 Filtering Routes in Incoming and Outgoing Routing Updates |
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141 | (8) |
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5.7.2.1 Distribute-list In |
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141 | (1) |
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5.7.2.2 Distribute-list Out |
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142 | (1) |
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5.8 Summary of RIPv2 Features |
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142 | (2) |
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144 | (1) |
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144 | (3) |
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Chapter 6 Enhanced Interior Gateway Routing Protocol (EIGRP) |
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147 | (62) |
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147 | (1) |
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147 | (2) |
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149 | (6) |
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6.3.1 Reliable Transport Protocol |
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149 | (2) |
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6.3.2 Main EIGRP Databases |
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151 | (3) |
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151 | (1) |
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152 | (1) |
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153 | (1) |
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6.3.2.4 Other EIGRP Concepts |
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154 | (1) |
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154 | (1) |
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155 | (10) |
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157 | (2) |
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159 | (1) |
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159 | (1) |
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160 | (1) |
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161 | (1) |
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161 | (2) |
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163 | (2) |
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165 | (2) |
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6.6 Feasible and Reported Distance |
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167 | (1) |
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167 | (1) |
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6.6.2 Reported (or Advertised) Distance |
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167 | (1) |
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6.7 Successor and Feasible Successor |
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168 | (4) |
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168 | (2) |
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170 | (2) |
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6.8 Route States: ACTIVE and PASSIVE States |
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172 | (3) |
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172 | (1) |
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173 | (1) |
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6.8.3 Comments on Feasible Successors when a Route Is in the PASSIVE or ACTIVE State |
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174 | (1) |
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6.9 Feasibility Condition |
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175 | (1) |
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6.10 EIGRP Diffusing Update Algorithm (DUAL) |
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176 | (5) |
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6.10.1 High-Level Description of DUAL |
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176 | (1) |
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6.10.2 Message Types Used by DUAL |
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177 | (1) |
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6.10.3 Some Behaviors of DUAL |
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178 | (1) |
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6.10.4 Stuck-In-Active (SIA) and the Use of SIA-QUERY and SIA-REPLY Messages |
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179 | (2) |
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6.10.4.1 Stuck-In-Active (SIA) |
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179 | (1) |
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180 | (1) |
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181 | (1) |
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6.11 EIGRP Neighbor Discovery and Maintenance |
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181 | (3) |
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6.11.1 Neighbor Hold Time |
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182 | (1) |
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6.11.2 Use of HELLO Packets |
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182 | (1) |
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6.11.3 Use of UPDATE Packets |
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183 | (1) |
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6.11.4 Use of QUERY Packets |
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183 | (1) |
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6.12 Building the EIGRP Topology Table |
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184 | (3) |
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184 | (2) |
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184 | (1) |
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185 | (1) |
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6.12.2 Use of Split Horizon and Poison Reverse |
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186 | (1) |
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6.13 Initial Neighbor and Route Discovery |
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187 | (2) |
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6.14 EIGRP Load Balancing |
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189 | (2) |
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6.15 EIGRP Route Redistribution |
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191 | (2) |
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6.16 EIGRP Route Summarization |
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193 | (1) |
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6.16.1 Auto-summarization |
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193 | (1) |
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6.16.2 Manual Summarization |
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194 | (1) |
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6.17 EIGRP Authentication |
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194 | (3) |
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6.17.1 Simple Password Authentication |
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195 | (1) |
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6.17.2 MD5 Authentication |
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195 | (2) |
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6.18 High-Level EIGRP Router Architecture, Processes, and Databases |
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197 | (9) |
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198 | (1) |
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198 | (1) |
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199 | (1) |
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6.18.4 Determining Successors and Feasible Successors |
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200 | (1) |
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6.18.5 Populating and Maintaining the Neighbor Table |
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201 | (2) |
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6.18.5.1 Understanding the SRTT, RTO, and Q Cnt Parameters |
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202 | (1) |
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6.18.6 Populating and Maintaining the Routing Table |
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203 | (1) |
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6.18.7 Handling the Loss of a Route to a Network Destination |
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204 | (1) |
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6.18.8 Handling Queries for a Route to a Network Destination |
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204 | (1) |
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6.18.9 Note on Route States, Successors, and Feasible Successors |
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205 | (1) |
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6.19 Summary of EIGRP Features |
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206 | (1) |
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207 | (1) |
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207 | (2) |
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Chapter 7 Network Path Control and Factors That Affect Routing Table Properties |
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209 | (90) |
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209 | (1) |
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7.2 Running Multiple Routing Protocols |
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209 | (3) |
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7.2.1 Running Multiple Overlapping Routing Protocols |
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210 | (1) |
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7.2.2 Running Multiple Non-Overlapping Routing Protocols |
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210 | (2) |
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7.3 The Need for Network Path Control Tools |
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212 | (7) |
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7.3.1 What Is a Routing Policy? |
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212 | (3) |
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7.3.2 Implementing Routing Policies |
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215 | (4) |
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7.3.2.1 Routing Policy Control Points |
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217 | (1) |
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7.3.2.2 Packet Filter Policy Control Points |
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218 | (1) |
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7.3.3 Routing Policies and BGP Attribute Manipulation |
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219 | (1) |
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7.4 What Is Policy-Based Routing (PBR)? |
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219 | (2) |
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221 | (5) |
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7.5.1 Using of VLSM and CIDR |
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221 | (1) |
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7.5.2 RIP Route Summarization |
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222 | (1) |
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7.5.3 EIGRP Route Summarization |
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223 | (1) |
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7.5.4 OSPF Route Summarization |
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224 | (1) |
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7.5.5 IS-IS Route Summarization |
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224 | (1) |
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7.5.6 Static Route Summarization |
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225 | (1) |
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226 | (8) |
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7.6.1 One-Point Route Redistribution |
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229 | (2) |
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7.6.2 Multipoint Route Redistribution |
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231 | (3) |
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234 | (40) |
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7.7.1 The Need for Path Control Tools |
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235 | (1) |
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7.7.2 Route Redistribution Configuration Tools |
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236 | (4) |
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7.7.2.1 Redistributing Routes into RIP |
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236 | (1) |
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7.7.2.2 Redistributing Routes into OSPF |
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237 | (1) |
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7.7.2.3 Default Metric for RIP, OSPF, or BGP |
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238 | (1) |
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7.7.2.4 Redistributing Routes into EIGRP |
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238 | (1) |
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7.7.2.5 Default Metric for EIGRP |
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239 | (1) |
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7.7.2.6 Redistributing Routes into BGP |
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239 | (1) |
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7.7.2.7 Redistributing Directly Connected Networks and Static Routes into a Routing Protocol |
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240 | (1) |
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7.7.3 Route Metric: Route Redistribution and the Seed Metric |
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240 | (3) |
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7.7.3.1 Configuring Seed Metrics |
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240 | (3) |
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7.7.4 Administrative Distance and Path Control |
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243 | (3) |
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7.7.4.1 Administrative Distance as a Path Control Tool |
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243 | (3) |
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246 | (2) |
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248 | (1) |
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249 | (3) |
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252 | (4) |
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7.7.8.1 Setting Default Routes Dynamically |
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252 | (1) |
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7.7.8.2 Setting Default Routes Statically |
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252 | (1) |
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7.7.8.3 Configuring Default Routes |
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253 | (1) |
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7.7.8.4 Generating Default Routes in RIP |
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254 | (1) |
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7.7.8.5 Generating Default Routes in EIGRP |
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254 | (1) |
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7.7.8.6 Generating Default Routes in OSPF |
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254 | (1) |
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7.7.8.7 Generating Default Routes in IS-IS |
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255 | (1) |
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7.7.8.8 Generating Default Routes in BGP |
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256 | (1) |
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256 | (5) |
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7.7.9.1 Route Map Applications |
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256 | (2) |
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7.7.9.2 Defining a Route Map |
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258 | (3) |
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261 | (2) |
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7.7.10.1 Filtering Incoming Routing Updates |
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261 | (1) |
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7.7.10.2 Filtering Outgoing Routing Updates |
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262 | (1) |
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263 | (2) |
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7.7.12 Using Policy Based Routing (PBR) for Path Control |
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265 | (2) |
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267 | (1) |
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7.7.14 IP Service Level Agreement (SLA) Probes |
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268 | (6) |
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7.7.14.1 When to Use Cisco IOS IP SLA Probes |
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269 | (1) |
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7.7.14.2 Workings of Cisco IOS IP SLA Probes |
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270 | (4) |
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7.8 Special Focus: Path Control Tools in BGP |
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274 | (16) |
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7.8.1 BGP Route Filtering and Path Attribute Manipulation |
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274 | (2) |
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7.8.1.1 Identifying BGP Routes |
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275 | (1) |
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7.8.1.2 Accepting/Rejecting BGP Routes |
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275 | (1) |
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7.8.1.3 BGP Path Attribute Manipulation |
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275 | (1) |
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7.8.2 BGP Route Filtering |
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276 | (2) |
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7.8.2.1 BGP AS-Path Filter Lists |
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276 | (1) |
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277 | (1) |
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7.8.2.3 BGP Distribute Lists |
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278 | (1) |
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278 | (1) |
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7.8.3 Injecting Routing Information into BGP |
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278 | (3) |
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7.8.3.1 Injecting Routes Statically into BGP |
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279 | (1) |
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7.8.3.2 Injecting Routes Dynamically into BGP |
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|
280 | (1) |
|
7.8.3.3 Route Injection and the BGP ORIGIN Attribute |
|
|
281 | (1) |
|
7.8.4 BGP AS-Path Prepending: AS-Path Attribute Manipulation Using Dummy Entries |
|
|
281 | (2) |
|
7.8.5 Route Aggregation in BGP |
|
|
283 | (6) |
|
7.8.5.1 Performing BGP Route Aggregation |
|
|
284 | (2) |
|
7.8.5.2 Route Aggregation without AS_SET |
|
|
286 | (1) |
|
7.8.5.3 Route Aggregation with AS_SET |
|
|
286 | (1) |
|
7.8.5.4 Changing the BGP Attributes of an Aggregate Route |
|
|
287 | (1) |
|
7.8.5.5 Advertising the Aggregate Route Only, while Suppressing the More-Specific Routes |
|
|
288 | (1) |
|
7.8.5.6 Advertising the Aggregate Route Plus All of the More-Specific Routes |
|
|
288 | (1) |
|
7.8.5.7 Advertising the Aggregate Route Plus a Subset of the More-Specific Routes |
|
|
288 | (1) |
|
7.8.6 Default Routes in BGP |
|
|
289 | (1) |
|
7.8.7 IGP Routes versus BGP Routes: Looking at Backdoors Routes |
|
|
290 | (1) |
|
7.9 Unnumbered Interfaces |
|
|
290 | (4) |
|
7.9.1 Conserving IP Addresses with Unnumbered Interfaces |
|
|
290 | (2) |
|
7.9.2 Configuring IP Unnumbered Interfaces |
|
|
292 | (1) |
|
7.9.3 Limitations of IP Unnumbered Interfaces |
|
|
293 | (1) |
|
7.9.4 Receiving Routing Updates over IP Unnumbered Interfaces |
|
|
293 | (1) |
|
7.9.5 Forwarding IP Packets over IP Unnumbered Interfaces |
|
|
294 | (1) |
|
7.10 Routing Protocol Timers |
|
|
294 | (2) |
|
|
296 | (1) |
|
|
296 | (3) |
|
|
299 | |
IP Routing Protocols: Link-State and Path-Vector Routing Protocols |
|
|
|
xvii | |
|
|
xxi | |
|
Chapter 1 Open Shortest Path Routing (OSPF) Protocol |
|
|
1 | (124) |
|
|
1 | (1) |
|
|
1 | (1) |
|
|
2 | (3) |
|
1.4 OSPF Areas and Hierarchical Routing |
|
|
5 | (12) |
|
|
7 | (1) |
|
1.4.2 Stub Area, Not-So-Stubby Area and Totally Stubby Area |
|
|
8 | (9) |
|
|
9 | (4) |
|
1.4.2.2 Totally Stubby Area |
|
|
13 | (1) |
|
1.4.2.3 Not-So-Stubby Area (NSSA) |
|
|
14 | (2) |
|
|
16 | (1) |
|
|
17 | (1) |
|
|
17 | (3) |
|
|
18 | (1) |
|
1.5.2 Area Border Router (ABR) |
|
|
18 | (1) |
|
|
19 | (1) |
|
1.5.4 Autonomous System Boundary Router (ASBR) |
|
|
19 | (1) |
|
|
20 | (30) |
|
1.6.1 Well-Known OSPF IPv4 Addresses |
|
|
21 | (1) |
|
|
22 | (4) |
|
1.6.2.1 Communicating Key Parameters |
|
|
23 | (1) |
|
1.6.2.2 The Network Mask Field |
|
|
23 | (1) |
|
1.6.2.3 The Neighbor Field |
|
|
23 | (1) |
|
1.6.2.4 The Hello Interval and Router Dead Interval Fields |
|
|
23 | (1) |
|
1.6.2.5 The Options Field |
|
|
24 | (1) |
|
1.6.2.6 The Router Priority, Designated Router, and Backup Designated Router Fields |
|
|
24 | (1) |
|
1.6.2.7 Sending Hello Packets on Broadcast and Non-Broadcast Network Segments |
|
|
25 | (1) |
|
1.6.3 OSPF Database Description Packet |
|
|
26 | (5) |
|
1.6.3.1 Rationale Behind the Use of Database Description Packets |
|
|
26 | (2) |
|
1.6.3.2 Database Exchange Process and the Master/Slave Relationship |
|
|
28 | (2) |
|
1.6.3.3 The Options Field |
|
|
30 | (1) |
|
1.6.3.4 The Interface MTU Field |
|
|
30 | (1) |
|
1.6.4 OSPF Link-State Request Packet |
|
|
31 | (1) |
|
1.6.5 OSPF Link-State Update Packet |
|
|
32 | (1) |
|
1.6.6 OSPF Link-State Acknowledgment Packet |
|
|
33 | (2) |
|
|
35 | (15) |
|
1.6.7.1 Type 1 LSA: Router-LSA |
|
|
39 | (1) |
|
1.6.7.2 Type 2 LSA: Network-LSA |
|
|
40 | (2) |
|
1.6.7.3 Type 3 LSA: Summary-LSA |
|
|
42 | (3) |
|
1.6.7.4 Type 4 LSA: ASBR-Summary-LSA |
|
|
45 | (1) |
|
1.6.7.5 Type 5 LSA: AS-External-LSA |
|
|
46 | (2) |
|
1.6.7.6 Type 7 LSA: Not-So-Stubby Area LSA |
|
|
48 | (1) |
|
|
49 | (1) |
|
1.7 Sending and Receiving LSAs |
|
|
50 | (10) |
|
1.7.1 Originating OSPF LSAs |
|
|
50 | (1) |
|
1.7.2 The LSA Flooding Procedure |
|
|
51 | (4) |
|
1.7.2.1 First Part of the LSA Flooding Process |
|
|
51 | (3) |
|
1.7.2.2 Second Part of the LSA Flooding Process |
|
|
54 | (1) |
|
1.7.3 Determining Which LSA Is More Recent |
|
|
55 | (1) |
|
1.7.4 When a Router Receives LSAs It Has Originated |
|
|
56 | (1) |
|
1.7.5 Retransmitting LSAs and the Use of Link-State Retransmission Lists |
|
|
57 | (1) |
|
1.7.6 Installing LSAs in the LSDB |
|
|
57 | (2) |
|
|
59 | (1) |
|
1.7.8 Premature Aging of LSAs |
|
|
59 | (1) |
|
1.8 OSPF Router Identifier |
|
|
60 | (2) |
|
|
62 | (3) |
|
1.9.1 Point-to-Point (P2P) |
|
|
62 | (1) |
|
|
63 | (1) |
|
1.9.3 Non-Broadcast Multiple Access (NBMA) |
|
|
63 | (1) |
|
1.9.4 Point-to-Multipoint (P2MP) |
|
|
64 | (1) |
|
1.10 OSPF Packet Processing |
|
|
65 | (4) |
|
1.10.1 Sending OSPF Packets |
|
|
65 | (1) |
|
1.10.2 Receiving OSPF Packets |
|
|
66 | (3) |
|
1.11 Neighbor Discovery and Maintenance |
|
|
69 | (10) |
|
1.11.1 OSPF Neighbor States |
|
|
69 | (3) |
|
1.11.2 OSPF Neighbor Adjacency Formation |
|
|
72 | (2) |
|
1.11.3 Formation of OSPF Adjacencies on Broadcast Multiaccess Networks |
|
|
74 | (2) |
|
1.11.4 Election of the Designated Router (DR) and Backup Designated Router (BDR) |
|
|
76 | (1) |
|
1.11.5 OSPF Adjacencies on Non-Broadcast Multiple Access (NBMA) Networks |
|
|
77 | (2) |
|
1.12 OSPF Link-State Database Synchronization |
|
|
79 | (2) |
|
1.13 LSDB Synchronization on Multiaccess Networks |
|
|
81 | (1) |
|
1.14 Advertising LSDB Changes and OSPF "Paranoid" Updates |
|
|
82 | (1) |
|
1.15 OSPF Shortest Path Computations and the IP Routing Table |
|
|
83 | (2) |
|
1.16 OSPF Routing Metrics |
|
|
85 | (4) |
|
1.16.1 OSPF Metric Types and Routes |
|
|
86 | (1) |
|
1.16.2 OSPF Cost Calculation |
|
|
87 | (1) |
|
1.16.3 Cost of Intra-Area Routes |
|
|
88 | (1) |
|
1.16.4 Cost of Inter-Area Routes |
|
|
88 | (1) |
|
1.16.5 Cost of a Default Route in an OSPF Stub Area |
|
|
89 | (1) |
|
1.17 OSPF Route Summarization |
|
|
89 | (3) |
|
1.17.1 Benefits of OSPF Route Summarization |
|
|
89 | (2) |
|
1.17.2 Types of OSPF Route Summarization |
|
|
91 | (1) |
|
|
92 | (2) |
|
1.18.1 Connecting a Non-Backbone Area to the Backbone Area through a Virtual Link |
|
|
93 | (1) |
|
1.18.2 Interconnecting a Split Backbone through a Virtual Link |
|
|
94 | (1) |
|
|
94 | (6) |
|
1.19.1 Null Authentication |
|
|
95 | (1) |
|
1.19.1.1 Generating Null Authentication Messages |
|
|
95 | (1) |
|
1.19.1.2 Verifying Null Authentication Messages |
|
|
95 | (1) |
|
1.19.2 Simple Password Authentication |
|
|
96 | (1) |
|
1.19.2.1 Generating Simple Password Authentication Messages |
|
|
96 | (1) |
|
1.19.2.2 Verifying Simple Password Authentication Messages |
|
|
97 | (1) |
|
1.19.3 Cryptographic Authentication |
|
|
97 | (3) |
|
1.19.3.1 Generating Cryptographic Authentication Messages |
|
|
99 | (1) |
|
1.19.3.2 Verifying Cryptographic Authentication Messages |
|
|
99 | (1) |
|
1.20 OSPF Protocol Data Structures and Parameters |
|
|
100 | (9) |
|
|
100 | (1) |
|
1.20.2 Area Data Structure and Parameters |
|
|
101 | (1) |
|
1.20.3 Interface Data Structure and Parameters |
|
|
102 | (1) |
|
1.20.4 Neighbor Data Structure and Parameters |
|
|
102 | (1) |
|
1.20.5 List of External Routes |
|
|
103 | (1) |
|
1.20.6 Virtual Link Parameters |
|
|
103 | (2) |
|
1.20.7 NBMA Network Parameters |
|
|
105 | (1) |
|
1.20.8 Point-to-MultiPoint (P2MP) Network Parameters |
|
|
105 | (1) |
|
1.20.9 Host Route Parameters |
|
|
106 | (1) |
|
1.20.10 The Routing Table Structure |
|
|
106 | (3) |
|
1.21 High-Level OSPF Router Architecture, Processes, and Databases |
|
|
109 | (10) |
|
|
109 | (3) |
|
1.21.2 The Routing Table Manager Process |
|
|
112 | (1) |
|
1.21.3 Understanding the Link-State Routing Process |
|
|
112 | (3) |
|
1.21.3.1 Link and Link-State |
|
|
113 | (1) |
|
1.21.3.2 Exchange of Hello Packets and Neighbor Discovery |
|
|
113 | (1) |
|
1.21.3.3 Building the Link-State Advertisements |
|
|
113 | (1) |
|
1.21.3.4 Flooding the LSAs |
|
|
114 | (1) |
|
1.21.3.5 Building the Link-State Database |
|
|
114 | (1) |
|
1.21.3.6 Building the Shortest Path Tree (SPT) |
|
|
115 | (1) |
|
1.21.3.7 Adding OSPF Best Routes to the Routing Table |
|
|
115 | (1) |
|
1.21.4 The CSPF Calculator Process |
|
|
115 | (14) |
|
1.21.4.1 Traffic Engineering Protocols |
|
|
116 | (1) |
|
1.21.4.2 Traffic Engineering Database (TED) |
|
|
117 | (1) |
|
1.21.4.3 Constrained Shortest Path First (CSPF) |
|
|
117 | (2) |
|
1.22 Summary of OSPF Features |
|
|
119 | (2) |
|
|
121 | (1) |
|
|
122 | (3) |
|
Chapter 2 Intermediate System-to-Intermediate System (IS-IS) Protocol |
|
|
125 | (140) |
|
|
125 | (1) |
|
|
125 | (2) |
|
2.3 Basic OSI Terminology and OSI Network Layer Protocols |
|
|
127 | (2) |
|
2.4 OSI Routing Hierarchies |
|
|
129 | (3) |
|
|
129 | (2) |
|
|
129 | (1) |
|
|
130 | (1) |
|
|
130 | (1) |
|
|
130 | (1) |
|
2.4.2 OSI Intradomain Routing |
|
|
131 | (1) |
|
2.5 IS-IS Hierarchical Routing |
|
|
132 | (9) |
|
2.5.1 What Is Integrated IS-IS? |
|
|
133 | (1) |
|
|
133 | (2) |
|
|
135 | (1) |
|
|
136 | (1) |
|
2.5.5 Level 1/Level 2 (or Level 1-2) Router |
|
|
137 | (1) |
|
2.5.6 Characteristics of IS-IS Areas |
|
|
138 | (1) |
|
2.5.7 OSPF Areas Versus IS-IS Areas |
|
|
138 | (3) |
|
|
141 | (6) |
|
2.6.1 NSAP Addressing Format |
|
|
141 | (1) |
|
2.6.2 Initial Domain Part (IDP) and Domain Specific Part (DSP) |
|
|
142 | (1) |
|
2.6.3 NSEL Field in NSAP Addressing |
|
|
143 | (2) |
|
2.6.4 System Identification in IS-IS |
|
|
145 | (2) |
|
2.7 IS-IS Routing Metrics |
|
|
147 | (3) |
|
2.7.1 Original IS-IS Metrics |
|
|
148 | (1) |
|
2.7.2 Extended or Wide Metrics |
|
|
149 | (1) |
|
2.7.3 Maintaining Per-Metric LSDBs in an IS-IS Router |
|
|
149 | (1) |
|
|
150 | (26) |
|
|
152 | (9) |
|
2.8.1.1 IS-IS Router Manual Area Addresses |
|
|
155 | (1) |
|
2.8.1.2 Variable-Length Fields in IS-IS Hello PDUs |
|
|
156 | (2) |
|
2.8.1.3 IS-IS Hello Messages and Adjacency Formations |
|
|
158 | (1) |
|
2.8.1.4 OSI End System and Intermediate System Hello Messages |
|
|
159 | (1) |
|
2.8.1.5 IS-IS Hello PDUs Related Timers and Parameters |
|
|
160 | (1) |
|
2.8.2 IS-IS Link-State PDUs |
|
|
161 | (12) |
|
2.8.2.1 The Remaining Lifetime Field |
|
|
163 | (1) |
|
|
164 | (1) |
|
2.8.2.3 The Sequence Number Field |
|
|
165 | (1) |
|
2.8.2.4 The LSP Checksum Field |
|
|
166 | (1) |
|
2.8.2.5 The LSP Database Overload (LSPDBOL) Bit |
|
|
167 | (1) |
|
2.8.2.6 Variable-Length Fields in IS-IS Link-State PDUs |
|
|
167 | (4) |
|
2.8.2.7 LSP Related Timers and Parameters |
|
|
171 | (2) |
|
2.8.3 IS-IS Complete Sequence Numbers PDUs |
|
|
173 | (2) |
|
2.8.3.1 Variable-Length Fields in IS-IS Sequence Numbers PDUs |
|
|
174 | (1) |
|
2.8.3.2 CSNP Related Timers and Parameters |
|
|
175 | (1) |
|
2.8.4 IS-IS Partial Sequence Numbers PDUs |
|
|
175 | (1) |
|
2.8.4.1 PSNP Related Timers and Parameters |
|
|
176 | (1) |
|
2.9 Network Types and Adjacencies |
|
|
176 | (9) |
|
2.9.1 IS-IS Adjacency Formation |
|
|
176 | (3) |
|
2.9.2 Three-way Handshake for Forming IS-IS LAN Adjacencies |
|
|
179 | (2) |
|
2.9.3 Three-way Handshake for Forming IS-IS Point-to-Point Adjacencies |
|
|
181 | (3) |
|
2.9.3.1 Original IS-IS Point-to-Point Adjacency Formation Process |
|
|
181 | (1) |
|
2.9.3.2 Extensions for Reliable IS-IS Point-to-Point Adjacency Formation |
|
|
182 | (2) |
|
|
184 | (1) |
|
2.10 Designated Intermediate System (DIS) and Pseudonodes |
|
|
185 | (6) |
|
2.10.1 IS-IS Pseudonode Concept |
|
|
185 | (1) |
|
2.10.2 Functions of the DIS |
|
|
186 | (2) |
|
2.10.3 Election of the DIS |
|
|
188 | (3) |
|
2.10.3.1 IS-IS DIS Election |
|
|
189 | (1) |
|
2.10.3.2 OSPF Designated Router (DR) and Backup DR (BDR) Election |
|
|
190 | (1) |
|
2.11 Handling IP Routing with Integrated IS-IS |
|
|
191 | (17) |
|
2.11.1 Routing Characteristics of Integrated IS-IS |
|
|
191 | (2) |
|
|
191 | (1) |
|
2.11.1.2 Routing Domain Types |
|
|
192 | (1) |
|
2.11.1.3 Area Types in a Dual Routing Domain |
|
|
192 | (1) |
|
2.11.2 Area and Domain Requirements and Restrictions |
|
|
193 | (1) |
|
2.11.3 Level 1 and Level 2 IP Routing |
|
|
194 | (1) |
|
2.11.4 Integrated IS-IS TLV Extensions |
|
|
194 | (5) |
|
2.11.4.1 IP-Specific TLVs in LAN and Point-to-Point IS-IS Hello PDUs |
|
|
195 | (1) |
|
2.11.4.2 IP-Specific TLVs in ISO 9542 IS Hello PDUs |
|
|
196 | (1) |
|
2.11.4.3 IP-Specific TLVs in LSPs |
|
|
196 | (3) |
|
2.11.4.4 IP-Specific TLVs in Sequence Number PDUs |
|
|
199 | (1) |
|
2.11.5 Addressing Routers in IS-IS PDUs |
|
|
199 | (1) |
|
2.11.6 Routing Based on IS-IS Routing Metric Type |
|
|
200 | (1) |
|
2.11.7 Route Preference Order and the SPF Algorithm Computation |
|
|
200 | (4) |
|
2.11.7.1 Level 1 Routing Order of Route Preference |
|
|
201 | (1) |
|
2.11.7.2 Level 2 Routing Order of Route Preference |
|
|
202 | (2) |
|
2.11.8 Multiaccess Broadcast LANs, Designated Intermediate System, and Pseudonode |
|
|
204 | (1) |
|
2.11.9 Maintaining Router Adjacencies in Integrated IS-IS |
|
|
204 | (1) |
|
2.11.10 Route Summarization in Integrated IS-IS |
|
|
205 | (2) |
|
2.11.11 Route Redistribution in Integrated IS-IS |
|
|
207 | (1) |
|
2.12 Extensions for Domain-Wide IP Prefix Distribution with Integrated IS-IS |
|
|
208 | (2) |
|
2.13 Newer IS-IS TLV Extensions |
|
|
210 | (16) |
|
2.13.1 IS-IS Traffic Engineering and MPLS TLVs |
|
|
210 | (5) |
|
2.13.1.1 The Extended IS Reachability TLV (Code 22) |
|
|
210 | (2) |
|
2.13.1.2 The Extended IP Reachability TLV (Code 135) |
|
|
212 | (1) |
|
2.13.1.3 The Traffic Engineering Router ID TLV (Code 134) |
|
|
213 | (1) |
|
2.13.1.4 Shared Risk Link Group TLV (Code 138) |
|
|
213 | (2) |
|
2.13.2 IS-IS Dynamic Hostname TLV |
|
|
215 | (1) |
|
2.13.3 IPv6-Specific IS-IS TLVs |
|
|
216 | (2) |
|
2.13.3.1 IPv6 Reachability TLV (Code 236) |
|
|
216 | (1) |
|
2.13.3.2 IPv6 Interface Address TLV (Code 232) |
|
|
217 | (1) |
|
2.13.3.3 IPv6 Network Layer Protocol ID (NLPID) |
|
|
217 | (1) |
|
2.13.4 Multi-Topology IS-IS TLVs |
|
|
218 | (8) |
|
2.13.4.1 Single-Topology IS-IS Support for IPv6 |
|
|
218 | (1) |
|
2.13.4.2 Multi-Topology IS-IS Support for IPv6 |
|
|
219 | (1) |
|
2.13.4.3 TLVs for Multi-Topology IS-IS |
|
|
219 | (3) |
|
2.13.4.4 Multi-Topology Adjacencies |
|
|
222 | (1) |
|
2.13.4.5 Advertising MT Reachable Intermediate Systems in LSPs |
|
|
223 | (1) |
|
2.13.4.6 Multi-Topologies and Overload, Partition, and Attached Bits |
|
|
223 | (1) |
|
2.13.4.7 Multi-Topology SPF Computation |
|
|
224 | (1) |
|
2.13.4.8 IP Forwarding Considerations in Multi-Topology IS-IS |
|
|
224 | (1) |
|
2.13.4.9 Multi-Topology Network Management Considerations |
|
|
225 | (1) |
|
2.13.5 IS-IS Router Capability TLV |
|
|
226 | (1) |
|
2.14 IS-IS Link-State Database Synchronization |
|
|
226 | (6) |
|
2.14.1 IS-IS Reliable Flooding |
|
|
227 | (1) |
|
2.14.2 LSDB Update Process |
|
|
227 | (4) |
|
2.14.2.1 LSDB Update Process on Multiaccess Broadcast Network Segments |
|
|
228 | (1) |
|
2.14.2.2 LSDB Update Process on Point-to-Points Links |
|
|
229 | (2) |
|
|
231 | (1) |
|
2.14.3.1 Handling Newer LSPs |
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231 | (1) |
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2.14.3.2 Handling Older LSPs |
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232 | (1) |
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2.14.3.3 Handling Duplicate LSPs |
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232 | (1) |
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2.15 Shortest-Path First and the Link-State Database |
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232 | (3) |
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2.15.1 SPF Algorithm Highlights |
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234 | (1) |
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2.16 OSI Routing and Suboptimal Inter-Area Routing |
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235 | (6) |
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2.16.1 IS-IS Suboptimal Inter-Area Routing |
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236 | (2) |
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2.16.2 Avoiding Suboptimal Routing using IS-IS Route Leaking |
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238 | (1) |
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2.16.3 Configuring Default Routes using the "default information originate" Command |
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239 | (1) |
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2.16.4 Other Drivers for IS-IS Route Leaking |
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240 | (1) |
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2.16.5 Some Pitfalls of IS-IS Route Leaking |
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241 | (1) |
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2.17 IS-IS Authentication |
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241 | (8) |
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2.17.1 IS-IS Simple Password Authentication |
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242 | (2) |
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2.17.1.1 Interface Password |
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243 | (1) |
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2.17.1.2 LSP Authentication (Area- or Domain-Wide) |
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243 | (1) |
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2.17.1.3 Limitations of Simple Password Authentication |
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244 | (1) |
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2.17.2 IS-IS HMAC-MD5 Cryptographic Authentication |
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244 | (1) |
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2.17.3 IS-IS Generic Authentication |
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245 | (4) |
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2.17.3.1 Authentication TLV and IS-IS Security Association |
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245 | (2) |
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2.17.3.2 Authentication Process |
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247 | (2) |
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2.18 Subnetwork Independent Functions of an IS-IS Router and Data Flow |
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249 | (3) |
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249 | (1) |
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250 | (1) |
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251 | (1) |
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2.18.4 Forwarding Process |
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252 | (1) |
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2.19 High-Level IS-IS Router Architecture, Processes, and Databases |
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252 | (8) |
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2.19.1 IS-IS Protocol Process |
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253 | (1) |
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2.19.2 IS-IS Subnetwork Dependent Process |
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254 | (1) |
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2.19.3 IS-IS Router Databases |
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255 | (1) |
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2.19.4 Routing Table Manager |
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256 | (1) |
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2.19.5 The IP Routing Table |
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256 | (1) |
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2.19.6 IS-IS Traffic Engineering |
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257 | (10) |
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2.19.6.1 Path Computation and Selection |
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257 | (1) |
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2.19.6.2 CSPF Calculator Process |
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258 | (1) |
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2.19.6.3 Signaling and Distributing MPLS Labels |
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258 | (2) |
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2.20 Summary of IS-IS Features |
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260 | (1) |
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260 | (2) |
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262 | (3) |
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Chapter 3 Border Gateway Protocol (BGP) |
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265 | (152) |
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265 | (1) |
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3.2 Interior versus Exterior Routing |
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266 | (1) |
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267 | (5) |
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3.3.1 Stub Autonomous System |
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268 | (1) |
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3.3.2 Multihomed Autonomous System |
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269 | (1) |
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3.3.3 Using BGP to Provide Transit Connectivity within an Autonomous System |
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270 | (2) |
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272 | (8) |
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3.4.1 Internal and External Peering |
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272 | (2) |
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3.4.2 Interaction Between IGPs and BGP |
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274 | (2) |
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3.4.3 BGP Peering over Physical versus Logical Connections and Multihop eBGP |
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|
276 | (1) |
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3.4.4 BGP Peering Using IP Loopback Addresses |
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277 | (2) |
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279 | (1) |
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280 | (17) |
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280 | (3) |
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283 | (6) |
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3.5.2.1 Using the BGP UPDATE Message |
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283 | (2) |
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3.5.2.2 Withdrawn Route Field and Handling BGP Route Withdrawals |
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285 | (1) |
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3.5.2.3 UPDATE Message Path Attribute Field |
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286 | (1) |
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3.5.2.4 Network Layer Reachability Information (NLRI) Field |
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287 | (1) |
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3.5.2.5 Frequency of UPDATE Messages |
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288 | (1) |
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3.5.3 BGP NOTIFICATION Message |
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289 | (6) |
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3.5.3.1 Handling Message Header Error |
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291 | (1) |
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3.5.3.2 Handling OPEN Message Error |
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291 | (1) |
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3.5.3.3 Handling UPDATE Message Error |
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292 | (1) |
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3.5.3.4 Handling NOTIFICATION Message Error |
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293 | (1) |
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3.5.3.5 Handling Hold Timer Expired Error |
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294 | (1) |
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3.5.3.6 Handling BGP Finite State Machine Error |
|
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294 | (1) |
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3.5.3.7 Sending the Error Code Cease |
|
|
294 | (1) |
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3.5.3.8 BGP Connection Collision Detection |
|
|
294 | (1) |
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3.5.4 BGP KEEPALIVE Message |
|
|
295 | (1) |
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3.5.5 BGP ROUTE-REFRESH Message |
|
|
296 | (1) |
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3.6 BGP Session States and Finite State Machine |
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|
297 | (19) |
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299 | (1) |
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300 | (4) |
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304 | (3) |
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307 | (3) |
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310 | (3) |
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313 | (3) |
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3.7 BGP Version Negotiation |
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316 | (1) |
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316 | (24) |
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3.8.1 Categories of BGP Path Attributes |
|
|
317 | (2) |
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3.8.1.1 Handling Unrecognized Optional BGP Path Attributes |
|
|
318 | (1) |
|
3.8.2 Origin Attribute (ORIGIN) |
|
|
319 | (1) |
|
3.8.3 AS-Path Attribute (AS_PATH) |
|
|
319 | (3) |
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3.8.3.1 Using the AS-Path Attribute |
|
|
320 | (1) |
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3.8.3.2 Originating a BGP Route |
|
|
321 | (1) |
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3.8.3.3 Propagating a BGP Route |
|
|
321 | (1) |
|
3.8.4 Next-Hop Attribute (NEXT_HOP) |
|
|
322 | (4) |
|
3.8.4.1 Advertising a Route to an Internal BGP Peer |
|
|
322 | (2) |
|
3.8.4.2 Advertising a Route to an External BGP Peer One Hop Away |
|
|
324 | (1) |
|
3.8.4.3 Advertising a Route to an External BGP Peer Multiple Hops Away |
|
|
325 | (1) |
|
3.8.4.4 Other Rules Governing the Advertisement of a Route |
|
|
326 | (1) |
|
3.8.5 Multiple Exit Discriminator (MED) Attribute (MULTI_EXIT_DISC) |
|
|
326 | (2) |
|
3.8.6 Local Preference Attribute (LOCAL_PREF) |
|
|
328 | (2) |
|
3.8.7 Communities Attribute (COMMUNITIES) |
|
|
330 | (7) |
|
3.8.7.1 BGP Communities Attribute |
|
|
330 | (3) |
|
3.8.7.2 BGP Extended Communities Attribute |
|
|
333 | (4) |
|
3.8.8 Atomic Aggregate Attribute (ATOMIC_ AGGREGATE) |
|
|
337 | (1) |
|
3.8.9 Aggregator Attribute (AGGREGATOR) |
|
|
338 | (1) |
|
3.8.10 Weight Attribute (WEIGHT) |
|
|
339 | (1) |
|
3.9 Understanding the iBGP Full Mesh Requirement |
|
|
340 | (1) |
|
3.10 Autonomous System Numbers (ASNs) |
|
|
341 | (3) |
|
3.10.1 Original 16-bit ASN Space |
|
|
341 | (1) |
|
3.10.2 Newer 32-Bit ASN Space |
|
|
342 | (2) |
|
3.10.2.1 Extensions for Carrying 32-bit ASNs in BGP |
|
|
342 | (2) |
|
3.11 BGP Path Attributes and Route Aggregation |
|
|
344 | (2) |
|
3.11.1 Route Aggregation Rules |
|
|
344 | (1) |
|
3.11.2 AS_PATH Attribute and Route Aggregation |
|
|
345 | (1) |
|
3.12 Considering IGP Cost When Deciding the Best Exit Point of an Autonomous System |
|
|
346 | (1) |
|
3.13 Understanding the Role of the BGP Routing Table and IP Routing Table in BGP |
|
|
347 | (1) |
|
3.14 Alternatives to the iBGP Full Mesh Requirement |
|
|
348 | (2) |
|
|
350 | (6) |
|
3.15.1 Rationale Behind BGP Confederations |
|
|
350 | (2) |
|
3.15.2 BGP Confederation Parameters |
|
|
352 | (2) |
|
|
354 | (1) |
|
3.15.4 AS_PATH Modification Rules |
|
|
354 | (2) |
|
3.15.4.1 Originating a BGP Route |
|
|
354 | (1) |
|
3.15.4.2 Propagating a BGP Route |
|
|
355 | (1) |
|
3.16 BGP Route Reflection |
|
|
356 | (9) |
|
3.16.1 Concept of Route Reflection |
|
|
356 | (3) |
|
3.16.2 Route Reflection with Redundancy |
|
|
359 | (1) |
|
3.16.3 Preventing Routing Information Loops During Route Reflection |
|
|
360 | (1) |
|
3.16.4 Route Reflection with Multiple Clusters |
|
|
361 | (4) |
|
|
365 | (4) |
|
3.17.1 BGP Route Server Behaviors |
|
|
367 | (2) |
|
3.17.1.1 BGP Attribute Transparency |
|
|
368 | (1) |
|
3.17.1.2 NEXT_HOP Attribute |
|
|
368 | (1) |
|
3.17.1.3 AS_PATH Attribute |
|
|
368 | (1) |
|
3.17.1.4 MED (MULTI_EXIT_DISC) Attribute |
|
|
368 | (1) |
|
3.17.1.5 BGP Communities Attributes |
|
|
369 | (1) |
|
3.18 BGP Best Path Selection Process |
|
|
369 | (11) |
|
3.18.1 Phase 1: Calculating the Degree of Route Preference |
|
|
370 | (1) |
|
3.18.2 Phase 2: Best Path Selection |
|
|
371 | (7) |
|
3.18.2.1 BGP Route Resolvability Condition |
|
|
372 | (1) |
|
3.18.2.2 A Note on BGP Recursive Route Lookup |
|
|
373 | (1) |
|
3.18.2.3 Deep Dive into BGP Recursive Lookup |
|
|
374 | (2) |
|
3.18.2.4 BGP Best Path Selection Algorithm (with Tie Breakers) |
|
|
376 | (2) |
|
3.18.3 Phase 3: BGP Route Dissemination |
|
|
378 | (2) |
|
3.18.3.1 BGP Update-Send Process |
|
|
379 | (1) |
|
3.18.3.2 Originating BGP Routes |
|
|
379 | (1) |
|
3.19 BGP Session Security |
|
|
380 | (10) |
|
3.19.1 TCP MD5 Signature Option |
|
|
380 | (1) |
|
3.19.2 TCP Authentication Option (TCP-AO) |
|
|
381 | (9) |
|
3.19.2.1 Format of the TCP Authentication Option |
|
|
382 | (1) |
|
3.19.2.2 TCP-AO Keys and Their Properties |
|
|
383 | (2) |
|
3.19.2.3 Per-Connection TCP-AO Parameters |
|
|
385 | (1) |
|
3.19.2.4 Cryptographic Algorithms |
|
|
386 | (2) |
|
3.19.2.5 Sending TCP Segments with TCP-AO |
|
|
388 | (1) |
|
3.19.2.6 Receiving TCP Segments with TCP-AO |
|
|
389 | (1) |
|
3.20 Factors Affecting BGP Device and Network Convergence |
|
|
390 | (5) |
|
3.20.1 Number of BGP Peers |
|
|
390 | (1) |
|
3.20.2 Number of Routes per BGP Peer |
|
|
391 | (1) |
|
3.20.3 Routing Policy Processing/Reconfiguration |
|
|
391 | (1) |
|
3.20.4 Interactions with Other Routing Protocols |
|
|
391 | (1) |
|
3.20.5 BGP Route Flap Damping |
|
|
391 | (2) |
|
3.20.6 Handling BGP Control Plane Traffic |
|
|
393 | (1) |
|
3.20.7 Handling BGP Data Plane Traffic |
|
|
394 | (1) |
|
|
394 | (1) |
|
3.20.9 BGP Authentication |
|
|
394 | (1) |
|
3.21 High-Level BGP Router Architecture, Processes, and Databases |
|
|
395 | (10) |
|
3.21.1 BGP RIB Manager Process |
|
|
396 | (5) |
|
3.21.2 Neighbor Manager Process |
|
|
401 | (1) |
|
3.21.3 Policy Manager Process |
|
|
401 | (2) |
|
3.21.3.1 Input Policy Engine |
|
|
402 | (1) |
|
3.21.3.2 Output Policy Engine |
|
|
402 | (1) |
|
3.21.4 Routing Table Manager Process |
|
|
403 | (1) |
|
3.21.5 BGP Sessions and Operational Events |
|
|
403 | (1) |
|
3.21.6 Processing of BGP UPDATE Messages: Sending and Receiving |
|
|
404 | (1) |
|
3.22 BGP Link-State Distribution |
|
|
405 | (5) |
|
3.22.1 Need for Link-State Distribution and Traffic Engineering Across Internetworks |
|
|
406 | (1) |
|
3.22.2 Example Deployment Scenario of BGP-LS |
|
|
407 | (1) |
|
3.22.3 Example Link-State Distribution Architecture |
|
|
408 | (2) |
|
3.23 Summary of BGP Features |
|
|
410 | (1) |
|
|
411 | (1) |
|
|
412 | (5) |
|
|
417 | |