OSPF and IS-IS
Choosing an IGP for Large-Scale Networks: Choosing an IGP for Large-Scale Networks
Published on 10. November 2005
Book
Paperback/Softback
480 pages
978-0-321-16879-5 (ISBN)
Description
The practical guide to large-scale networking with OSPF and IS-IS This is the definitive guide to using OSPF and IS-IS protocols in large-scale IP enterprise, carrier, and service provider networks. Well-known network designer Jeff Doyle draws on his consulting experience, offering realistic advice and straight answers on every aspect of working with link-state protocols--from scalability, reliability, and security to area design and database synchronization. This book is organized to help network engineers and architects compare OSPF and IS-IS. One feature at a time, Doyle first demonstrates how a topic or feature is implemented in OSPF, and then walks through a similar implementation using IS-IS. Professionals who are relatively new to large-scale networking will welcome his practical introduction to the concepts, goals, and history of link state protocols.Coverage includes * Understanding message types, encapsulation, architecture, LSAs, and LSPs * Optimizing addressing, neighbor discovery, adjacencies, and router designation * Improving scalability: controlling the scope of flooding, link state database size, SPF calculation efficiency, and much more * Designing and operating large-scale networks for maximum security and reliability * Hardening networks to thwart attacks against routing protocols * Comparing OSPF and IS-IS extensibility * Utilizing extensions for MPLS-based traffic engineering, IPv6, and multi-topology routing * Troubleshooting OSPF and IS-IS log entries, debug output, and LS databases Doyle's thorough explanations, end-of-chapter review questions, and many wide-ranging examples for both Cisco's IOS and Juniper's JUNOS also make this book an exceptional resource for anyone pursuing a CCIE or JNCIE certification.
A(c) Copyright Pearson Education. All rights reserved.
A(c) Copyright Pearson Education. All rights reserved.
More details
Person
Specializing in IP routing protocols, MPLS, and IPv6, Jeff Doyle has designed or assisted in the design of large-scale IP service provider networks throughout North America, Europe, Japan, Korea, and the Peoples Republic of China. Jeff is the author of CCIE Professional Development: Routing TCP/IP, Volumes I and II, is an editor and contributing author of Juniper Networks Routers: The Complete Reference. Jeff has presented numerous corporate seminars for Juniper Networks, and has also spoken at NANOG, JANOG, APRICOT, and at IPv6 Forum conferences.
Prior to joining Juniper Networks Jeff was a Senior Network Systems Consultant with International Network Services, where he also specialized in IP routing protocol design. Jeff holds a BA from Memphis State University, and studied Electrical Engineering at the University of New Mexico. Jeff lives in Denver, Colorado with his wife and four children.
Prior to joining Juniper Networks Jeff was a Senior Network Systems Consultant with International Network Services, where he also specialized in IP routing protocol design. Jeff holds a BA from Memphis State University, and studied Electrical Engineering at the University of New Mexico. Jeff lives in Denver, Colorado with his wife and four children.
Content
About the Author.
Preface.
Audience.
What Is a Large-Scale Data Communications Network?
A Word on IOS and JUNOS.
Acknowledgments.
1. The Roots of LinkState Protocols.
An Intergalactic Network.
ARPANET.
The Network Working Group.
The Birth of the Internet.
Routing in the ARPANET.
The European Invasion.
Separate But Equal.
Conclusion.
2. LinkState Basics.
Vector Protocol Basics.
Vector Protocol Convergence.
Common Characteristics of Vector Protocols .
Routing Loops.
Fundamental Link State Concepts.
Adjacencies.
Flooding.
Announcement Headers.
Database Synchronization.
SPF Calculations.
Areas.
Review Questions.
3. Message Types.
Comparative Terminology.
Message Encapsulation.
Message Architecture.
Message Types.
LSAs and LSPs.
Subnetwork Dependent and Independent Functions.
Subnetwork Dependent Functions.
Subnetwork Independent Functions.
Review Questions.
4. Addressing, Neighbor Discovery, and Adjacencies.
Router and Area IDs.
OSPF Router IDs.
Troubleshooting: Duplicate Router IDs.
OSPF Area IDs.
IS-IS System and Area IDs.
The Hello Protocol.
OSPF Hello Protocol Basics.
IS-IS Hello Protocol Basics.
IS-IS Dynamic Hostname Exchange.
OSPF Domain Name Lookup.
Adjacencies.
OSPF Adjacencies.
IS-IS Adjacencies.
Designated Routers.
OSPF Designated Routers.
IS-IS Designated Intermediate Systems.
Media Types.
OSPF Network Types.
IS-IS Network Types.
Interface Databases.
The OSPF Interface Data Structure.
OSPF Interface States.
The IS-IS Interface Data Structure.
Review Questions.
5. Flooding.
Flooding Components.
OSPF Flooding.
IS-IS Flooding.
Areas and Router Types.
OSPF Areas and Router Types.
IS-IS Areas and Router Types.
Metric Types.
OSPF Metrics.
IS-IS Metrics.
Essential LSAs.
Router LSAs.
Network LSAs.
Network Summary LSAs.
ASBR Summary LSAs.
AS-External LSAs.
Essential TLVs.
Area Addresses TLV.
IS Neighbors TLV.
Protocols Supported TLV.
IP Interface Addresses TLV.
IP Internal Reachability Information TLV.
IP External Reachability Information TLV.
Extended IS Reachability TLV.
Extended IP Reachability TLV.
Review Questions.
6. LinkState Database Synchronization.
OSPF Database Synchronization.
OSPF Packets Used in Database Synchronization.
The Options Field.
The OSPF Neighbor Data Structure.
LSA Lists for Database Exchange and Flooding.
Database Exchange Management: Masters and Slaves.
The OSPF Neighbor State Machine.
Troubleshooting: Reading OSPF Log Entries and Debug Output.
Troubleshooting: Comparing OSPF LS Databases.
IS-IS Database Synchronization.
IS-IS PDUs Used in Synchronization.
Send Routing Message and Send Sequence Number Flags.
Synchronization on Point-to-Point Networks.
Synchronization on Broadcast Networks.
Troubleshooting: Reading IS-IS Log Entries and Debug Output.
Troubleshooting: Comparing IS-IS LS Databases.
Review Questions.
7. Area Design.
Area Scalability.
Area Reliability.
OSPF Areas.
Backbone and Non-Backbone Areas.
Factors for Scaling OSPF Areas.
External Prefixes and OSPF Scaling.
Stub Areas.
Totally Stubby Areas.
Not-So-Stubby Areas.
Address Summarization.
Virtual Links.
IS-IS Areas.
Backbone and Non-Backbone Areas.
Factors for Scaling IS-IS Areas.
Default IS-IS L1 Area Behavior.
Redundant L1/L2 Routers.
Address Summarization, Again.
L2 to L1 Route Leaking.
Redistributing External Prefixes into IS-IS.
Multiple Area IDs.
IS-IS Virtual Links.
BGP and Area Design.
Review Questions.
8. Scaling.
SPF Enhancements.
Equal-Cost Multipath.
Pseudonodes and ECMP.
Incremental SPF Calculations.
Partial Route Calculations.
SPF Delay.
Flooding Enhancements.
Transmit Pacing.
Retransmit Pacing.
Mesh Groups.
Demand Circuits and Flood Reduction.
Fragmentation.
Overloading.
Review Questions.
9. Security and Reliability.
Routing Protocol Vulnerabilities.
Malicious Threats.
Non-Malicious Threats.
Security and Reliability Features.
Inherent Security.
Authentication.
Checksums.
Graceful Restart.
Bidirectional Forwarding Detection.
Designing for Security and Reliability.
Redundancy.
Protecting the Domain Edge.
Protecting the Router.
Operating for Security and Reliability.
Configuration Management.
Change Management.
The Network Lab.
Review Questions.
10. Extensibility.
Extending OSPF.
The OSPF Extensibility Problem.
Opaque LSAs.
The Router Information Opaque LSA.
Extending IS-IS.
The IS-IS Extensibility Advantage.
The Protocols Supported TLV.
Route Tagging.
Review Questions.
11. Extensions for MPLS Traffic Engineering.
MPLS: An Overview.
Labels and Label Switching.
Forwarding Equivalence Classes and Label Binding.
Label Distribution.
The MPLS Header.
Traffic Engineering: An Overview.
TE Link Parameters.
Constrained Shortest Path First.
OSPF Extensions for Traffic Engineering.
IS-IS Extensions for Traffic Engineering.
Review Questions.
12. Extensions for IPv6.
IPv6: An Overview.
IPv6 Features and Functions.
IPv6 Address Format.
IPv6 Address Representation.
The Neighbor Discovery Protocol.
Stateless Address Autoconfiguration.
IPv6 Header Format.
Extension Headers.
OSPFv3.
IPv4 and IPv6 Compatibility in OSPF.
Differences from OSPFv2.
OSPFv3 LSAs.
The Options Field.
OSPFv3 Packets.
Future Extensions to OSPFv3.
IS-IS Extensions for IPv6.
Review Questions.
13. Extensions for Multi-Topology Routing.
OSPF Extensions for Multi-Topology Routing.
MT-OSPF Procedures.
MT-OSPF LSAs.
Link Exclusion.
IS-IS Extensions for Multi-Topology Routing.
MT-ISIS Procedures.
MT-ISIS TLVs.
Review Questions.
AFTERWORD: The Future of LinkState Protocols.
Index.
Preface.
Audience.
What Is a Large-Scale Data Communications Network?
A Word on IOS and JUNOS.
Acknowledgments.
1. The Roots of LinkState Protocols.
An Intergalactic Network.
ARPANET.
The Network Working Group.
The Birth of the Internet.
Routing in the ARPANET.
The European Invasion.
Separate But Equal.
Conclusion.
2. LinkState Basics.
Vector Protocol Basics.
Vector Protocol Convergence.
Common Characteristics of Vector Protocols .
Routing Loops.
Fundamental Link State Concepts.
Adjacencies.
Flooding.
Announcement Headers.
Database Synchronization.
SPF Calculations.
Areas.
Review Questions.
3. Message Types.
Comparative Terminology.
Message Encapsulation.
Message Architecture.
Message Types.
LSAs and LSPs.
Subnetwork Dependent and Independent Functions.
Subnetwork Dependent Functions.
Subnetwork Independent Functions.
Review Questions.
4. Addressing, Neighbor Discovery, and Adjacencies.
Router and Area IDs.
OSPF Router IDs.
Troubleshooting: Duplicate Router IDs.
OSPF Area IDs.
IS-IS System and Area IDs.
The Hello Protocol.
OSPF Hello Protocol Basics.
IS-IS Hello Protocol Basics.
IS-IS Dynamic Hostname Exchange.
OSPF Domain Name Lookup.
Adjacencies.
OSPF Adjacencies.
IS-IS Adjacencies.
Designated Routers.
OSPF Designated Routers.
IS-IS Designated Intermediate Systems.
Media Types.
OSPF Network Types.
IS-IS Network Types.
Interface Databases.
The OSPF Interface Data Structure.
OSPF Interface States.
The IS-IS Interface Data Structure.
Review Questions.
5. Flooding.
Flooding Components.
OSPF Flooding.
IS-IS Flooding.
Areas and Router Types.
OSPF Areas and Router Types.
IS-IS Areas and Router Types.
Metric Types.
OSPF Metrics.
IS-IS Metrics.
Essential LSAs.
Router LSAs.
Network LSAs.
Network Summary LSAs.
ASBR Summary LSAs.
AS-External LSAs.
Essential TLVs.
Area Addresses TLV.
IS Neighbors TLV.
Protocols Supported TLV.
IP Interface Addresses TLV.
IP Internal Reachability Information TLV.
IP External Reachability Information TLV.
Extended IS Reachability TLV.
Extended IP Reachability TLV.
Review Questions.
6. LinkState Database Synchronization.
OSPF Database Synchronization.
OSPF Packets Used in Database Synchronization.
The Options Field.
The OSPF Neighbor Data Structure.
LSA Lists for Database Exchange and Flooding.
Database Exchange Management: Masters and Slaves.
The OSPF Neighbor State Machine.
Troubleshooting: Reading OSPF Log Entries and Debug Output.
Troubleshooting: Comparing OSPF LS Databases.
IS-IS Database Synchronization.
IS-IS PDUs Used in Synchronization.
Send Routing Message and Send Sequence Number Flags.
Synchronization on Point-to-Point Networks.
Synchronization on Broadcast Networks.
Troubleshooting: Reading IS-IS Log Entries and Debug Output.
Troubleshooting: Comparing IS-IS LS Databases.
Review Questions.
7. Area Design.
Area Scalability.
Area Reliability.
OSPF Areas.
Backbone and Non-Backbone Areas.
Factors for Scaling OSPF Areas.
External Prefixes and OSPF Scaling.
Stub Areas.
Totally Stubby Areas.
Not-So-Stubby Areas.
Address Summarization.
Virtual Links.
IS-IS Areas.
Backbone and Non-Backbone Areas.
Factors for Scaling IS-IS Areas.
Default IS-IS L1 Area Behavior.
Redundant L1/L2 Routers.
Address Summarization, Again.
L2 to L1 Route Leaking.
Redistributing External Prefixes into IS-IS.
Multiple Area IDs.
IS-IS Virtual Links.
BGP and Area Design.
Review Questions.
8. Scaling.
SPF Enhancements.
Equal-Cost Multipath.
Pseudonodes and ECMP.
Incremental SPF Calculations.
Partial Route Calculations.
SPF Delay.
Flooding Enhancements.
Transmit Pacing.
Retransmit Pacing.
Mesh Groups.
Demand Circuits and Flood Reduction.
Fragmentation.
Overloading.
Review Questions.
9. Security and Reliability.
Routing Protocol Vulnerabilities.
Malicious Threats.
Non-Malicious Threats.
Security and Reliability Features.
Inherent Security.
Authentication.
Checksums.
Graceful Restart.
Bidirectional Forwarding Detection.
Designing for Security and Reliability.
Redundancy.
Protecting the Domain Edge.
Protecting the Router.
Operating for Security and Reliability.
Configuration Management.
Change Management.
The Network Lab.
Review Questions.
10. Extensibility.
Extending OSPF.
The OSPF Extensibility Problem.
Opaque LSAs.
The Router Information Opaque LSA.
Extending IS-IS.
The IS-IS Extensibility Advantage.
The Protocols Supported TLV.
Route Tagging.
Review Questions.
11. Extensions for MPLS Traffic Engineering.
MPLS: An Overview.
Labels and Label Switching.
Forwarding Equivalence Classes and Label Binding.
Label Distribution.
The MPLS Header.
Traffic Engineering: An Overview.
TE Link Parameters.
Constrained Shortest Path First.
OSPF Extensions for Traffic Engineering.
IS-IS Extensions for Traffic Engineering.
Review Questions.
12. Extensions for IPv6.
IPv6: An Overview.
IPv6 Features and Functions.
IPv6 Address Format.
IPv6 Address Representation.
The Neighbor Discovery Protocol.
Stateless Address Autoconfiguration.
IPv6 Header Format.
Extension Headers.
OSPFv3.
IPv4 and IPv6 Compatibility in OSPF.
Differences from OSPFv2.
OSPFv3 LSAs.
The Options Field.
OSPFv3 Packets.
Future Extensions to OSPFv3.
IS-IS Extensions for IPv6.
Review Questions.
13. Extensions for Multi-Topology Routing.
OSPF Extensions for Multi-Topology Routing.
MT-OSPF Procedures.
MT-OSPF LSAs.
Link Exclusion.
IS-IS Extensions for Multi-Topology Routing.
MT-ISIS Procedures.
MT-ISIS TLVs.
Review Questions.
AFTERWORD: The Future of LinkState Protocols.
Index.