Network Recovery : Protection and Restoration of Optical, SONET-SDH, IP, and MPLS (The Morgan Kaufmann Series in Networking)

Network Recovery is the first book to provide detailed information on protecting and restoring communication networks, and it sets a sky-high standard for any that may follow. Inside, you'll learn specific techniques that work at each layer of the networking hierarchy-including optical, SONET-SDH, IP, and MPLS-as well as multi-layer escalation strategies that offer the highest level of protection. The authors begin with an incisive introduction to the issues that define the field of network protection and restoration, and as the book progresses they explain everything you need to know about the relevant protocols, providing theoretical analyses wherever appropriate. If you work for a network-dependent organization, large or small, you'll want to keep Network Recovery within reach at all times. * Shows you how to implement protection and recovery techniques that will save your organization time and money. * Documents techniques for the optical, SONET-SDH, IP, and MPLS layers, as well as multi-layer escalation strategies. * Shows you how to evaluate these techniques in relation to one another, so you can develop an optimal network recovery design. * Provides industry examples and simulation results. * Delves into the inner workings of relevant protocols and offers theoretical analyses wherever this information contributes to your practical knowledge. Cover......Page 1 Contents......Page 8 Foreword......Page 16 Preface......Page 18 1.1 Communications Networks Today......Page 22 1.1.1 Fundamental Networking Concepts......Page 24 1.1.2 Layered Network Representation......Page 26 1.1.3 Network Planes......Page 27 1.2 Network Reliability......Page 29 1.2.1 Definitions......Page 30 1.2.2 Which Failures Can Occur?......Page 33 1.2.3 Reliability Requirements for Various Users and Services......Page 39 1.2.4 Measures to Increase Reliability......Page 41 1.3 Different Phases in a Recovery Process......Page 43 1.3.1 Recovery Cycle......Page 44 1.3.2 Reversion Cycle......Page 45 1.4.1 Scope of Failure Coverage......Page 46 1.4.3 Backup Capacity Requirements......Page 47 1.4.8 Scalability......Page 48 1.5 Characteristics of Single-Layer Recovery Mechanisms......Page 49 1.5.1 Backup Capacity Dedicated versus Shared......Page 50 1.5.2 Recovery Paths: Preplanned versus Dynamic......Page 51 1.5.3 Protection versus Restoration......Page 52 1.5.4 Global versus Local Recovery......Page 53 1.5.5 Control of Recovery Mechanisms......Page 55 1.5.6 Ring Networks versus Mesh Networks......Page 56 1.6 Multilayer Recovery......Page 57 1.7 Conclusion......Page 59 2 SONET/SDH Networks......Page 60 2.1.1 Transmission Networks......Page 61 2.1.2 Management of (Transmission) Networks......Page 63 2.1.3 Structuring/Modeling Transmission Networks......Page 64 2.2.1 Introduction......Page 66 2.2.2 Structure of SDH Networks......Page 67 2.2.3 SDH Frame Structure: Overhead Bytes Relevant for Network Recovery......Page 69 2.2.4 SDH Network Elements......Page 73 2.2.5 Summary......Page 76 2.2.6 Differences between SONET and SDH......Page 77 2.3 Operational Aspects......Page 78 2.3.1 Fault Management Processes......Page 79 2.3.2 Fault Detection and Propagation Inside a Network Element......Page 81 2.3.3 Fault Propagation and Notification on a Network Level......Page 91 2.3.4 Automatic Protection Switching Protocol......Page 95 2.3.5 Summary......Page 101 2.4 Ring Protection......Page 102 2.4.1 Multiplex Section–Shared Protection Ring......Page 104 2.4.2 Multiplex Section–Dedicated Protection Ring......Page 112 2.4.4 Ring Interconnection......Page 114 2.4.5 Summary......Page 126 2.4.6 Differences between SONET and SDH......Page 127 2.5.1 Multiplex Section Protection......Page 128 2.5.2 Path Protection......Page 129 2.6.1 Protection versus Restoration......Page 134 2.7 Case Study......Page 136 2.8 Conclusion......Page 148 2.9 Recommended Reference Work and Research-Related Topics......Page 150 3 Optical Networks......Page 152 3.1.1 Wavelength Division Multiplexing in the Point-to-Point Optical Network Layer......Page 153 3.1.3 An Optical Network Layer Organized in Rings......Page 156 3.1.4 Meshed Optical Networks......Page 158 3.2.1 Architectural Aspects and Structure of the Optical Transport Network......Page 160 3.2.2 Structure of the Optical Transport Module......Page 163 3.3 Fault Detection and Propagation......Page 165 3.3.1 The Optical Network Overhead......Page 166 3.3.2 Defects in the Optical Transport Network......Page 173 3.3.3 OTN Maintenance Signals and Alarm Suppression......Page 175 3.4.1 Recovery at the Optical Layer?......Page 178 3.4.2 Standardization Work on Recovery in the Optical Transport Network......Page 179 3.4.3 Shared Risk Group......Page 180 3.5 Recovery Mechanisms in Ring-Based Optical Networks......Page 181 3.5.1 Multiplex Section Protection in Ring-Based Optical Networks......Page 184 3.5.2 Optical Channel Protection in Ring-Based Optical Networks......Page 187 3.5.3 OMS- versus OCh-Based Approach......Page 191 3.5.4 Shared versus Dedicated Approach......Page 192 3.6 Recovery Mechanisms in Mesh-Based Optical Networks......Page 194 3.6.1 Protection......Page 196 3.6.2 Protection in a WP Network versus Protection in a VWP Network......Page 197 3.6.3 Restoration......Page 198 3.6.4 Protection versus Restoration......Page 201 3.7 Ring-Based versus Mesh-Based Recovery Schemes......Page 203 3.8.1 Availability Calculations......Page 206 3.8.2 Availability: Some Observations......Page 213 3.9.1 p-Cycles......Page 218 3.9.2 Meta-Mesh Recovery Technique......Page 220 3.10 Conclusion......Page 221 4 IP Routing......Page 224 4.1.2 Distance Vector Routing Protocols Overview (''Bellman-Ford'')......Page 225 4.1.3 Link State Routing Protocols Overview......Page 228 4.1.4 IP Routing: A Global versus Local Restoration Mechanism?......Page 234 4.2.2 Hold-Off Timer......Page 235 4.2.4 Computation of the Routing Table......Page 236 4.2.5 An Example of IP Rerouting upon Link Failure......Page 238 4.3.1 Failure Profiles......Page 241 4.3.2 Failure Detection......Page 243 4.3.3 Failure Characterization......Page 245 4.3.4 Analysis of the Various Failure Types and Their Impact on Traffic Forwarding......Page 246 4.4 Dampening Algorithms......Page 247 4.5 FIS Propagation (LSA Origination and Flooding)......Page 250 4.5.1 LSA Origination Process......Page 252 4.5.2 LSA Flooding Process......Page 254 4.6 Route Computation......Page 258 4.6.1 Shortest Path Computation......Page 259 4.6.2 The Dijkstra Algorithm......Page 262 4.6.3 Shortest Path Computation Triggers......Page 270 4.6.4 Routing Information Base Update......Page 272 4.7 Temporary Loops during Network State Changes......Page 273 4.7.1 Temporary Loops in the Case of a Link or Node Failure......Page 274 4.7.2 Temporary Loops Caused by a Restored Network Element......Page 278 4.8 Load Balancing......Page 280 4.9.1 IP Traffic Engineering at Steady State......Page 283 4.9.2 QoS Guarantee during Failure......Page 285 4.10 Nonstop Forwarding: An Example with OSPF......Page 287 4.10.2 Mode of Operation of the Restarting Router......Page 288 4.10.4 Backward Compatibility......Page 290 4.11 A Case Study with IS-IS......Page 291 4.12 Summary......Page 299 4.13.1 Definition of Algorithm Complexity......Page 300 4.13.2 NP Complete Problem......Page 305 4.14.1 Motivation......Page 306 4.14.3 Algorithm Description......Page 308 4.15 Interaction between Fast IGP Convergence and NSF......Page 314 4.16 Research-Related Topics......Page 316 5 MPLS Traffic Engineering Recovery Mechanisms......Page 318 5.1.1 Traffic Engineering in Data Networks......Page 319 5.1.2 Terminology......Page 322 5.1.3 MPLS Traffic Engineering Components......Page 324 5.1.4 Notion of Preemption in MPLS Traffic Engineering......Page 326 5.1.5 Motivations for Deploying MPLS Traffic Engineering......Page 327 5.2.1 Fault Detection Time......Page 328 5.2.3 Fault Notification Time......Page 329 5.2.5 Traffic Recovery Time......Page 330 5.3.1 Fault Signal Indication......Page 331 5.3.2 Mode of Operation......Page 332 5.3.3 Recovery Time......Page 334 5.4 MPLS Traffic Engineering Global Path Protection......Page 335 5.4.1 Mode of Operation......Page 336 5.5.1 Terminology......Page 337 5.5.2 Principles of Local Protection Recovery Techniques......Page 338 5.5.3 Local Protection: One-to-One Backup......Page 339 5.5.4 Local Protection: ''Facility Backup''......Page 341 5.5.5 Properties of a Traffic Engineering LSP......Page 346 5.5.6 Notification of Tunnel Locally Repaired......Page 348 5.5.8 Two Strategies for Deploying MPLS Traffic Engineering for Fast Recovery......Page 350 5.6 Another MPLS Traffic Engineering Recovery Alternative......Page 354 5.7 Load Balancing......Page 355 5.8.2 Scalability......Page 357 5.8.3 Bandwidth Sharing Capability......Page 361 5.8.4 Summary......Page 364 5.9.1 MPLS Traffic Engineering Global Default Restoration......Page 367 5.9.3 MPLS Traffic Engineering Local Protection......Page 368 5.10.1 MPLS-Specific Failure Detection Hello-Based Protocols......Page 369 5.10.2 Requirements for an Accurate Failure Type Characterization......Page 370 5.10.3 Analysis of the Various Failure Types and Their Impact on Traffic Forwarding......Page 374 5.11.1 Case Study 1......Page 375 5.11.2 Case Study 2......Page 380 5.11.3 Case Study 3......Page 383 5.12 Standardization......Page 391 5.13 Summary......Page 392 5.14.1 SESSION-ATTRIBUTE Object......Page 393 5.14.2 FAST-REROUTE Object......Page 395 5.14.3 DETOUR Object......Page 396 5.14.4 Route Record Object......Page 397 5.14.6 Identification of a Signaled TE LSP......Page 399 5.14.7 Signaling with Facility Backup......Page 400 5.14.8 Signaling with One-to-One Backup......Page 403 5.14.9 Detour Merging......Page 405 5.15 Backup Path Computation......Page 406 5.15.2 Requirements for Strict QoS Guarantees during Failure......Page 407 5.15.3 Network Design Considerations......Page 408 5.15.4 Notion of Bandwidth Sharing between Backup Paths......Page 413 5.15.5 Backup Path Computation: MPLS TE Global Path Protection......Page 414 5.15.6 Backup Tunnel Path Computation: MPLS TE Fast Reroute Facility Backup......Page 418 5.15.7 Backup Tunnel Path Computation with MPLS TE Fast Reroute One-to-One Backup......Page 440 5.15.8 Summary......Page 442 5.16 Research-Related Topics......Page 443 6 Multilayer Networks......Page 444 6.1.1 The ASON/ASTN Framework......Page 445 6.1.2 Protocols for Implementing a Distributed Control Plane......Page 447 6.1.3 Overview of Control Plane Architectures (Overlay, Peer, Augmented)......Page 453 6.2 Generic Multilayer Recovery Approaches......Page 458 6.2.1 Why Multilayer Recovery?......Page 459 6.2.2 Single-Layer Recovery Schemes in Multilayer Networks......Page 460 6.2.3 Static Multilayer Recovery Schemes......Page 465 6.2.4 Dynamic Multilayer Recovery......Page 478 6.3 Case Studies......Page 485 6.3.1 Optical Restoration and MPLS Traffic Engineering Fast Reroute......Page 486 6.3.2 SONET/SDH Protection and IP Routing......Page 490 6.3.3 MPLS Traffic Engineering Fast Reroute (Link Protection) and IP Rerouting Fast Convergence......Page 492 6.4 Conclusion......Page 497 Bibliography......Page 500 List of Figure Sources......Page 512 Index......Page 518 Network Recovery is the first book to provide detailed information on protecting and restoring communication networks, and it sets a sky-high standard for any that may follow. Inside, you’ll learn specific techniques that work at each layer of the networking hierarchy—including optical, SONET-SDH, IP, and MPLS—as well as multi-layer escalation strategies that offer the highest level of protection. The authors begin with an incisive introduction to the issues that define the field of network protection and restoration, and as the book progresses they explain everything you need to know about the relevant protocols, providing theoretical analyses wherever appropriate. If you work for a network-dependent organization, large or small, you’ll want to keep Network Recovery within reach at all times.

* Shows you how to implement protection and recovery techniques that will save your organization time and money.
* Documents techniques for the optical, SONET-SDH, IP, and MPLS layers, as well as multi-layer escalation strategies.
* Shows you how to evaluate these techniques in relation to one another, so you can develop an optimal network recovery design.
* Provides industry examples and simulation results.
* Delves into the inner workings of relevant protocols and offers theoretical analyses wherever this information contributes to your practical knowledge.