Synchronous Ethernet and IEEE 1588 in Telecoms Next Generation Synchronization Networks

This book addresses the multiple technical aspects of the distribution of synchronization in new generation telecommunication networks, focusing in particular on synchronous Ethernet and IEEE1588 technologies. Many packet network engineers struggle with understanding the challenges that precise synchronization distribution can impose on networks. The usual ?why?, ?when? and particularly ?how? can cause problems for many engineers. In parallel to this, some other markets have identical synchronization requirements, but with their own design requirements, generating further questions. This book attempts to respond to the different questions by providing background technical information. Invaluable information on state of-the-art packet network synchronization and timing architectures is provided, as well as an unbiased view on the synchronization technologies that have been internationally standardized over recent years, with the aim of providing the average reader (who is not skilled in the art) with a better understanding of this topic.

The book focuses specifically on synchronous Ethernet and IEEE 1588 PTP-based technologies, both key developments in the world of synchronization over the last 10 years. The authors address the needs of engineers and technical managers who are struggling with the subject of synchronization and provide an engineering reference for those that need to consider synchronization in NGN. The market applications that are driving the development of packet network synchronization and timing architectures are also discussed. This book provides a wide audience with everything they need to know when researching, implementing, buying and deploying packet synchronization architectures in telecommunication networks.

Foreword xi

Abbreviations and Acronyms  xv

Acknowledgments  xxvii

Introduction xxxiii

Chapter 1. Network Evolutions, Applications and Their Synchronization Requirements 1

1.1. Introduction 1

1.2. Evolution from plesiochronous digital hierarchy to optical transport networks  3

1.2.1. Plesiochronous digital hierarchy and public switch telephone networks 3

1.2.2. Evolution toward SDH and synchronous optical network 7

1.2.3. Introduction of optical transport network in transport networks 11

1.3. Migration and evolution in the next-generation networks: from time division multiplexing to packet networks 12

1.3.1. Circuit emulation synchronization requirements 14

1.4. Mobile networks and mobile backhaul 17

1.4.1. Synchronization requirements in mobile networks 22

1.5. Synchronization requirements in other applications 27

1.6. The need to define new synchronization technologies 28

1.7. Bibliography  30

Chapter 2. Synchronization Technologies 33

2.1. Fundamental aspects related to network synchronization 33

2.2. Timing transport via the physical layer 42

2.2.1. Synchronous Ethernet 42

2.3. Packet timing  47

2.3.1. Packet timing using traffic data 47

2.3.2. Packet-based methods 52

2.4. IEEE 1588 and its Precision Time Protocol 55

2.4.1. Some essentials of IEEE 1588 56

2.4.2. IEEE 1588-2002: origin and limitations 64

2.4.3. IEEE 1588-2008 and PTPv2 68

2.5. The concept of “profiles” 75

2.5.1. Frequency profile 77

2.5.2. Phase and time profile (ITU-T G.8275.1) 81

2.6. Other packet-based protocols 82

2.6.1. Packet-based timing: starting with CES 82

2.6.2. Dedicated timing TDM PW 86

2.6.3. NTP  87

2.6.4. Summary and comparison 91

2.7. GNSS and other radio clock sources 94

2.7.1. Global and regional space-based timing system 94

2.7.2. Regional terrestrial systems 102

2.7.3. Comparison  104

2.8. Summary 105

2.9. Bibliography  107

Chapter 3. Synchronization Network Architectures in Packet Networks 111

3.1. The network synchronization layer 111

3.1.1. Network layers and abstraction 111

3.1.2. The synchronization layer 116

3.2. Functional modeling  117

3.3. Frequency synchronization topologies and redundancy schemes using SyncE 119

3.3.1. Introduction  119

3.3.2. Network topologies 120

3.3.3. Redundancy and source traceability 121

3.3.4. Use of SSM in real networks 122

3.3.5. Networks involving SSUs 130

3.3.6. Classical errors during SSM configuration 131

3.3.7. Conclusion on synchronization topologies 133

3.4. The IEEE 1588 standard and its applicability in telecommunication networks 133

3.5. Frequency synchronization topologies and redundancy schemes using IEEE 1588 134

3.5.1. Redundancy schemes using IEEE 1588 136

3.6. Time synchronization topologies and redundancy schemes 139

3.6.1. Locally distributed PRTC 140

3.6.2. Packet-based method 141

3.6.3. Resiliency and redundancy schemes 142

3.7. Bibliography  146

Chapter 4. Synchronization Design and Deployments 149

4.1. High-level principles 149

4.1.1. Network evolution  152

4.1.2. Typical mobile networks requirements and evolutions 158

4.2. MAKE or BUY network synchronization strategies 161

4.2.1. Relationships between MAKE or BUY strategies for network connectivity and Synchronization 162

4.2.2. MAKE or BUY network synchronization source strategies 167

4.2.3. Fixed/mobile network scenarios 170

4.3. Deployment of timing solutions for frequency synchronization needs 182

4.3.1. Overview of synchronization solutions for frequency needs 183

4.3.2. Synchronous Ethernet deployments 184

4.3.3. IEEE 1588 end-to-end deployments 196

4.4. Deployment of timing solutions for accurate phase/time synchronization needs 220

4.4.1. GNSS deployments and associated issues 221

4.4.2. IEEE 1588 full timing support deployments 225

4.4.3. Possible migration paths toward IEEE 1588 phase/time profile  236

4.5. Bibliography  237

Chapter 5. Management and Monitoring of Synchronization Networks  239

5.1. Introduction 239

5.2. Network management systems and the telecommunications management network (TMN) 240

5.3. Synchronization Network management: the synchronization plan and protection 242

5.4. Provisioning and setup: manual versus automatic 245

5.5. Monitoring functions  246

5.6. Management issues in wireless backhaul 249

5.7. Network OS integration: M.3000 versus SNMP 250

5.8. Bibliography  252

Chapter 6. Security Aspects Impacting Synchronization 255

6.1. Security and synchronization 255

6.1.1. Terminology used in security 257

6.1.2. Synchronization in network security ensemble 259

6.2. Security of the timing source 261

6.2.1. Access security to device 262

6.2.2. GNSS signal vulnerability 263

6.2.3. Protecting and mitigating from compromise signal 270

6.3. Security of synchronization distribution 274

6.3.1. Security aspects of physical timing transmission 275

6.3.2. Security aspects of packet-based timing transmission 277

6.4. Synchronization risk management 282

6.5. Bibliography  284

Chapter 7. Test and Measurement Aspects of Packet Synchronization Networks 287

7.1. Introduction 287

7.2. Traditional metrics  287

7.3. Equipment configuration 292

7.4. Reference signals, cables and connectors 293

7.5. Testing Synchronous Ethernet 293

7.5.1. Testing the performance of SyncE EEC 294

7.5.2. Testing the ESMC protocol 304

7.6. Testing the IEEE 1588 end-to-end telecom profile 308

7.6.1. Testing the telecom profile – protocol 308

7.6.2. Testing the telecom profile – performance of packet networks 316

7.6.3. Testing the telecom profile – performance of a PTP packet slave clock  319

7.7. Bibliography  326

Appendix 1. Standards in Telecom Packet Networks Using Synchronous Ethernet and/or IEEE 1588 329

A1.1. Introduction 329

A1.2. General content of ITU-T standards 330

A1.2.1. Network level  330

A1.2.2. Equipment level 331

A1.2.3. Use of network and equipment specification 332

A1.3. Summary of standards 332

A1.3.1. Standards related to SyncE 333

A1.3.2. Standards related to IEEE 1588 end-to-end telecom profile for frequency 335

A1.3.3. Standards related to IEEE 1588 full timing support telecom profile for phase and time transport 337

A1.4. Bibliography  339

Appendix 2. Jitter Estimation by Statistical Study (JESS) Metric Definition 341

A2.1. Mathematical definition of JESS 341

A2.2. Mathematical definition of JESS-w 342

Permissions and Credits 345

Biography  349

Index  353

Jean-Loup Ferrant worked for Alcatel and Alcatel-Lucent until he retired in 2009, then he continued being Rapporteur of ITU-T SG15Q13 sponsored by Calnex Solutions.

Mike Gilson is a Technical Specialist for BT on timing and synchronization based at Adastral Park, Martlesham Heath, UK. He represents BT in several standards bodies.

Sébastien Jobert is an R&D expert on synchronization, QoS and performance of telecom networks at France Télécom Orange Labs, Lannion, France.

Michael Mayer is an active contributor to ITU-T standards and a consultant in timing and synchronization.

Laurent Montini is a Technical Leader, based in France, and working in the Corporate Consulting Team within the Research and Advanced Development organization at Cisco.

Michel Ouellette is V.P. of Engineering at Iometrix in San Francisco, California, USA, specializing in conformance testing of packet network technologies such as Carrier Ethernet 2.0, MPLS, IEEE1588, SyncE.

Silvana Rodrigues is Director of System Engineering at IDT in Ottawa, Canada. She represents IDT in several synchronization standards committees.

Stefano Ruffini is the synchronization expert representing Ericsson in various standardization bodies. He works in Pisa, Italy in the Research & Innovation Team within the IP & Broadband Development Unit at Ericsson.