Optical Switching in Next Generation Data Centers (eBook)

Dr. Francesco Testa is Principal Researcher at Ericsson Research in Pisa. He received the Engineering degree , summa cum laude, from the University of Rome in 1980. In 1982 he received a scholarship from Fondazione Ugo Bordoni in Rome, for researching on integrated optics.  He started working in 1985 at Alcatel-Face Italy on the research of coherent optical systems. He joined Ericsson in Rome  in 1991, where he worked on the first demonstrations of WDM transport  systems in the framework of the European projects RACE and ACTS. He was later involved in the hardware design and development of transmission and switching equipments for SDH, DECT, Local Multipoint Distribution System (LMDS),  GSM and Access networks products. He is currently engaged in the research on optical systems and photonic integrated technologies for 5G and data center networks. He has co-authored many papers in the field of optical communications and he was invited speaker at ECOC 2015 conference in Valencia and at the SPIE Conference on Silicon Photonics and Photonic Integrated Circuits in Brussels in 2012. He holds more than 40 patents. He is the technical coordinator of the IRIS project in the FP7 European Union Framework Program. He has co-authored a chapter of the book Silicon Photonics III edited by Lorenzo Pavesi and David Lockwood, Topics in Applied Physics vol 122 (Springer-Verlag, 2016). Dr. Lorenzo Pavesi is a Professor of Experimental Physics, director of the Nanoscience Laboratory  and head of the Department of Physics at the University of Trento. He received his PhD in Physics in 1990 at the Ecole Polytechnique Federale of Lausanne). He founded the research activity in semiconductor optoelectronics at the University of Trento and started several laboratories of photonics, growth and advanced treatment of materials. He was the first president and founder of the IEEE italian chapter on Nanotechnology. His interests encompass classical and quantum integrated silicon photonics.  He is a frequently invited reviewer, monitor or referee for photonics projects by several grant agencies. He is an author or co-author of more than 400 papers, author of several reviews, editor of more than 20 books (including the successful books Silicon Photonics I,II,III, Topics in Applied Physics, Springer-Verlag), author of 2 books and holds 7 patents. He is chief specialty editor of the section Optics and Photonics of Frontiers in Materials, and in the editorial board of APL Materials and Research Letters in Physics.. In 2010 and 2011 he was elected distinguished speaker of the IEEE- Photonics society. He is a fellow of IEEE and senior member of SPIE. He holds an H-number of 53 according to the web of science and of 64 according to Google Scholar.

Preface 6
Contents 11
Part I: System Aspects of Intra Data Center Networking 13
Chapter 1: Photonics in Data Centers 14
1.1 Introduction: Recent Trends and Future Challenges of Data Centers and Cloud Computing 14
1.2 New Directions for Data Centers with Embedded Photonics 18
1.3 Arrival of Embedded Photonics, Silicon Photonics, and Heterogeneous 2.5D and 3D Integration 20
1.4 OE-PCBs and OE-Backplanes 22
1.4.1 High-Radix Optical Switches 22
1.5 Software-Defined Elasticity in Data Centers and Clients 25
1.6 Summary 28
References 29
Chapter 2: Optical Switching in Datacenters: Architectures Based on Optical Circuit Switching 33
2.1 Introduction 33
2.2 Optical Circuit Switching in Datacenter Networks 36
2.3 Agile Optical Datacenter Network Architecture 46
2.4 Conclusions 51
References 52
Chapter 3: Optical Switching in Data Centers: Architectures Based on Optical Packet/Burst Switching 55
3.1 Introduction 55
3.2 Data Center Networks: Requirements and Challenges 56
3.3 Optical Data Center Networks 58
3.4 Optical Packet and Burst Switching Technologies 59
3.4.1 Technical Challenges in OPS/OBS Data Centers 61
3.5 Optical DCN Architecture Based on OPS/OBS 62
3.5.1 Based on OBS 62
3.5.1.1 OBS with Fast Optical Switches 62
3.5.1.2 Optical Burst Rings 63
3.5.1.3 HOS Architecture 63
3.5.1.4 HOSA Architecture 64
3.5.1.5 Torus-Topology DCN 64
3.5.1.6 LIGHTNESS DCN Architecture 66
3.5.2 Based on OPS 66
3.5.2.1 IRIS Project: Photonic Terabit Routers 66
3.5.2.2 Petabit Optical Switch 67
3.5.2.3 Hi-LION 68
3.5.2.4 OSMOSIS Optical Packet Switch 69
3.5.2.5 Data Vortex 69
3.6 OPSquare DCN Based on Flow-Controlled Fast Optical Switches 70
3.6.1 Performance Investigation 72
3.7 Conclusions and Discussions 75
References 77
Part II: Demonstrations of Optical Switching in Data Center 80
Chapter 4: OSA: An Optical Switching Architecture for Data Center Networks with Unprecedented Flexibility 81
4.1 Introduction 81
4.2 Motivation and Background 83
4.2.1 A Motivating Example 83
4.2.2 Optical Networking Technologies 84
4.3 OSA Network Architecture 85
4.3.1 Building Blocks 85
4.3.2 Putting It All Together: OSA-2560 86
4.4 Network Optimization 87
4.4.1 Problem Formulation 88
4.4.2 Solution 89
4.5 Implementation 90
4.5.1 Test-bed Setup 90
4.5.2 Understanding the Optical Devices 91
4.5.3 Understanding the O-E-O Conversion 92
4.5.4 OSA System Performance 93
4.6 Discussion and Conclusion 96
References 98
Chapter 5: The Hi-Ring Architecture for Data Center Networks 100
5.1 Introduction 100
5.2 The Hi-Ring Architecture and Multidimensional Switching 101
5.3 Optical Subwavelength Switching and Synchronization 105
5.4 On-Chip Integration Using Silicon Photonics 109
5.5 Perspectives and Research Directions 112
References 112
Chapter 6: Low-Latency Interconnect Optical Network Switch (LIONS) 114
6.1 Introduction 114
6.2 Active LIONS Demonstrations 115
6.3 LIONS-LB Testbed Demonstration 117
6.4 All-Optical TOKEN/TONAK Demonstrator 120
6.5 Passive LIONS Demonstrations 127
6.6 Hierarchical All-to-All Eight-Node Demo 128
6.7 Flexible Bandwidth Optical Data Center Core Network with All-to-All Interconnectivity 129
6.8 Conclusions 133
References 134
Chapter 7: Torus-Topology Data Center Networks with Hybrid Optoelectronic Routers 135
7.1 Introduction 135
7.2 Torus Topology 136
7.3 Torus Data Center Networks 139
7.3.1 Optical Packet Switching 140
7.3.2 Optical Circuit Switching 142
7.3.3 Virtual Optical Circuit Switching 143
7.4 Hybrid Optoelectronic Router (HOPR) 144
7.5 Perspectives and Research Directions 149
References 150
Chapter 8: LIGHTNESS: All-Optical SDN-enabled Intra-­DCN with Optical Circuit and Packet Switching 152
8.1 Introduction 152
8.2 LIGHTNESS Data Plane Architecture 153
8.3 LIGHTNESS Control Plane Architecture 156
8.4 Technology Enablers for Flexible OCS/OPS 158
8.4.1 FPGA-Based Network Interface Card (NIC) 158
8.4.2 OPS Module 159
8.5 Experimental Demonstration and Evaluation 160
8.5.1 Overall Experimental Architecture 160
8.5.2 All-Optical Experimental Data Plane 163
8.5.3 SDN-Enabled Experimental Control Plane 163
8.5.4 Optical Data Center Virtualization Demonstration 164
8.5.5 Experimental Results and Evaluation 165
8.6 Conclusion: Discussions 167
References 169
Chapter 9: Hybrid OPS/EPS Photonic Ethernet Switch and Pure Photonic Packet Switch 171
9.1 Introduction 171
9.2 Hybrid OPS/EPS 172
9.2.1 Photonic Functions of Hybrid OPS/EPS 174
9.2.2 Experimental Setup of Hybrid OPS/EPS 176
9.3 Pure Photonic Packet Switching 178
9.3.1 Photonic Functions of Pure Photonic Packet Switch 179
9.3.2 Experimental Example and Results 183
9.4 Scalability of Photonic Packet Switch 185
9.5 Discussion and Conclusion 186
References 187
Chapter 10: OPMDC: Optical Pyramid Data Center Network 188
10.1 Introduction 188
10.2 OPMDC Architecture 189
10.2.1 Internal Design of ROADM and WXC Nodes 191
10.2.1.1 Tier-1 ROADM Node 192
10.2.1.2 Tier-2 WXC Node 193
10.2.1.3 Tier-3 WXC Node 194
10.2.2 Edge Capacity and Structure 194
10.3 Wavelength Allocation Strategies 196
10.3.1 Strategy 1: Static Wavelength Pre-allocation 196
10.3.2 Strategy 2: Relay-Based Wavelength Allocation 197
10.3.3 Strategy 3: Dynamic Wavelength Allocation 198
10.4 Prototype and Performance Assessment 199
10.4.1 OPMDC Prototyping System 199
10.4.2 Performance Assessment 199
10.4.3 Packet Latency Performance 201
10.5 Conclusions and Research Directions 202
References 202
Part III: Technologies for Optical Switching in Data Centers 204
Chapter 11: Commercial Optical Switches 205
11.1 Introduction 205
11.2 Microelectromechanical System-Based Optical Switch 206
11.3 Beam-Steering Optical Switch 209
11.4 Liquid Crystal Optical Switch 210
11.5 Electro-optic Switch 212
11.6 Semiconductor Optical Amplifier-Based Switch 214
11.7 Thermo-optic Switch 216
11.8 Comparisons and Discussions 218
References 219
Chapter 12: Silicon Photonics Switch Matrices: Technologies and Architectures 222
12.1 Introduction 222
12.2 Physical Effects and Mechanisms for Optical Switching in Silicon 223
12.2.1 Plasma Dispersion Effect 224
12.2.2 Thermo-optic Effect 227
12.3 Integrated Switching Cell Technologies 229
12.3.1 Mach-Zehnder Interferometer (MZI) Switching Cell 230
12.3.2 Resonant Switching Cell 232
12.3.3 Micro-electromechanical System (MEMS) Switching Cell 233
12.4 Integrated Matrices with ?s Response Time for Optical Circuit Switching 235
12.4.1 Crossbar Switch Architecture 235
12.4.1.1 64 × 64 Digital Silicon Photonics MEMS Switch Matrix 237
12.4.1.2 8 × 7 Switch Matrix Based on Resonant Switching Cells 239
12.4.2 PILOSS Switch Architecture 240
12.4.2.1 32 × 32 Si-Wire Switch Matrix 242
12.4.2.2 Micro-Opto-Electro-Mechanical Switch (MOEMS) Matrix 243
12.4.3 Switch and Select Architecture 244
12.4.3.1 8 × 8 Switch and Select Optical Matrix 245
12.5 Integrated Matrices with ns Response Time for Optical Packet Switching 246
12.5.1 Benes Switch Architecture 247
12.5.1.1 16 × 16 Benes Switching Matrix 248
12.5.1.2 32 × 32 Benes Switching Matrix 250
12.6 Silicon Photonics Wavelength-Selective Switch Matrix 250
12.7 Switch Matrices Comparison Table 254
12.8 Perspectives and Research Directions 254
References 257
Chapter 13: Trends in High-Speed Interconnects for Datacenter Networking: Multidimensional Formats and Their Enabling DSP 261
13.1 Introduction 261
13.2 Representation of a Lightwave and Polarization Rotation in Jones and Stokes Spaces 263
13.3 Evolution of Multidimensional Modulation Formats and Their Transceiver Architectures 265
13.4 Enabling DSP for Multidimensional Formats 269
13.5 State-of-the-Art Experimental Results Using Transceivers Realized by Discrete Components 272
13.6 Conclusion and Future Research Avenues 275
References 276
Chapter 14: Trends in High Speed Interconnects: InP Monolithic Integration 278
14.1 Introduction 278
14.2 The Building Blocks 279
14.3 Monolithic Technology 281
14.4 Transmitters 282
14.5 Receivers 286
14.6 Optical Switching 288
14.7 Outlook 290
References 291
Part IV: Prospects and Future Trends 297
Chapter 15: The Future of Switching in Data Centers 298
15.1 Introduction 298
15.2 Design Considerations for Advanced Optical Interconnects 300
15.3 Switch Architecture and Network Topology 302
15.4 Technology Trends 305
15.4.1 On-Chip Optical Interconnects 305
15.4.2 On-Board Optical Interconnects 306
15.4.3 System-Level Interconnection Network 308
15.5 Point-to-Point Interconnects 308
15.6 Optically Switched Interconnects 309
15.7 Enabling Technologies for Next-Generation System-­Level Optical Interconnection Networks 311
15.7.1 High-Capacity Optical Links 311
15.7.2 Bandwidth-Variable and Software-Controllable Optical Transceivers 313
15.7.3 Dynamic and Flexible Optical Switching Nodes 313
15.7.4 Energy-Efficient Communication Systems and Networks 314
15.7.5 Multilayer Software-Defined Networking 314
15.8 Conclusions and Future Research Directions 315
15.8.1 Optimizing the Architecture of Optically Switched Interconnects 317
15.8.2 Cross-Layer and Cross-Level Performance Analysis 318
15.8.3 Elastic and Software-Defined Optical Interconnects 318
15.8.4 Efficient Optical Interconnects 320
15.8.5 Scalable Routing and Load Balancing 321
15.8.6 Low-Latency and Efficient Optical Networks on Chip (NoC) 321
References 322
Correction to: Silicon Photonics Switch Matrices: Technologies and Architectures 326
Correction to: Chapter 12 in: F. Testa, L. Pavesi (eds.), Optical Switching in Next Generation Data Centers, https://doi.org/10.1007/978-3-319-61052-8_12 326
Index 327