1. How GreenTouch is
Making a Difference
Rod Tucker
Centre for Energy-Efficient Telecommunications
University of Melbourne

2. Global Technology Capacity
1E+24
1024
1E+23
1023
1022
1E+22
Capacity (bits, bits/year)
1021 Storage (bits)
1E+21
1020
1E+20
1019 Telecommunications
1E+19
(bits/year)
1018
1E+18
1985 1990 1995 2000 2005 2010 2015
Source: Hilbert and Lopez, “The world’s technological capacity to
store, communicate, and compute information,” Science, April 2011

3. Power Consumption of the Internet
1013
Total Power Consumption (W)
1012
Power
Consumption of
Internet
1011
1010
GreenTouch goal
109
2010 2015 2020 2025
Year
Sources: Hinton et al., Tucker, IEEE

4. Travel Replacement
Air Travel Business Meeting
~3000 kg Co2e/person return
Melbourne Bangalore
Video Conferencing
2 X 1 Gb/s for 16 hours
~ 10 TB
~50 kg Co2e/person

5. Summary
• Energy implications of network growth
– Methods for estimating network energy
• Energy modelling of the network, including data centers
• Key contributors to network energy consumption
• The gap between current practice and “fundamental” limitations
– Putting the factor of 1000 into context
• How GreenTouch is making a difference
• Why your organization should join GreenTouch

6. Estimating ICT Energy
1. Inventory & sales approach:
Sales
(units/year) Equipment
Total sock stock:
Lifetime
(years) - Residential
- Commercial
Residential
- Industrial Energy use:
Industrial - Residential Total
Commercial - Commercial energy
Equipment - Industrial
Usage
(hours/year) consumption:
- Residential
Power - Commercial
needs - Industrial
Power
management
Source: Kawamoto et al. 2001, LBNL-45917

7. Estimating ICT Energy
2. Transaction-based network modelling approach (GreenTouch):
– Calculate power of resources required to deliver services
– Network equipment depends on service type
– Include network design rules
Service Network path
General Web Fixed access + Metro/Edge (x2) + Long haul + Enterprise
Video Fixed access + Metro/Edge + Long haul + Enterprise
Peer to Peer Fixed access (x2) + Metro/Edge (x2) + Long haul
Mobile data Mobile + Metro/Edge (x2) + Long haul + Enterprise
Mobile voice Mobile (x2) + Metro/Edge + Long haul

8. Network Segmentation & Modeling
Storage Switch
IP Core Router
IP IP
TDM
Gateway Fibre
TDM TDM
WDM IP
IP
WDM WDM
TDM
TDM
Server
Data Centre WDM
WDM
Edge Broadband Core
Routers Network Gateways
ADM Metro/
Edge
Ethernet
TDM/WDM Switch
ring
ADM Switch Splitter
Fiber Fiber
Metro/Edge
DSLAM
Fiber Splitter
Fiber
Cu
DSLAM Switch Access
Base
Cu
station

9. Access Network
• Customer home terminal
– ADSL modem, ONU,
wireless/cable modem,..
Switch
• Access network Splitter Fiber GPON
field equipment
Cabinet
– PON splitter, Edge
FTTN
Node Splitter Cu
DSLAM, RF amps,.. VDSL2
DSLAM
• Central office equipment
PtP
– OLT, gateway, Fiber
Base
switch, base station,.. station
LTE
Fiber
RF Node
Gateway
Cu
HFC
RFAmp

10. Metro/Edge
• Ethernet switches and transport
• Border Network Gateway (BNG)
• Broadband Remote Access Server (BRAS)
• Metro transport (TDM, WDM)
• Edge routers
Broadband
Network
Metro/Edge Edge
Routers Gateways Ethernet
Network Switch
Broadband
Network ADM
Edge
Ethernet Gateways Routers
Switch
TDM/WDM
ADM ring
Access Access

11. Core Network
• Core routers & switches
– Number of router hops
• Long haul & submarine optical WDM transport
– EDFAs, Raman amps, transmit & receive units, etc
• TDM and WDM cross connects and OADM
– Wavelength Selective
Switches, MEMS Core Router Access
Core IP
IP
TDM
TDM EDFA
IP WDM
WDM
IP IP
TDM
Fibre
TDM TDM
WDM IP
IP
WDM WDM
TDM
TDM
WDM
WDM
Access Access

12. Data Centers and Content Servers
• Data centres
– Storage disks and arrays Internet
– Servers
– Local Access Networks
– Gateway router
Gateway
– Ethernet switches routers
• Enterprise networks
Switches
• Content Distribution Networks
– Centralised
Servers
– Distributed
– Nano Data Centres (Nada)
Storage

13. Energy Efficiency of Equipment
100 2010 Data
10
Energy per bit (nJ)
Sub-wavelength Wavelength
1
0.1
0.01
0.001
Core Ethernet WDM PIC FEC Optical MEMS
Router Switch Tx/Rx Tx/Rx Chip Amp OXC
Source: Tucker et al., 2009

14. Energy Efficiency of Equipment
20 nJ
Source: O. Tamm et al. BLTJ
Vol.14, No.4, p.311, 2010
Energy per Bit
10 nJ

15. Router Energy Efficiency Trends
Router Energy Efficiency
10000
Cisco AGS
Linear fit gives
~25% improvement p.a.
1000
Energy/Bit (nJ)
nano-Joules per bit
Wellfleet BCN
Actual improvement
may be declining
100 Cisco GSR 12000
Cisco GSR 12000b Cisco CRS 1
Avici TSR
10 ALU7750
Cisco CRS-3
Source: Neilson, 2011
1
1985 1990 1995 2000 2005 2010 2015
Year

16. Transport Energy Efficiency Trends
Marconi Wireless
10 8 Trans-Atlantic
Telegraphy
Energy/Bit/1000 km (mJ)
10 6 Fessenden
Coax
Trans-Atlantic Optical + Regen
10 4 Optical + EDFA
NY - Paris
First Trans-Atlantic
10 2
Newhaven - Azores
TAT-1
1 TAT-3
Key West - Havana
TAT-8
10 -2 TAT-5
TAT-10
~15% improvement p.a. TAT-9
10 - 4 TAT-11 Current
TAT-12/13
10 -6
1840 1860 1880 1900 1920 1940 1960 1980 2000 2020
Source: Tucker 2011 Year

17. Summary
• Energy implications of network growth
– Methods for estimating network energy
• Energy modelling of the network, including data centers
• Key contributors to network energy consumption
• The gap between current practices and “fundamental”
limitations
– Putting the factor of 1000 into context
• How GreenTouch is making a difference
• Why your organization needs to join GreenTouch

18. Access Network Consumption
30
Wireless
Power Per User (W)
20
FTTN
10 HFC
FTTP
FTTP is “greenest”
0
1 10 100 1000
Peak Access Rate (Mb/s)

19. Global Power Consumption
Total Network Power Consumption (W)
1012
Total (using 2010 Technology)
Total (15% p.a. efficiency
1011 improvements)
1010 Routers and PON
switches
Transport
109
40% p.a. Access Rate Growth
10% p.a. Growth in user numbers
108
2010 2015 2020 2025
Year
1.5 billion users Sources: Hinton et al., Tucker, JSTQE , 2011(b)

20. Energy per Bit
100 100
Total (using 2010 Technology)
Average Access Rate (Mb/s)
10
Energy per bit (mJ)
Routers 10
and switches
Total (15% p.a.
1.0 improvements)
1
PON
0.1
Transport
0.01 0.1
2010 2015 2020 2025
Year

21. “Theory” and Practice
Access Current
10-5
Trends
Routers and
Switches
Network Energy per bit (J)
10-6
3
10-7 X 10
Transport
X 102
10-8
x 104
10-9 Switches Theoretical
Lower Bounds X 102
10-10
Transport
10-11
10-12
2010 2015 2020 2025
Year

22. Summary
• Energy implications of network growth
– Methods for estimating network energy
• Energy modelling of the network, including data centers
• Key contributors to network energy consumption
• The gap between current practices and “fundamental” limitations
– Putting the factor of 1000 into context
• How GreenTouch is making a difference
• Why your organization needs to join GreenTouch

23. GreenTouch Committee Structure
Executive Board
Operations
Technical Committee Committee
Services & Apps & Trends Committee Network Committee
Access Networks Core Networks
Working Fixed Mobile Core Core
Groups Access Communications Transmission Switching &
Networks Routing
Gee Rittenhouse
Peter Winzer Thierry Klein
Peter Vetter Jaffar Elmirghandi David Neilson
Rouzbeh Razavi
Subrat Kar (Tomorrow) (Tomorrow)
(Tomorrow)

24. Trends in PON
Questions
1000 • Can PON works at 40Gb/s?
Access-rate (Mb/s)
• Which architecture should we use?
• Which technologies can help reducing
the energy consumption?
100 IEEE 10G-EPON and ITU XG-PON
• 32 users @ 312Mb/s (20km)
• 64 user @155Mb/s (reduced
reach)
2000 2010 2020
Year • Standardized in ~2002
• Wildly deploy in last 5 years
• GPON : 16 users @ 155Mb/s
• EPON : 8 users @ 155Mb/s

25. Wireline Access Networks
Bit-Interleaved PON (Bi-PON)
DS: Bit-interleaved data
ONU 2
Line card
DS: 10Gbit/s ONU 1
OLT- BI
Tx ONT-FPGA
MAC DS
UNI
(FPGA) Rx BIPON
DS
Deser
Delta
DS: Packet data
ONU 2
Line card
DS: 10Gbit/s ONU 1
OLT- XGPON
MAC DS Tx ONT-FPGA
(FPGA)
UNI
Rx XGPON
DS
Deser
Peter Vetter (Tomorrow)

26. Future 40-Gb/s Access Options
Active Optical Splitter CWDM/TDM
40 Gb/s Burst lDS1 10 Gb/s Burst
lDS2
MUX
lDS3
DRIVER LD/Mod. lDS4 lDS1,..,lDS4 lDS2
WC ONU WC ONU
lUS1,..,lUS4 lUS2
TIA PD DCF OA lUS1
DEMUX
lUS2
lUS3
lUS4
OLT
Active optical splitter CWDM/TDM PON
lDS1 1.25 Gb/s 1.5mm 40 Gb/s 1.25 Gb/s
MUX
lDSN lDS,i
lDS1,..,lDSN DRIVER LD/Mod.
WC ONU
lUS1,..,lUSN lUS,i WC O/E E/O ONU
lUS1
DEMUX
1≤i≤N TIA PD Proc.
lUSN
OLT 1.3mm
DWDM
DWDM ElectronicSwitch
Electronic
Switch
Source. : Sedighi el al., Paper JTh2A.59 OFC’12

27. Power and Energy Consumption
32
Power consumption per user (W)
27 nJ/bit Aggregated rate : 40 Gb/s • TDM based
Number of ONU : 64 • > 10 Gb/s ONUs
• CMOS improvement is
16
Active optical splitter (AOS) more severe
5.7 nJ/bit CWDM-TDM
8
6 nJ/bit
DWDM
4 4.6 nJ/bit 2.5 nJ/bit
Electronic Switch (ES)
1.8 nJ/bit
2
2010 2012 2014 2016 2018 2020 • Non-TDM based
Time (year) • <1.25 Gb/s ONUs

28. Core Networks
IP
Core Switching
Core Switching Server TDM
& Routing
& Routing
Storage Core Network
Data Center
WDM
IP IP
Core Switching
Core Switching TDM TDM
& Routing
& Routing Core Optical Networks
& Transmission
......
Access
WDM WDM
Access

29. Core Switching and Routing
Scorpion (silicon photonic interconnect and single-chip linecard)

30. Core Switching and Routing
Opera (Optimal end-to-end resource allocation)

31. Summary
• Energy implications of network growth
– Methods for estimating network energy
• Energy modelling of the network, including data centers
• Key contributors to network energy consumption
• The gap between current practices and “fundamental” limitations
– Putting the factor of 1000 into context
• How GreenTouch is making a difference
• Why your organization needs to join GreenTouch

32. Collaboration Among Diverse Groups
Example: Fixed access networks
Un-cooled
Novel PON protocols;
tunable lasers
Virtual Low power CPE
PON Sleepmode
HGW
Min. energy access architectures
Fiber in the Home
Also:
Hybrid PON
TNO
ZTE, KAIST
Low power OFDM in
optical access

33. Exciting Projects
• BCG2: Beyond Cellular Green Generation*
• GTT: Green Transmission Technologies* *Cluster project made up of
• LSAS: Large Scale Antenna Systems* several sub-projects/activities
• Minimum Energy Access Architectures
• VHG: Virtual Home Gateway
• OPERA: Optimal End to End Resource Allocation
• STAR: Switching & Transmission
• REPTILE: Router Power Measurements
• Single Chip Linecard
• ZeBRA: Zero Buffer Router Architectures
• SEASON: Service Energy Aware Sustainable Optical Networks*
• HALF MOON: Highly Adaptive Layer for Mesh On-off Optical Networks
• EFICOST: Energy Efficient High Capacity OFDM Signal Transmission
• Telecommunication Audits and Data Aggregation
An Opportunity to Reinvent the Internet

34. Conclusions
• GreenTouch goal
– Reduce energy per bit by 1000 in a 2020 target network
– Requires 100 times more improvement than achievable via Moore’s Law
• Multi-pronged approach
– Fixed access
– Wireless access
– Switching and routing
– Core networking
– Services and applications
• Great strides have been made – more to come
• Greentouch needs you