a green internet · energy consumption. 1960. 1990. 2008 • dramatic growth of internet due to...
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A Green InternetA Green Internet
Rodney S. Tucker
ARC Special Research Centre for Ultra-Broadband Information Networks (CUBIN)
University of Melbourne
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Metro/Edge Network
Core Network
Energy Consumption and DataEnergy Consumption and Data
Energy
In
Video Distribution
Network
Data Center
Access Network
Data
Out
• Greenhouse Impact• Energy-limited capacity bottlenecks (“hot spots”)
• OPEX
• Enabling energy efficiencies in other sectors
Why is Energy Important?
The Internet
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Putting Things into ContextPutting Things into Context
“SMART 2020: Enabling the low carbon economy in the information age,” GeSI, 2008 www.gesi.org
Information and Communication Technologies (ICT)
Global Emissions GtCo2 e
Global Emissions
Emissions
ICTOther
Business as Usual 2020
2020 Abatements
5% of total
GtCO2 e
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SummarySummary
Estimating energy consumption of the Internet
Where does the energy go- Core, metro, access network?
What will happen as traffic grows over time?
Saving energy through travel replacement
Can photonic technologies help to build a Green Internet?
Caveat: “Making predictions is difficult – especially about the future.”
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EthernetSwitch
OLTSplitter
Cabinet
Metro/Edge NetworkCore Network
Network Energy ModelNetwork Energy Model
Edge Routers PON
Fiber
EDFA
Core Router
OXCROADM
Video Distribution Network
Storage
ServerServer
Storage
Data Center
Fiber
Access Network
DSLDSLAM
Cu
OLT
SwitchONU
Cabinet
PtP
FTTN
DSLAM
Fiber
Cu
Broadband Network Gateways
Hot spots
Tier 1 Network
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Estimating Energy ConsumptionEstimating Energy Consumption
Choose an access data rate (capacity per user)
Carry out paper design of network
Calculate the power consumed by the network per user
Repeat for all access rates
Peak access rate sold to userM =
Average access rate
Oversubscription~ 2.5 Mb/s in 2008
~ 0.1 Mb/s in 2008
M = 25
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2500
Pow
er (W
/use
r)
Baliga et al., 2008
0
20
25
5
Peak Access Rate (Mb/s)
15
100 20015050
10
Power Consumption of IP NetworkPower Consumption of IP Network
Total
Routers
Access (PON)SDH/WDM Links
Today’s Internet (~ 2.5 Mb/s)
2008 Technology10 core hops
Oversubscription = 25
% o
f Ele
ctric
ity S
uppl
y
0.5
1.0
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Pow
er (W
/use
r)
% o
f Ele
ctric
ity S
uppl
y
Baliga et al., 2008
Total
UltraUltra--Broadband AccessBroadband Access
Peak Access Rate (Mb/s)
00
2.550
100 5.0
Routers
Access (PON) SDH/WDM
0 1000500
2008 Technology10 core hops
Oversubscription = 25
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Power Consumption in Access NetworksPower Consumption in Access Networks
Wave7 ONT-G1000i
Splitter GPON
PtP
Cabinet
Edge Node
Cisco 6513
Hitachi 1220
NEC AM3160
Cisco 4503
NEC VF200F6
TC Communications TC3300
Axxcelera ExcelMax
Cabinet
Access N/W
FTTN VDSL2
Cu
Fiber
Fiber
Cisco uBR10012
RF Gateway Cisco DCP3000
HFCCu
RF Amp
Node
WiMAX
AxxceleraExcelMax BTS
Fiber
Hitachi 1220
Splitter
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30
Peak Access Rate (Mb/s)
Pow
er P
er U
ser (
W)
1 10000
PtP
PON
100
20
10
10
32 Customers M = 32
M = 1
M = 1
Power Consumption in Access NetworksPower Consumption in Access Networks
M = 1
PON FTTH is “greenest”
FTTN
WiMAXM= 10
20 users per sector
HFC
M= 10M= 1
M= Oversubscription
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LowLow--Power States in User ModemsPower States in User Modems
“With implementation of this Code of Conduct the (network) electricity consumption could be limited to 25 TWh per year. This is equivalent to 5.5 Millions tons of oil equivalent (TOE) and to total saving of about € 7.5 Billions per year.”
Off-State (W)
Low-Power State (W)
On-State (W)
ADSL-CPE 0.3 3.5 4.0
VDSL2-CPE 0.3 4.5 6.0
GPON ONU 0.3 5.0 9.0
PtP ONU 0.3 3.0 5.0
Extract:
EUROPEAN COMMISSIONDIRECTORATE -GENERAL JRCJOINT RESEARCH CENTREInstitute for the Environment and SustainabilityRenewable Energies Unit
Code of Conducton Energy Consumption of Broadband Equipment
Draft Version 3Issue 15 – 17 July 2008
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Energy consumption
20081960 1990
• Dramatic growth of internet due to “multimedia” traffic
– Any kind of video (on demand, time- shifted, faster than real time)
– Broadband Internet – Audio– Voice
• Broadband services require home network equipment
• Size of home networks increases with increasing number of devices
• Home equipment often not used efficiently
Gladish et al., ECOC 2008
Home NetworksHome Networks
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Total
Access (PON)Routers
2.5 25 250 2500
Ener
gy p
er b
it (μ
J)
1.0
1000
0.01
10
0.1
100
20 hops
~1 μJ/b
WDM Links
Peak Access Rate (Mb/s)
Network Network EnergyEnergy Consumption Consumption per Bitper Bit
~100 μJ/b
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Energy per Bit in Network DevicesEnergy per Bit in Network DevicesE
nerg
y pe
r bit
(nJ)
0.01
0.1
1
10
100
1000
MEMSOXC
OpticalAmp
PICTx/Rx
DiscreteTx/Rx
PoSTx/Rx
EthernetSwitch
CoreRouter
PONONU
(10 Mb/s)
IPTVServer
Sub-wavelengthWavelength
20082008
Estim
ated
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Router Capacity GrowthRouter Capacity Growth
Based on G. Epps, CISCO, 2006
1
10
100
1000
10000
1994 1996 1998 2000 2002 2004 2006
X 19
93 P
erfo
rman
ce
2008
CRS-1 (~1.3 Tb/s,13.6 kW/rack)
12416 (~0.3 Tb/s/rack)
12016 (~80 Gb/s/rack)
Year
Moore’s law x 2/18 m
Router capacity x 2.5/18 m
CMOS energy efficiency x 1.65/18 m
2010
40% p.a.
Router energy efficiency improving at 20% p.a. Neilson, JSTQE 2006
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25000
Pow
er (W
/use
r)
% o
f Ele
ctric
ity S
uppl
y
Baliga et al., 2008
0
20
0.5
25
5
Peak Access Rate (Mb/s)
15
100 20015050
1.0
10
Effect of Efficiency Gains?Effect of Efficiency Gains?
Total
Routers
Access (PON)SDH/WDM Links
2008 Technology10 core hops
Oversubscription = 25
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2500
Tota
l Pow
er (W
/use
r)
Baliga et al., unpublished
0
20
25
5
Peak Access Rate (Mb/s)
15
100 20015050
10
Overall Technology Efficiency Improvement Rate
= 0% p.a5% p.a
Traffic Growth rate = 40% p.a
20% p.aTarget
Improvements in Technology EfficiencyImprovements in Technology Efficiency
10% p.a
% o
f Ele
ctric
ity S
uppl
y
0.5
1.0
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• Optical transport (WDM) consumes relatively little energy< 5% of energy > 25% of CAPEX
• Access network dominates consumption at low rates– Standby/Sleep mode is key to reducing energy consumption– Energy efficiency may be a key driver for FTTH deployment
• Network routers dominate consumption at higher rates
• The “energy bottleneck” will replace the so-called “bandwidth bottleneck
• Electronics is excellent for switching and signal processing
• Photonics is excellent for transmission
Some ObservationsSome Observations
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• Alternatives for complex PC
• Sleep mode and fast “wake up”, adaptive modes of network and clients
• Power adaptive network
• Adaptive control of components based on communication requirements
• Adaptive sharing of content
• Highly efficient power adaptive processing
• Virtualization
Access Network Access Network
Global Packet Core
Network
Global Packet Core
NetworkECO - Server Application
Content ServerEfficient Clients and home networks
Application Content Server
Towards EnergyTowards Energy--Efficient NetworksEfficient Networks
After: Gladish et al., ECOC 2008
• Energy management solutions e.g. optical/electronic bypass
• Energy-efficient routing protocols
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Data CentersData Centers
1Koomey, 20082Revolutionizing Data Centre Efficiency—Key Analyses”McKinsey & Company, April 2008.
• Data center electricity consumption is ~1% of the global total1
• Energy consumption of data centers worldwide doubled between 2000 and 2006 2
• Incremental US demand for data centre energy between now and 2010 is the equivalent of 10 new power plants2
1 MW Data Center
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Each watt consumed by IT infrastructure carries a “burden factor” of 1.8 to 2.5 for power consumption associated with cooling, conversion/distribution and lighting
Sources: EYP Mission Critical Facilities, Cisco IT, Network World, Customer Interviews, APC
0
10
20
30
40
50
Server Storage Network
50% 35% 15%
Energy Consumption in a Data CenterEnergy Consumption in a Data Center
ICT Infrastructure Cooling
Conversion Loss
Lighting
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Using the Internet for Travel ReplacementUsing the Internet for Travel Replacement
Source: CISCO, 2008
Video Conferencing
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Travel Replacement Travel Replacement ––
Greenhouse Impact (C0Greenhouse Impact (C022 ))
~5,000 kg/person return
2 X 1 Gb/s for 24 hours = 20 TB
~100 kg/person
Air Travel
Video Conferencing
Melbourne Newport Beach
LEOS MeetingHome
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How much information does the brain hold?
420 TB 580 TBBrain Scans: Southern California Brain Research Institute (SCBRI)
Teleportation in place of Video Conferencing?Teleportation in place of Video Conferencing?
2,000 kg/person return
Rod Tucker John Marsh
(50 MW/person for 5 seconds to teleport in each direction)
Average LEOS member: (420 + 580)/2 ~ 500 TB
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Embarrassing Moments in Embarrassing Moments in SciSci FiFi
Beam me up, Scotty
Sorry, Captain. The power company has a
new energy-efficiency program. Please use Skype.
Teleportation
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Travel ReplacementTravel Replacement
5,000 kg/person returnAir Travel:
Teleportation: 2,000 kg/person return
Melbourne Newport Beach
100 kg/personVideo Conferencing:
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0.1
1
10
100
1,000
10,000
100,000
100 1 10 100 1000
Mb/s-hr
Dis
tanc
e tra
velle
d (k
m)
CarTrain
Plane
Tele-work
Travel
10
Gb/s-hr
Bitrate-Time Product
Bicycle
Telecommute
LEOS (in LA)
LEOS (in Melbourne)
RodRod’’s Telecommute Calculators Telecommute Calculator
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Low Energy Not so Low Energy
• PON Access networks- GPON, EPON- WDM PON
• Optical circuit switching
• Optical bypass- low-energy cross connects- ROADMs
• Photonic integration
• Optical interconnects- Low power Tx/Rx
• Low-energy nanophotonics
• Non-PON Access networks- Wireless- HFC- FTTN
• Sub-wavelength optical switching- Optical packet switching- Optical burst switching
• Nonlinear optics for logic & DSP
Green PhotonicsGreen Photonics
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““If you are thinking If you are thinking of competing with of competing with
CMOS, donCMOS, don’’tt””: : TingyeTingye Li, ~1998Li, ~1998
Sources: ITRS ’97-’06 Roadmaps; Hinton et al., JSTQE 2008
Sw
itchi
ng e
nerg
y E
s,J
Year
DeviceInput energy, Ei
Supply energy, Ep
Es = Ei + Ep
10-20
10-19
10-18
10-17
10-16
10-15
10-14
1995 2000 2005 2010 2015 2020 2025
Photon energy hν
@ 1.55 μm
CMOS
?
90 6545
3222
130180
250
18
10-13
10-12
~ 5 orders of magnitude
10-11
Switching energy
Photonic devicesHNLFSOAPPLNSi Nanowire
Feature size in nm
Every bit CountsEvery bit Counts
100 hν
@ 1.55 μm
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Major flaw: no mention of energy consumption
Energy per bit > 10 nJ/bit
I was WrongI was Wrong
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Some International AchievementsSome International Achievements
Source: Arthur Levin, ITU, 2008, S. Walker
• BT has reduced carbon emissions by 60% since 1996- Management compensation linked to reductions in energy consumption
• NTT has a major focus on reducing energy consumption - “Total Power Revolution” saved 124 million kWh in 2007
• Other initiatives: GeSI, Green Grid, WattWatt, FTTH Council Europe, EU codes of conduct, CBI Task Force etc.
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Groups and OrganizationsGroups and Organizations
http://www.gesi.org/
http://www.thegreengrid.org/home
http://www.itu.int/climate
http://wattwatt.com/
http://ictandclimatechange.com/
http://www.atis.org/0050/
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Workshops and ConferencesWorkshops and Conferences
• ITU Symposium on ICTs and Climate Change, London, 16-17 June, 2008:
http://www.itu.int/ITU-T/worksem/climatechange/index.html
• Network Solutions to Reduce the Energy Footprint of ICT, ECOC, Brussels, 21-25 September, 2008:
http://www.ecoc2008.org/programme.asp#greenict
• Symposium on Sustainability of the Internet and ICT, University of Melbourne, November 25-26, 2008:
http://www.ee.unimelb.edu.au/green_internet/
• Workshop on Energy Footprint of ICT: Forecast and Network Solutions, OFC 2009
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• Energy consumption of the Internet is small, but growing
• Internet energy consumption dominated by– Access network today– Core network in the future
• A multi-disciplinary approach is required to build a green Internet:– Improved efficiency in electronic and photonic devices– Low-energy switching techniques– Improved architectures– New protocols
• Photonics can play a key role– Think Energy
Summary Summary –– The Way ForwardThe Way Forward