Efficient Approach towards Energy
Minimized Optical Network
Nakarmi Bikash, J. Sangirov, M. Rakib Uddin, Y. H. Won
Korea Advanced Institute of Science and Technology
Photonic Energy and Signal processing Lab
Daejeon,
Republic
of2010Korea
1
Efficient Approach towards Energy Minimized Optical Network
@ITU-T workshop
at Shanghai Expo
Outline
Introduction Needs, Scenario & Approaches
Our Focus
Targets & Achievement
Further Improvement
Conclusion
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010
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Introduction: why growing issue of energy consumption
Growing Issues on Environment : Simultaneous threat against the global
environment and resources
• Threat against the existence of human race due to weather disasters and
ecological destruction
• Economic loss predicated if energy mass consumption system continues:
5~20% of annual world GDP(’06, Stern Review)
• Shortage of energy resources and increase in price
• Caused by economic development of new developing countries and continuous
growth in world population
Summer Period
: Jun.3~sep.21(1920s)
-> May 24~Sep.27(1990s)
: 16days increase
Winter Period
: Nov. 21 ~ Mar. 18(1920s)
->Nov. 29~ Mar. 8 (1990s)
: 19 days decrease
Source: METRI Korea , 2006
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010
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Introduction: Scenario in optical n/w & approaches
In past no any concern with the power consumption on the optical network
Power issue is also being taken as a resource and more focus drawn
towards its efficient use
Energy Saving Optical Technologies Tendency
•All-optical technology as the solution of electronic bottleneck.
• Current trends of developing the electronics devices: compact size higher speed
• As concerned more about power and development of electronics high speed
devices the trends moves to the hybrid
Finding the ways to improve power efficient networks
• Component level design (Improve electronic technology for the hybrid system)
• Power aware protocol design (low energy states)
• Power aware network design (New architecture i.e. bypassing )
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010
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Multi-disciplinary approach Tendency towards
Future Green Internet
Power consumption
based on telco data
Projected services
take up
Strategies to
minimise power
consumption
Power consumption
based on vendor specs
New optical
technologies
Telco network
architectures
New paradigm
for power
minimisation
New router
architectures
Green Internet
Internet today
Power forecast based on current technologies
Power forecast based on new technologies
New mix of
electro & opto
New protocols
New network
architectures
source: MERIT, Australia
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010
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Reasons for moving to Hybrid Technology:
Current trends of developing the electronics devices: compact size
higher speed
Not necessarily introduce system benefits on the all optical systems
due to transparency
Power Aware Protocol Designing
100
Nearly 70% by BW.
Allow generic long packets
80
Ethernet MTU
60
TCP default
Nearly 70% of switching times
Switching by flow bursts
AREA o research
40
20
0
500
1500
2500
3500
4500
source: Thompson, Miller, Wilder 1997
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010
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Dominance of Access Network
in IP Related Processing
Source: R. Tucker, OFC 2007, photonics in Switching, San francisco, 2007
: Routing & packet protocol engineering
may reduce energy consumption.
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010
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Present scenario of Power Consumption in
Optical Network
25
10 router hops
20
1.0
15
Today’s Internet
(~ 2.5 Mb/s)
Core
10
0.5
Access
5
Metro
SDH/WDM Links
0
% of Electricity Supply
Power (W/user)
Total
0
0
50
100
150
Peak Access Rate (Mb/s)
200
250
Source: R. Tucker, OFC 2007
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010
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Our Focus: Present Scenario
Still need of the OEO wavelength converter in our proposed hybrid PSMB
Power consumption (%)
120
100
80
optical amp.
wavelength converter
60
photonics switch
40
client O/E/O
optical Mux/Demux
20
0
32
100
200
400
600
800
source: Makoto Murakami and Kazuhiro Oda
ICTON 2009
Number of Ports
Power consumption by various components in optical network
So further approach should be taken on the minimizing of wavelength converter
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010
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Set-UP : Modification from the Past System PSMB
Very low power
consumption
On approach to the hybrid technology
we used the shared electronics buffer
Change all optical wavelength
converter to the OEO wavelength
converter
Change the Node architecture
λ1
λ2
λ1
λ2
λw
λw
λ1
λ2
λ1
λ2
λw
λw
λ1
λ2
λ1
λ2
λw
λw
λ conversion
source: J. Kevin Lee, KAIST ICC
workshop 2010
Performance of PSMB with different sharing ratio
Shared Electrical
memory buffers
Hybrid optical packet node architecture (PSMB)
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010 10
Wavelength Converters
clock
recovery
λin
λin
mechaoptical
delay
clock
recovery
data
recovery
OBF
CMOS driver
Buffer
tOBF
λintermediate
tunable Tx, λout
tunable LD, λout
OEO wavelength converter
OOO wavelength converter (using SOA)
Item
Cooled laser diode
Power (W)
10G
40G
Relative cost
10G
40G
0.6
0.6
0.35
0.35
0.8
0.8
0.5
0.5
0.2
0.2
0.1
0.1
Cooled tunable
laser diode
Adjustable optical
delay
4 cooled SOAs
Rx CDR
1.2
0.2
1.2
1.2
1.4
0.15
1.4
0.6
PIN-TIA
0.13
0.30
0.30
Total
3.13
4.5
2.8
Power (W)
40G
Relative cost
Item
10G
10G
DML diode
0
0.35
DML driver
EML diode
with TEC
0.42
0.20
40G
1.00
0.7
0.60
0.8
0.25
1.50
0.15
0.6
1.0
EML driver
Tx-Rx Mux
and CDR
PIN-TIA
0.13
0.30
0.30
1.0
3.95
Total
0.80
3.40
1.00
3.1
Table: Power & cost comparison of WCs using OEO & SOA
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010 11
Power & Cost Comparison of PSMB & Exiting
Architecture
Major
Component
OEXC
PSMB
ASDB
8000
40G
2 W (N+B)
WB/ WFDL
FDL
SOA
W (N-B)
Electro-optic
switch
(2x2)
W N (log2N+1)
WB
10G
Power (W)
Tunable WC
6000
4000
2000
0
EOXC
Interface
(E/SR & SR/E)
TRx
(SR/E/O &
O/E/SR)
WN
WN
W B (log2WB ½)
WB
WB
Table: Major components counts in Node Models
ASDB
10000
Cost (Arbitrary Unit)
Electronic switch
W N (log2WN - ½)
(2x2 at 10 or 40G)
PSMB
40G
10G
8000
6000
4000
2000
0
EOXC
PSMB
ASDB
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010 12
Target & Achievement
Target
Moving towards the Hybrid
technology
Reduce Power consumed
Achievement
Obtained by using shared
electronics buffer and Optical
switch fabric
About 50% reduction is achieved
using the proposed Node
Architecture
Reduce on total cost
About 1/3 cost reduction
achieved
Changing the Wavelength
converter Technology
From OOO to OEO wavelength
converter
Modifying the Present Node
Architecture
(ASDB)
Proposed a new Node
architecture (PSMB)
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010 13
Further Approaches To be Taken
Modifying in the electronics switch part
Buffer the input data on the basis of lambda so if needed then
use the wavelength converter and if not needed of the conversion
bypass it.
This features not only reduce the number of wavelength
converter but also reduces the number of locking of different
wavelength
As each locking process will have some amount of more power
consumption it can reduce the power as it is reducing the number
of converting different frequency
Finally obtain the power reduction up to 75% and cost
reduction to the 30% than that of traditional node architecture
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010 14
Traffic grooming modification for reducing
number of WCs
Source : N8
Destination : N9
Paths : {8,1,3,2,9}
{8,4,3,2,9}
{8,4,5,7,9}
{8,4,6,7,9}
Groomed paths:
{8,4,5,7,9}
{8,4,6,7,9}
Reduced 1 wavelength converter
Representation of a physical route from source to destination
(a) Wavelength layered model (b) lambda run model (c)) lambda run graph
Efficient Approach towards Energy Minimized Optical Network @ITU-T workshop at Shanghai Expo 2010 15
Conclusion
Only photonics solution seem not to help so approach should
be towards Hybrid Technology
Shows the significant power and cost saving with proposed
PSMB Switching Node
Usage of shared Buffer and Wavelength converter can
minimize the power
Modifying the WCs from OOO to OEO WCs
Further improvement can be made by reducing number of
wavelength converter and minimizing the transition of converted
wavelength
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