All-optical Packet Router Employing PPM Header Processing

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All-optical Packet Router Employing PPM Header
Processing
Prof. Z. Ghassemlooy Optical Communications
Research Group http//soe.unn.ac.uk/ocr/ School
of Computing, Engineering and Information
Sciences Northumbria University Newcastle, UK
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Presentation Outline

1. Introduction
2. Original Contributions and Research Outcomes
3. Future Work

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CEIS - Research Groups
Northumbria Communications Research Laboratories
Advanced Signal Processing
Non-Linear Control
Network Security
Microwave and Microwave Holography Active
Antenna
Optical Communications Research Group (OCRG)
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OCRG People

• Staff
• Prof. Z Ghassemlooy
• J Allen
• Dr R Binns
• Dr K Busawon
• Dr W. P. Ng
• Visiting Academics
• Prof. V Ahmadi, Univ. Of Tarbiate Modaress ,
  Tehran, Iran
• Dr M. H. Aly, 2Arab Academy for Scie. and Tech.
  and Maritime Transport, Egypt
• Prof. J.P. Barbot, France
• Prof. I. Darwazeh, Univ. College London
• Prof. H. Döring, Hochschule Mittweida Univ.
  of Applied Scie. (Germany)
• Prof. E. Leitgeb, Graz Univ. of Techn.
  (Austria)
• PhD Students M. Amiri, A. Chaman-Motlagh, M. F.
  Chiang, M. A. Jarajreh, R. Kharel, S. Y Lebbe, W.
  Loedhammacakra, Q. Lu, V. Nwanafio, E. K. Ogah,
  W. O. Popoola, S. Rajbhandari, A. Shalaby, X.
  Tang
• MSc A Burton, D Bell, G Aggarwal, M Ljaz, O
  Anozie, W Leong , S Satkunam

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WBU, India 2009
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OCRG Agilent Photonic Lab
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Optical Communications

• 1st generation optical networks packet routing
  and switching are mainly carried out using
  high-speed electronic devices.
• However, as the transmission rate continues to
  increase, electronically processing data
  potentially becomes a bottleneck at an
  intermediate node along the network.

• Solution All-optical processing switching

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Photonics - Applications

• Photonics in communications expanding and
  scaling

Metropolitan
Home access
Board -gt Inter-Chip -gt Intra-Chip

• Photonics diffusing into other application
  sectors

Health(bio-photonics)
Environment sensing
Security imaging
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Networks Topology An Overview
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O-E-O Router Architecture
http//www.cisco.com/en/US/products/ps5763/index.h
tml

• Up to 92 Tbit/s
• Optical inputs but electronic switching
• Very large power consumption

Dr N. Calabretta (TU/e, Holland)
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Why Photonic Technology
160 Gb/s -gt 622 Mb/s
All-optical

• High speed and parallel all-optical processing
  of the packets.
• Photonic integration potentially allows a
  reduction of volume, power consumption,
  scalability, latency and costs.

Dr N. Calabretta (TU/e, Holland)
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All-optical Packet Switching

• Objectives
• High Bit Rate
• High Throughput

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All-optical Cross-connect node

• Functionality 1 x N packet switch
• All-optical label recognition
• Low latency
• Scalable
• ? photonic integration
• All-optical label rewriting
• Optical routing
• Low power penalty
• ? Node cascadability

Target routing and label rewriting in a single
device
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Research Road Maps
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Packet Routing Header Processing
1. Optical vs. Electrical in High-speed Routing
H
Routing table
0100
Patterns Outputs
0000B (0D) OP1
0001B (1D) OP2
0010B (2D) OP1
0011B (3D) OP1
0100B (4D) OP2
0101B (5D) OP1

1110B (14D) OP2
1111B (15D) OP1
Matching!
Optical domain
Electrical domain
High Speed gtgt 40 Gbit/s
IC Large scale, cheap, memory
Complexity, costly, no memory
Speed limitation lt 40 Gbit/s
Integration
Light Frozen?
Opt. Capacitors?
All-Optical Processing
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Packet Routing Header Processing
N?2N bit-wise AND operations
Robust All-Optical Processing
Our solution Pulse-Position-Modulation based
Header Processing (PPM-HP)
Minimise number of AND operations
Reduce routing table entries
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Packet Routing Header Processing
3. What is Pulse Position Modulation?
Tb bit duration, Ts slot duration
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Packet Routing Header Processing
4. Pulse Position Routing Table (PPRT)
Conventional routing table
Address patterns Decimal metric Output ports
00000 0 Port 2
00001 1 Port 1
00010 2 Port 3
00011 3 Port 1
00100 4 Port 3
00101 5 Port 2
00110 6 Port 2
00111 7 Port 1

1110 2N-2 Port 2
1111 2N-1 Port 1
Entry Positions (Decimal) Actual PPM frame (length 2N slots)
1 1,3,7,,2N-1
2 0,5,6,,2N-2
3 2,4,
2N entries
PPM
Pulse-position routing table
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Packet Routing Header Processing
All-optical Switch
5. PPM-HP Router
Port 1
OSW1
Port 2

OSW2

Port M
OSWM
Header Extraction
PPM Add. Conversion
CP 1
CP 2
PPRT
CP M
OSWC
1
Entry 1

Clock Extraction
OSWC
Entry 2
2
Synchronization



Entry M
OSWC
M
PPM-HP
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Packet Routing Optical Switches
Cat.1 Large scale (gt 16?16) Slow response
(?s-ms) Non-optically controlled
Cat.2 Small scale (2?2) Fast response (fs-ps)
Full-optically controlled
SMZ (Japan)

• Crosstalk

TOAD (Princeton)

• Contrast

Sources Internet articles websites
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Terahertz Optical Asymmetric Demultiplexer
(TOAD) Operation (1)

• Introduced by P. Prucnal (1993)
• Nonlinearity Semiconductor Optical
• Amplifier (SOA)
• Low control pulse (CP) power
• High inter-channel crosstalk
• Asymmetrical switching window profile
• Synchronisation

0
Non-switching
180
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TOAD - Operation (2)

• Introduced by P. Prucnal (1993)
• Semiconductor Optical Amplifier
• induces nonlinearity
• Low control pulse energy
• High inter-channel crosstalk
• Asymmetrical switching window
• profile

Switching
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Symmetric Mach-Zehnder (SMZ)
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Symmetric Mach-Zehnder (SMZ)
180
180
180
180
Switching window (SW) gain
SW width Delay interval between two control
pulses TSW
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VPI SMZ Switch
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PPM-HP Router - Clock Extraction
Optical packet
Clock, header and payload same intensity,
polarization and wavelength

• Clock extraction requirements
• Asynchronous and ultrafast response
• High on/off contrast ratio of extracted clock

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Packet Routing Clock Extraction
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Packet Routing Clock Extraction
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Simulation Clock Extraction
Packet in
Extracted clock
2nd stage
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Packet Routing PPM-HP Address Conversion
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Packet Routing PPM-HP Header Correlation

• SMZ-based AND gate only one bit-wise operation!
• SOA gain recovery is no longer an issue, since it
  is saturated only once for header recognition

Ref R. P. Schreieck et al., IEEE Quantum
Elec., Vol. 38, pp. 1053-1061, 2002
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Simulation Results - AND operation
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1?2 SMZ Switch with a High Contrast Ratio

CEM clock extraction module
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Packet Routing PPM-HP All-Optical Flip-Flop

• Operate at lt nanoseconds responses
• Multiple SET/RESET pulses for compensating the
  actual loop delay ( hundreds
• of picoseconds) and for speeding up the
  transient ON/OFF states of Q output

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Packet Routing PPM-HP Wavelength Conversion
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Packet Routing PPM-HP Demultoplexer

• SMZI
• Compact size (integrated)
• Ultrafast response (ps)
• Low energy (ltpJ)
• Flexible controlling schemes Wavelengths,
  Orthogonal polarizations, Propagation directions

• Multiple-channel demultiplexing
• Each channel demultiplexing requires one SMZ

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Packet Routing PPM-HP Chained Demultiplexer
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Fibre Delay Line Passive
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Fibre Delay Line Passive
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VPI PPM Routing Table
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Simulation Results Node Performance
0 1 1 1 0
Packet with address 01110
PPM-converted address
PPRT entry 1
Synchronized matching pulse
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VPI Simulation Software Router
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Packet Routing Multiple Routing Table
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Packet Routing Multiple Routing Table
All-optical Switch
Port 1
OSW1
Port 2

OSW2

Port M
OSWM
Header Extraction
PPM Add. Conversion
CP 1
CP 2
Multiple PPRT
CP M
OSWC

Entry 1
1
Clock Extraction
Entry 2
OSWC
2
Synchronisation



Entry M
OSWC
M
Group A
SW3
Group B
Multicast transmission
SW4
Multiple PPRT Generator
Group C
SW3
Group D
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Multi-hop Router
An optical core network with 32 edge nodes (4
hops)
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Simulation - Multiple-hop Routing
Node/Router 1
B broadcast M multicast

• Signal intensity is varied
• Noise level is increased

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Simulation Results Network Performance
Multiple-hop OSNR
Predicted simulated OSNRs
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Packet Routing PPM-HP WDM Router


PPM
-
H
P 1

WDM





MUX

Output 1


e

1
E

E

E

E

M
1
2
3
WDM
PPM
-
H
P 2





MUX


Output 2
...




WDM

e

DEMUX

Input

2


E

E

E

E

1
2
3
M


WDM




PPM
-
H
P

MUX

M



Output
M


e

M
E

E

E

E

1
2
3
M
All-optical packet-switched WDM router
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Simulation Results - Time Waveforms
Packets at the inputs of the WDM router
Packets observed at the output 2 of the WDM
router
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Future Work

• SIMO WDM Router

MIMO WDM Router ?
Will PPM-HP help for a contention solution? ?
(FIFO)

• PPM-HP

Further PPRT downsizing?
Multiple PPRTs ?
Address subsets ?
Router complexity?
PPM-Address ?

• Experimental Test-bed 4-SMZ Router

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Final Comments

• PPM-HP
• Provides ultrafast header processing
• Reduces the number of routing table entries
• Avoids the SOA recovery time during header
  correlation
• Operates in a large BW as employing SOA
• Supports multiple transmitting modes
  (uni/multi/broadcasting)
• Offers add/drop edge node scalability

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Acknowledgements

• To all my colleagues, RAS and PhD students,
• Northumbria University and CEIS School for
  Research Grants

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• Thank you!