All-optical Packet Router Employing PPM Header Processing Prof. Z. Ghassemlooy Optical Communications Research Group School of Computing, Engineering and Information Sciences Northumbria University Newcastle, UK WBU- India 09

Z Ghassemlooy Presentation Outline 1.Introduction 2.Original Contributions and Research Outcomes 3.Future Work WBU- India 09

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

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, 2 Arab 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 OCRG – People 4 WBU, India 2009 Z Ghassemlooy

5 OCRG – Agilent Photonic Lab

Z Ghassemlooy 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. 1P 100T 10T 1T 100G 10G 1G 100M [bit/s] Voice Data Total Traffic demand forecast (NEC–2001) Capacity increase : 2~4 times a year Bit cost decrease : 1/2 time a year  Solution: All-optical processing & switching WBU- India 09

Photonics - Applications WBU- India 09 Z Ghassemlooy Long-Haul MetropolitanHome access Board -> Inter-Chip -> Intra-Chip Photonics in communications: expanding and scaling Health (“bio-photonics”) Environment sensing Security imaging Photonics: diffusing into other application sectors

Z Ghassemlooy Networks Topology – An Overview WBU- India 09

O-E-O Router Architecture Up to 92 Tbit/s Optical inputs but electronic switching Very large power consumption WBU- India 09 Z Ghassemlooy Dr N. Calabretta (TU/e, Holland)

Why Photonic Technology All-optical Parallel electronic switch 160 Gb/s -> 622 Mb/s DeMuxDeMux Elect. DeMux Receivers 1 Clock recovery High speed and parallel all-optical processing of the packets. Photonic integration potentially allows a reduction of volume, power consumption, scalability, latency and costs. Photonic switch Demultiplexer Multiplexer Dr N. Calabretta (TU/e, Holland) lasers Mux Elect. Mux Mb/s -> 160 Gb/s Modulators

Z Ghassemlooy Objectives High Bit Rate High Throughput HeaderProcessing! All-optical Packet Switching WBU- India 09

All-optical Cross-connect node Functionality 1 x N packet switch 1.All-optical label recognition Low latency Scalable  photonic integration 2.All-optical label rewriting 3.Optical routing Low power penalty  Node cascadability Target: routing and label rewriting in a single device Iran August 2007 Z Ghassemlooy

Research Road Maps WBU- India 09

Z Ghassemlooy Packet Routing – Header Processing O/E Processing E/O PatternsOutputs 0000 B (0 D )OP B (1 D )OP B (2 D )OP B (3 D )OP B (4 D )OP B (5 D )OP 1 …… 1110 B (14 D )OP B (15 D )OP Matching! H Routing table Electrical domain IC: Large scale, cheap, memory Speed limitation < 40 Gbit/s Optical domain High Speed >> 40 Gbit/s Complexity, costly, no memory All-Optical Processing Integration Light “Frozen”? “Opt. Capacitors”? 1. Optical vs. Electrical in High-speed Routing WBU- India 09

Z Ghassemlooy Packet Routing – Header Processing Robust All-Optical Processing Packet header is compared with all entries of a routing table for checking the matching 2. Address Correlation N  2 N N  2 N bit-wise AND operations Reduce routing table entries Minimise number of AND operations Our solution: Pulse-Position-Modulation based Header Processing (PPM-HP) WBU- India 09

Z Ghassemlooy Packet Routing – Header Processing 3. What is Pulse Position Modulation? T b – bit duration, T s – slot duration TsTs PPM One Frame T f = 2 4 T s TbTb LSB Binary One Frame T f = 4T b WBU- India 09

Z Ghassemlooy Packet Routing – Header Processing 4. Pulse Position Routing Table (PPRT) Address patterns Decimal metric Output ports 00…0000Port 2 00…0011Port 1 00…0102Port 3 00…0113Port 1 00…1004Port 3 00…1015Port 2 00…1106Port 2 00…1117Port 1 ……… 11…102 N -2Port 2 11…112 N -1Port 1 2 N entries Entry Positions (Decimal) Actual PPM frame (length 2 N slots) 11,3,7,…,2 N -1 20,5,6,…,2 N -2 32,4,… PPM … N -1 … … Conventional routing table Pulse-position routing table 1M1M (M = 3 ports) Port 1 Port 2 Port 3 WBU- India 09

Z Ghassemlooy Clk Matched pulse … &1 Entry 1 Entry 2 … Entry M … CP 1 CP 2 CP M Port 1 Port 2 Port M PPM-HP All-optical Switch … &2 &M&M … … Clock Extraction Header Extraction PPM Add. Conversion PPRT … OSWC Synchronization APLClk APLClk APLClk APLClk PPMA A OSW1 OSW2 OSWM 5. PPM-HP Router Packet Routing – Header Processing WBU- India 09

Z Ghassemlooy Packet Routing – Optical Switches MEMS * (Lucent Tech.) Bubbles * (Agilent) TOAD * (Princeton) SMZ * (Japan) Cat.1 Large scale (> 16  16) Slow response (  s-ms) Non-optically controlled Cat.2 Small scale (2  2) Fast response (fs-ps) Full-optically controlled Crosstalk Contrast * Sources: Internet articles & websites WBU- India 09

Z Ghassemlooy Terahertz Optical Asymmetric Demultiplexer ( TOAD) – Terahertz Optical Asymmetric Demultiplexer ( TOAD) – Operation (1) Non-switching WBU- India 09 Introduced by P. Prucnal (1993) Nonlinearity: Semiconductor Optical Amplifier (SOA) Low control pulse (CP) power High inter-channel crosstalk Asymmetrical switching window profile Synchronisation

Z Ghassemlooy TOAD - Operation (2) Switching Introduced by P. Prucnal (1993) Semiconductor Optical Amplifier induces nonlinearity Low control pulse energy High inter-channel crosstalk Asymmetrical switching window profile WBU- India 09

Z Ghassemlooy No control pulse is applied Control pulses (CP1 & CP2) are applied Symmetric Mach-Zehnder (SMZ) WBU- India 09

Z Ghassemlooy Symmetric Mach-Zehnder (SMZ) Switching window (SW) gain: SW width: Delay interval between two control pulses T SW WBU- India 09

VPI – SMZ Switch WBU- India 09 Z Ghassemlooy Optical receiver Data pulse train

PPM-HP Router - Clock Extraction WBU- India 09 Z Ghassemlooy Clock extraction requirements: Asynchronous and ultrafast response High on/off contrast ratio of extracted clock Clock, header and payload: same intensity, polarization and wavelength Clock Extraction Clk Optical packet

Z Ghassemlooy Packet Routing – Clock Extraction WBU- India 09

Z Ghassemlooy Packet Routing – Clock Extraction WBU- India 09

Simulation – Clock Extraction WBU- India 09 Z Ghassemlooy 2 nd stage Packet in Extracted clock 1 st stage Crosstalk

Z Ghassemlooy Packet Routing – PPM-HP Address Conversion On / off contrast ratio against the timing offset of PPM header WBU- India 09

Z Ghassemlooy 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 , 2002 Packet Routing – PPM-HP Header Correlation AND gate A B A*B PP packet address … … One PPRT entry SOA1 SOA2  in  SW A B ABAB WBU- India 09

Simulation Results - AND operation WBU- India 09 Z Ghassemlooy

1  2 SMZ Switch with a High Contrast Ratio WBU- India 09 Z Ghassemlooy CEM: clock extraction module low inter-output CR (< 10 dB) Improved CR (> 32 dB)

Z Ghassemlooy Packet Routing – PPM-HP All-Optical Flip-Flop - Operate at < 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 WBU- India 09

Z Ghassemlooy Packet Routing – PPM-HP Wavelength Conversion SOA1 SOA2 2 Data 1 2222 2222 Data 2 WBU- India 09

Z Ghassemlooy Packet Routing – PPM-HP Demultoplexer SMZI Compact size (integrated) Ultrafast response (~ps) Low energy (<pJ) Flexible controlling schemes: Wavelengths, Orthogonal polarizations, Propagation directions Multiple-channel demultiplexing Each channel demultiplexing requires one SMZ WBU- India 09

Z Ghassemlooy Packet Routing – PPM-HP Chained Demultiplexer WBU- India 09

Fibre Delay Line – Passive WBU- India 09 Z Ghassemlooy A B C In Out Fibre loop Switch Eye diagram after 200 iterations without regeneration

Fibre Delay Line – Passive WBU- India 09 Z Ghassemlooy A B C In Out DSF fibre loop Switch Optical amplifier Optical regenerator Clock Eye diagram after 200 iterations with regeneration

Z Ghassemlooy VPI – PPM Routing Table WBU- India 09

Simulation Results – Node Performance Packet with address PPM-converted address PPRT entry 1 Synchronized matching pulse WBU- India 09 Z Ghassemlooy

VPI Simulation Software – Router WBU- India 09

Z Ghassemlooy Conventional RT Single PPRTMultiple PPRTs Packet Routing – Multiple Routing Table WBU- India 09

Z Ghassemlooy Clk Matched pulse … CP 1 CP 2 CP M Port 1 Port 2 Port M Multiple PPRT Generator All-optical Switch … &M&M Clock Extraction Header Extraction PPM Add. Conversion … OSWC Synchronisation APLClk APLClk APLClk APLClk PPMA a2a1a0a2a1a0 Entry 1 Entry 2 … Group A Multiple PPRT Group B Group C Group D SW4 SW3 a4a4 a3a3 a3a3 a 4 a 3 a 2 a 1 a x x x … Entry M … Matched pulse &1 APLClk … &2 Multicast transmission OSW2 OSWM OSW1 Packet Routing – Multiple Routing Table WBU- India 09

Multi-hop Router WBU- India 09 Z Ghassemlooy An optical core network with 32 edge nodes (4 hops)

Z Ghassemlooy Simulation - Multiple-hop Routing Node/Router 1 Node/Router 2 Node/Router 3 Signal intensity is varied Noise level is increased B B M B M B: broadcast M: multicast WBU- India 09

Simulation Results – Network Performance Multiple-hop OSNR Predicted & simulated OSNRs WBU- India 09

Z Ghassemlooy All-optical packet-switched WDM router WDM MUX WDM MUX Input Output 1 Output 2 WDM DEMUX … … WDM MUX e 1 e 2 e M … … … E 1 E 2 E 3 E M PPM-HP 1 PPM-HP 2 … … … PPM-HP M … OutputM... PK 1 PK 2 PK M... PK 3 E 1 E 2 E 3 E M E 1 E 2 E 3 E M M M M PK 1 PK 2 PK M PK 1 PK 2 PK M … … Packet Routing – PPM-HP WDM Router WBU- India 09

Simulation Results - Time Waveforms Packets at the inputs of the WDM router Packets observed at the output 2 of the WDM router

Z Ghassemlooy Future Work SIMO WDM Router PPM-HP  (FIFO) Will PPM-HP help for a contention solution?  (FIFO) PPM-HPFurther PPRT downsizing?  Multiple PPRTs   MIMO WDM Router   Address subsets  Router complexity?  PPM-Address  Experimental Test-bed: 4-SMZ Router WBU- India 09

Z Ghassemlooy 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 WBU- India 09

Z Ghassemlooy Acknowledgements To all my colleagues, RAS and PhD students, Northumbria University and CEIS School for Research Grants WBU- India 09

Z Ghassemlooy Thank you! WBU- India 09