The Role of Optics and Electronics in High-Capacity Routers

This paper examines the role of optical and electronic technologies in future high-capacity routers. In particular, optical and electronic technologies for use in the key router functions of buffering and switching are compared. The comparison is based on aggressive but plausible estimates of buffer and switch performance projected out to around 2020. The analysis of buffer technologies uses a new model of power dissipation in optical-delay-line buffers using optical fiber and planar waveguides, including slow-light waveguides. Using this model together with models of storage capacity in ideal and nonideal slow-light delay lines, the power dissipation and scaling characteristics of optical and electronic buffers are compared. The author concludes that planar integrated optical buffers occupy larger chip area than electronic buffers, dissipate more power than electronic buffers, and are limited in capacity to, at most, a few IP packets. Optical fiber-based buffers have lower power dissipation but are bulky. The author also concludes that electronic buffering will remain the technology of choice in future high-capacity routers. The power dissipation of high-capacity optical and electronic cross connects for a number of cross connect architectures is compared. The author shows that optical and electronic cross connects dissipate similar power and require a similar chip area. Optical technologies show a potential for inclusion in high-capacity routers, especially as the basis for arrayed-waveguide-grating-based cross connects and as components in E/O/E interconnects. A major challenge in large cross connects, both optical and electronic, will be to efficiently manage the very large number of interconnects between chips and boards. The general conclusion is that electronic technologies are likely to remain as integral components in the signal transmission path of future high-capacity routers. There does not appear to be a compelling case for replacing electronic routers with optically transparent optical packet switches

[1]  Hung-Hsiang Jonathan Chao,et al.  Next generation routers , 2002, Proc. IEEE.

[2]  Manolis Katevenis,et al.  Scheduling in Non-Blocking Buffered Three-Stage Switching Fabrics , 2006, Proceedings IEEE INFOCOM 2006. 25TH IEEE International Conference on Computer Communications.

[3]  S.J.B. Yoo,et al.  All-optical variable buffering strategies and switch fabric architectures for future all-optical data routers , 2005, Journal of Lightwave Technology.

[4]  S. Gosselin,et al.  160-Gb/s optical networking: a prospective techno-economical analysis , 2005, Journal of Lightwave Technology.

[5]  R.S. Tucker.  Petabit-per-second routers: optical vs. electronic implementations , 2006, 2006 Optical Fiber Communication Conference and the National Fiber Optic Engineers Conference.

[6]  A. Jourdan,et al.  Design and implementation of a multi-terabit optical burst/packet router prototype , 2002, Optical Fiber Communication Conference and Exhibit.

[7]  N. Olsson.  Lightwave systems with optical amplifiers , 1989 .

[8]  V. Lal,et al.  Widely tunable monolithically integrated all-optical wavelength converters in InP , 2005, Journal of Lightwave Technology.

[9]  J. Bowers,et al.  40-Gb/s optical buffer design and simulation , 2004, Proceedings of the 4th International Conference on Numerical Simulation of Optoelectronic Devices, 2004. NUSOD '04..

[10]  Wei Fang,et al.  Noise analysis of photonic packet synchronizer , 2004 .

[11]  Guido Appenzeller,et al.  Sizing router buffers , 2004, SIGCOMM '04.

[12]  Rodney S. Tucker,et al.  Photonic 2*2 packet switch with input buffers , 1993 .

[13]  N. Sahri,et al.  A highly integrated 32-SOA gates optoelectronic module suitable for IP multi-terabit optical packet routers , 2001, OFC 2001. Optical Fiber Communication Conference and Exhibit. Technical Digest Postconference Edition (IEEE Cat. 01CH37171).

[14]  A. Schweinsberg,et al.  Fundamentals and applications of slow light in room temperature solids , 2004, The 17th Annual Meeting of the IEEELasers and Electro-Optics Society, 2004. LEOS 2004..

[15]  Cyriel Minkenberg,et al.  Current issues in packet switch design , 2003, CCRV.

[16]  A. Naeemi,et al.  Polylithic integration of electrical and optical interconnect technologies for gigascale fiber-to-the-chip communication , 2005, IEEE Transactions on Advanced Packaging.

[17]  Ivan Andonovic,et al.  Approaches to optical Internet packet switching , 2000, IEEE Commun. Mag..

[18]  Wei Fang,et al.  Noise analysis of photonic packet synchronizer , 2004, Journal of Lightwave Technology.

[19]  Thomas F. Krauss,et al.  Flatband Slow Light in Photonic Crystal Waveguides , 2006 .

[20]  Monique Renaud,et al.  Transparent optical packet switching: The European ACTS KEOPS project approach , 1998, 1999 IEEE LEOS Annual Meeting Conference Proceedings. LEOS'99. 12th Annual Meeting. IEEE Lasers and Electro-Optics Society 1999 Annual Meeting (Cat. No.99CH37009).

[21]  Ivan Andonovic,et al.  Packet loss and delay performance of feedback and feed-forward arrayed-waveguide gratings-based optical packet switches with WDM inputs-outputs , 2001 .

[22]  S. Harris,et al.  Light speed reduction to 17 metres per second in an ultracold atomic gas , 1999, Nature.

[23]  Jacob B Khurgin,et al.  Expanding the bandwidth of slow-light photonic devices based on coupled resonators. , 2005, Optics letters.

[24]  Jacob Khurgin,et al.  Adiabatically tunable optical delay lines and their performance limitations. , 2005, Optics letters.

[25]  Katsuyoshi Washio,et al.  SiGe HBT and BiCMOS technologies for optical transmission and wireless communication systems , 2003 .

[26]  A. Yariv,et al.  Coupled resonator optical waveguides , 2002 .

[27]  V.W.S. Chan.  Guest Editorial. Optical communications and networking series , 2005 .

[28]  N. McKeown,et al.  Buffer sizing in all-optical packet switches , 2006, 2006 Optical Fiber Communication Conference and the National Fiber Optic Engineers Conference.

[29]  C. Chang-Hasnain,et al.  Slow-light in semiconductor quantum wells , 2004, InternationalQuantum Electronics Conference, 2004. (IQEC)..

[30]  Biswanath Mukherjee,et al.  Advances in photonic packet switching: an overview , 2000, IEEE Commun. Mag..

[31]  R.S. Tucker,et al.  Does optical burst switching have a role in the core network? , 2005, OFC/NFOEC Technical Digest. Optical Fiber Communication Conference, 2005..

[32]  Stefano Bregni,et al.  Architectures and performance of AWG-based optical switching nodes for IP networks , 2003, IEEE J. Sel. Areas Commun..

[33]  R.S. Tucker,et al.  A Taxonomy of Optical Buffer Architectures , 2006, COIN-NGNCON 2006 - The Joint International Conference on Optical Internet and Next Generation Network.

[34]  T. Kawahara.  Low-voltage embedded RAMs in the nanometer era , 2005 .

[35]  Rodney S. Tucker,et al.  Wavelength routing-based photonic packet buffers and their applications in photonic packet switching systems , 1998 .

[36]  Shun Lien Chuang,et al.  Variable optical buffer using slow light in semiconductor nanostructures , 2003, Proc. IEEE.

[37]  Nick McKeown,et al.  Part I: buffer sizes for core routers , 2005, CCRV.

[38]  Winston I. Way,et al.  Dynamic Range and Switching Speed Limitations of an N x N Optical Packet Switch Based on Low-Gain Semiconductor Optical Amplifiers , 2004 .

[39]  Ivan Andonovic,et al.  SLOB: a switch with large optical buffers for packet switching , 1998 .

[40]  P. Demeester,et al.  From IP over WDM to all-optical packet switching: economical view , 2006, Journal of Lightwave Technology.

[41]  Joon Tae Ahn,et al.  Low input power wavelength converter using gain-clamped semiconductor optical amplifier , 2002 .

[42]  Jacob B. Khurgin,et al.  Optical buffers based on slow light in electromagnetically induced transparent media and coupled resonator structures: comparative analysis , 2005 .

[43]  Rodney S. Tucker,et al.  Demonstration of photonic fast packet switching at 700 Mbit/s data rate , 1991 .

[44]  F. Ellinger,et al.  A 100-mW 4/spl times/10 Gb/s transceiver in 80-nm CMOS for high-density optical interconnects , 2005, IEEE Journal of Solid-State Circuits.

[45]  Winston I. Way,et al.  Dynamic range and switching speed limitations of an N/spl times/N optical packet switch based on low-gain semiconductor optical amplifiers , 1996 .

[46]  Ivan Andonovic,et al.  Buffering in optical packet switches , 1998 .

[47]  Jacob B Khurgin,et al.  Power dissipation in slow light devices: a comparative analysis. , 2007, Optics Letters.

[48]  Mario Martinelli,et al.  Linear and nonlinear pulse propagation in coupled resonator slow-wave optical structures , 2003 .

[49]  Liam O'Faolain,et al.  Dependence of extrinsic loss on group velocity in photonic crystal waveguides. , 2007, Optics express.

[50]  Richard A. Thompson,et al.  Photonic switching modules designed with laser-diode amplifiers , 1988, IEEE J. Sel. Areas Commun..

[51]  P. Kapur,et al.  Power comparison between high-speed electrical and optical interconnects for interchip communication , 2004, Journal of Lightwave Technology.

[52]  Rodney S. Tucker,et al.  Photonic Packet Switching: An Overview , 1999 .

[53]  Dominique Chiaroni.  Packet switching matrix: a key element for the backbone and the metro , 2003, IEEE J. Sel. Areas Commun..

[54]  M. Zirngibl,et al.  Optical switch fabrics for ultra-high-capacity IP routers , 2003 .

[55]  Chunming Qiao,et al.  Optical burst switching (OBS) - a new paradigm for an Optical Internet^{1} , 1999, J. High Speed Networks.

[56]  Honglin Wu,et al.  Power complexity of multiplexer-based optoelectronic crossbar switches , 2005, IEEE Transactions on Very Large Scale Integration (VLSI) Systems.

[57]  Christopher Leckie,et al.  Waveband grooming and IP aggregation in optical networks , 2003 .

[58]  R.S. Tucker,et al.  Optimization of pump and signal powers for wavelength converters based on FWM in semiconductor optical amplifiers , 1996, IEEE Photonics Technology Letters.

[59]  Piet Demeester,et al.  Multistage architectures for optical packet switching using SOA-based broadcast-and-select switches , 2003, OFC 2003 Optical Fiber Communications Conference, 2003..

[60]  H. Jonathan Chao,et al.  PetaStar: a petabit photonic packet switch , 2003, IEEE J. Sel. Areas Commun..

[61]  Idelfonso Tafur Monroy,et al.  An optical IM/FSK coding technique for the implementation of a label-controlled arrayed waveguide packet router , 2003 .

[62]  S. Dubovitsky,et al.  Relationship between the slowing and loss in optical delay lines , 2006, IEEE Journal of Quantum Electronics.

[63]  Paul R. Prucnal,et al.  Photonic packet switches: architectures and experimental implementations , 1994, Proc. IEEE.

[64]  L. Thylen,et al.  Limits on optical pulse compression and delay bandwidth product in electromagnetically induced transparency media , 2005, Journal of Lightwave Technology.

[65]  Lars Thylén,et al.  Switch energy requirements for first- and second-order perturbations in asymmetric quantum box optical switches , 1997 .

[66]  K. Komatsu.  Hybrid optical matrix gate switches for photonic switching , 1997 .

[67]  R.S. Tucker,et al.  Slow-light optical buffers: capabilities and fundamental limitations , 2005, Journal of Lightwave Technology.

[68]  J. Bowers,et al.  Integrated gate matrix switch for optical packet buffering , 2006, IEEE Photonics Technology Letters.

[69]  Arthur J. Lowery,et al.  Photonic packet switch using semiconductor optical amplifier gates , 1991 .

[70]  Thierry Zami,et al.  First demonstration of an asynchronous optical packet switching matrix prototype for multi-terabit-class routers/switches , 2001, Proceedings 27th European Conference on Optical Communication (Cat. No.01TH8551).

[71]  E. Towe,et al.  Scanning the issue - Special issue on optical interconnections for digital systems , 2000, Proc. IEEE.

[72]  H. Ishikawa,et al.  High-efficiency wavelength conversion using FWM in an SOA integrated DFB laser , 2000, IEEE Photonics Technology Letters.

[73]  M.E. Ali,et al.  Demonstration of a high-density parallel-WDM optical interconnect , 2004, The 17th Annual Meeting of the IEEELasers and Electro-Optics Society, 2004. LEOS 2004..

[74]  Hoi-Jun Yoo,et al.  A practical method to use eDRAM in the shared bus packet switch , 2002, Global Telecommunications Conference, 2002. GLOBECOM '02. IEEE.

[75]  Damon Wischik,et al.  Buffer requirements for high-speed routers , 2005 .

[76]  J. Goodman,et al.  Space division switches based on semiconductor optical amplifiers , 1992, IEEE Photonics Technology Letters.

[77]  H. Hamann,et al.  Active control of slow light on a chip with photonic crystal waveguides , 2005, Nature.

[78]  Hiroaki Harai,et al.  40 Gbit/s interface, optical code based photonic packet switch prototype , 2003, OFC 2003 Optical Fiber Communications Conference, 2003..

[79]  B.J. Eggleton,et al.  Slow gap soliton propagation excited by microchip Q-switched pulses , 2005, 2005 IEEE LEOS Annual Meeting Conference Proceedings.

[80]  Ludovic Noirie,et al.  1.28 Tbit/s throughput 8/spl times/8 optical switch based on arrays of gain-clamped semiconductor optical amplifier gates , 2000, Optical Fiber Communication Conference. Technical Digest Postconference Edition. Trends in Optics and Photonics Vol.37 (IEEE Cat. No. 00CH37079).

[81]  Jeff F. Young,et al.  Extrinsic optical scattering loss in photonic crystal waveguides: role of fabrication disorder and photon group velocity. , 2005, Physical review letters.