1. November 18, 2005 1 Traffic Grooming in Optical WDM Networks Presented by : Md. Shamsul Wazed University of Windsor

2. November 18, 20052 Abstract

3. 3 Abstract  Requested bandwidth of a traffic stream can be lower than the wavelength capacity  Grooming the low-speed traffic streams onto high capacity optical channels  Objective :  Improve network throughput  Minimizing network cost

4. November 18, 20054 Abstract  Most previous work on traffic grooming in the ring network topology  Traffic grooming is an important problem for Wavelength Division Multiplexing (WDM) network  Recent research works with a mathematical formulation will be discussed here

5. November 18, 20055 Outline  IntroductionIntroduction  Multiplexing TechniquesMultiplexing Techniques  Minimizing Network ResourcesMinimizing Network Resources  Grooming Switch ArchitectureGrooming Switch Architecture  Grooming with ProtectionGrooming with Protection  Mathematical (ILP) FormulationMathematical (ILP) Formulation  ConclusionConclusion

6. November 18, 20056 Introduction

7. 7 Introduction  3 generation of networks :  Choice of optical fiber : High bandwidthHigh bandwidth, low error rate, reliability High bandwidth  1 st generation network – copper wire based  2 nd generation network – mix of copper wire and optical fiber (SONET, WDM, SDH etc)  3 rd generation network – all-optical based

8. November 18, 20058 Objective of Traffic Grooming :  To combine low-speed traffic streams onto high-capacity wavelengths  Improve bandwidth utilization  Optimize network throughput  Minimize the network cost (transmitter, receiver, fiber link, OXC, ADM, amplifier, wavelength converter etc) (transmitter, receiver, fiber link, OXC, ADM, amplifier, wavelength converter etc)OXCADMOXCADM Introduction

9. November 18, 20059 Multiplexing Techniques

10. November 18, 200510 Multiplexing Techniques  Different multiplexing techniques used in traffic grooming :  Space-division multiplexing (SDM) - bundling a set of fibers into a single cable, or using several cables within a network link  Frequency-division multiplexing (FDM) – a given fiber to carry traffic on many distinct wavelengths.  Time-division multiplexing (TDM) – multiple signals can share a given wavelength if they are non-overlapping in time.

11. November 18, 200511  6 node network  Wavelength Capacity OC-48  3 connection requests OC-12 at (0,2) OC-12 at (2,4) OC-3 at (0,4)  2 lightpaths 1 carrying Connection 3 Multiplexing Techniques 1 logical communication route between two nodes established if wavelength is available

12. November 18, 200512 Minimizing Network Resources

13. November 18, 200513 Minimizing Network Resources  Network resources must be used efficiently  Electronic ADMs can be saved and network cost will be reduced  WDM add/drop multiplexers (WADMs) is capable to drop or add wavelength  Depends upon designing of Network topology

14. November 18, 200514 Minimizing Network Resources Minimizing Network Resources SONET/WDM ring (Ungroomed)

15. November 18, 200515 Minimizing Network Resources SONET/WDM ring (Groomed)

16. November 18, 200516 Grooming Switch Architecture

17. November 18, 200517 Grooming Switch Architecture Grooming Switch Architecture  Static traffic grooming can be measured by fixed traffic matrices traffic matricestraffic matrices  WADM allows wavelength to either be dropped and electronically processed at the node or optically bypass  Node architecture for a WDM mesh network has the static traffic grooming capability

18. November 18, 200518 Grooming Switch Architecture Grooming Switch Architecture

19. November 18, 200519 Grooming with Protection

20. November 18, 200520 Grooming with Protection  Connection also requires protection from network failure  A single failure may affect a large volume of traffic  Working path carrying traffic at normal operation  Backup path re-routed the traffic after path failure

21. November 18, 200521 Grooming with Protection

22. November 18, 200522 Mathematical (ILP) Formulation

23. November 18, 200523 Mathematical (ILP) Formulation  A six-node multi-hop network  Capacity (C) of each wavelength OC-48 OC-48  3 types of connection request (OC-1, OC-3, and OC-12)  3 Traffic matrices generated randomly Traffic matricesTraffic matrices  Total traffic demand ≤ OC-988  A six-node network six-node networksix-node network  In our example, we consider :

24. November 18, 200524 Mathematical (ILP) Formulation  At most one fiber link between each node pair.  Nodes do not have wavelength conversion capability (i.e. no wavelength converter). wavelength converterwavelength converter  The transceivers in a network node are tunable to any wavelength on the fiber.  Each node has unlimited multiplexing / demultiplexing capability  Assumptions :  A six-node network six-node networksix-node network

25. November 18, 200525 Mathematical (ILP) Formulation  Maximize the total successfully-routed low- speed traffic, i.e.  A six-node network six-node networksix-node network  ILP formulation :  Allowed low-speed stream, y {1,3,12,48}  = 1 if success, 0 otherwise  t {1, …,T y,s,d } , Lightpaths cannot exceed wavelength capacity

26. November 18, 200526 Mathematical (ILP) Formulation  A six-node network six-node networksix-node network  Numerical Result 1: Multi-hop ThroughputLightpath # T=3, W=374.7% (OC-78)18 T=4, W=393.8% (OC-927)24 T=5, W=397.9% (OC-967)28 T=7, W=397.9% (OC-967)28 T=3, W=474.7% (OC-738)18 T=4, W=494.4% (OC-933)24 T=5, W=4100% (OC-988)29 where, T is number of Transceivers and W is number of wavelength

27. November 18, 200527 Mathematical (ILP) Formulation  A six-node network six-node networksix-node network  Numerical Result 2: Node 0Node 1Node 2Node 3Node 4Node 5 Node 002 (70%)0 (100%)1 (89%)1 (100%) Node 11 (100%)0 2 (100%)1 (100%)0 Node 21 (100%)1 (95%)01 (100%)2 (100%)1 (70%) Node 32 (100%)1 (100%) 00 Node 41 (100%) 0001 (91%) Node 50 (100%)02 (98%)1 (100%) 0 Virtual Topology and Lightpath Utilization (T=5, W= 3)

28. November 18, 200528 Conclusion

29. November 18, 200529 Conclusion  Recent research and development in traffic grooming in WDM network reviewed  Objective – multiplexing low-speed traffic streams on to high-capacity optical channels  Optimum utilization of bandwidth, lower the network resource cost  Node architecture, Path/Link Protection  Illustrated an example by using ILP formulation  Many significant results of practical importance are forthcoming

30. November 18, 200530 References [1]R. S. Barr, M. S. Kingsley and R. A. Patterson, “Grooming Telecommunication Networks : Optimization Models and Methods,” Technical Report 05-EMIS-03, June 2005. [2]K. Zhu and B. Mukherjee, “Traffic Grooming in an Optical WDM Mesh Networks,” IEEE Journal Selected Areas in Communications, Vol. 20, No. 1, January 2002. [3]K. Zhu and B. Mukherjee, “A Review of Traffic Grooming in WDM Optical Networks : Architectures and Challenges,” Optical Networks Magazine, Vol. 4, No. 2, March/April 2003, pp 55-64. [4]E. Modiano and P. Lin, “Traffic Grooming in WDM Networks,” IEEE Communication Magazine, Vol. 39, No. 6, July 2001, pp 124-129. [5]B. Mukherjee, C (Sam) Ou, H. Zhu, K. Zhu, N. Singhal and S. Yao, “Traffic Grooming in Mesh Optical Networks,” IEEE Optical Fiber Communication (OFC) Conference’04, March 2004. [6]W. Yao and B. Ramamurthy, “Survivable Traffic Grooming With Path Protection at the Connection Level in WDM Mesh Networks”, Journal of Lightwave Technology, October 2005, Vol. 23, No. 10, pp. 2846-2853

31. November 18, 200531  Slide outline Slide outline Slide outline

32. November 18, 200532 Optical level Bit rate OC-152 Mbps OC-3156 Mbps OC-12622 Mbps OC-482,488 Mbps OC-1929,953 Mbps OC-76839,813 Mbps (in near future) [ OC-nn * 51.84 Mbps] Transmission Speed Optical level Bit rate OC-152 Mbps OC-3156 Mbps OC-12622 Mbps OC-482,488 Mbps OC-1929,953 Mbps OC-76839,813 Mbps (in near future) [ OC-nn * 51.84 Mbps]  Back to Introduction Introduction  Back to ILP Formulation ILP FormulationILP Formulation

33. November 18, 200533 Optical Cross-Connect (OXC)  Back to Introduction Introduction

34. November 18, 200534 Optical Add-Drop Multiplexer (ADM)  Back to Introduction Introduction

35. November 18, 200535 Sample Traffic Matrix of OC-3 Connection Request  Back to Switch Architecture Switch ArchitectureSwitch Architecture  Back to ILP Formulation ILP FormulationILP Formulation

36. November 18, 200536 Wavelength Converter (WC)  Back to ILP Formulation ILP FormulationILP Formulation

37. November 18, 200537 Physical Topology of a Six-Node Network  Back to ILP Formulation ILP FormulationILP Formulation