EFFICIENT ROUTING FOR HYBRID OPTICAL-CDMA AND WDM ALL-OPTICAL NETWORKS

1. EFFICIENT ROUTING FOR HYBRID OPTICAL-CDMA AND WDM ALL-OPTICAL NETWORKS Mehdi Shadaram and Paul Cotae University of Texas at San Antonio San Antonio, TX 78249 and Ahmed Musa, Virgilio Gonzalez, and John Medrano University of Texas at El Paso El Paso, TX 79968 IEEE MILCOM Conference Washington, D.C. October 23-25, 2006 ECE Department, Photonics Research Laboratory

2. OUTLINE • Introduction (Why?) • Backbone Network- Optical-Optical-Optical (OOO) - Optical-Electrical-Optical (OEO) • Routing Benefits and Disadvantages • Proposed Routing Algorithm • Routing (Setup Optimal Lightpath) Steps • Routing Implementation Using Flooding Mechanism • Example • Conclusions ECE Department, Photonics Research Laboratory

3. INTRODUCTION • A high demand for higher capacities because of • Multimedia services • Video conferences • Internet • Environmental Remote Sensing • Medical Imaging • Approaches to make the transmission medium with a scalable bandwidth (BW) capacity • Install more fiber (costly) • Exploit the BW of existing fiber using higher data rates and multiplexing techniques such as • Wavelength Division Multiplexing (WDM) • Time Division Multiplexing (TDM) • Code Division Multiplexing (CDM) ECE Department, Photonics Research Laboratory

4. ALL OPTICAL NETWORKS • Advantages • Solve the electronic equipment bottleneck • Exploit the existing network • Disadvantages Photonic NW is a complex system ( a large number of different functions must cooperate for a network such as • transmission • Routing and Switching • Control and management • etc. ECE Department, Photonics Research Laboratory

5. IMPAIRMENTS ECE Department, Photonics Research Laboratory

6. ROUTING ALGORITHM FLOW DIAGRAM ECE Department, Photonics Research Laboratory

7. ROUTING PROCEDURE Proposed Routing Algorithm • Use Optical CDM and WDM to label the optical signal • Take into account the physical impairments exist in the NW • Set up the lightpath based on the minimum cost from ingress to egress node. Routing (Setup Optimal Lightpath) Steps First Step : Calculate the fiber metrics Second Step : Calculate switch metrics Third Step : Apply Viterbi algorithm on each close loop from the source to destination to select the minimum metric ECE Department, Photonics Research Laboratory

8. I/P Metric O/P Metric Link merits (L) :- Attenuation  Dispersion D Where , and  is a function of Attenuation  and Dispersion D FIBER METRICS ECE Department, Photonics Research Laboratory

9. SWITCH METRICS CALCULATION ECE Department, Photonics Research Laboratory

10. SWITCH METRIC CALCULATION ECE Department, Photonics Research Laboratory

11. SWITCH STRUCTURE ECE Department, Photonics Research Laboratory

12. FIBER METRIC CACULATION ECE Department, Photonics Research Laboratory

13. NETWORK UNDER INVESTIGATION ECE Department, Photonics Research Laboratory

14. BLOCKING PROBABILITY c represents the bisectional bandwidth (BSBW) a is the traffic load in Erlang ECE Department, Photonics Research Laboratory

15. TRAFFIC PARAMETERS ECE Department, Photonics Research Laboratory

16. SYSTEM PARAMETERS OF THE NETWORK ECE Department, Photonics Research Laboratory

17. BLOCKING PROBABILITY WITH/WITHOUT CONSTRAINT SWITCH ECE Department, Photonics Research Laboratory

18. AVERAGE COST/CONNECTION ECE Department, Photonics Research Laboratory

19. SUMMARY • A fundamental understanding of the basic routing techniques and the factors that influence their behavior is critical in designing and selecting appropriate routing strategies for a network • To alleviate the routing complexity, different optimization methodologies are proposed • Better utilization of the network resources can be achieved when the impairments in the network are taken into consideration in the routing algorithm ECE Department, Photonics Research Laboratory