What s Next for Optical Networking

1. What�s Next for Optical Networking OFC Market Watch March 10th 2011 Los Angeles, CA

2. Agenda �What�s next�, not �what we�ve done� (Andrew Schmitt) Next Generation ROADM Architecture Flexible Bandwidth Grid Concept Future Bit Rate Options Summary

3. Industry First 100G Deployment 

4. What�s Next?

5. Basic ROADM Structure Architecture: 4-Degree ROADM with colored add/drop Wavelength switching to route wavelengths between fiber directions Fixed wavelength multiplexer in add/drop structure Used for P-OTP metropolitan networks Pros: 100% channel add/drop supported for each direction Cons: Each add/drop port has fixed color Separate add/drop structure for each direction Transponder color and fiber direction hardwired when connected to a particular add/drop port

6. Architecture: 4-Degree ROADM with colorless add/drop Wavelength switching to route wavelengths between fiber directions Tunable wavelength selection in add/drop structure Pros: 100% channel add/drop support for each direction Each add/drop port can be assigned any color Cons: Separate add/drop structure for each direction Transponder fiber direction hardwired when connected to particular add/drop direction Each add/drop structure cannot have transponders with the same wavelength Colorless Architecture

7. Architecture: 4-Degree ROADM with colorless and directionless add/drop Wavelength switching to route wavelengths between fiber directions Add/Drop wavelength routing Tunable wavelength selection in add/drop structure Pros: 100% channel add/drop support for each direction Each add/drop port can be assigned any color Add/drop wavelength can be routed to any direction Cons: Each add/drop structure cannot have multiple transponders with same wavelength Colorless & Directionless Architecture

8. Architecture: 4-Degree ROADM with unrestricted add/drop Wavelength switching to route wavelengths between fiber directions Add/drop wavelength routing Tunable wavelength selection in add/drop structure Pros: Any add/drop port can go any direction with any wavelength Each add/drop port can be assigned any color Add/drop wavelength can be routed to any direction No restrictions on color re-use in add/drop structure Cons: Most complex implementation Colorless, Directionless, & Contentionless

9. Current generation WDM systems supported 10G, 40G and now 100G in service upgrades Future systems will be expected to support in service upgrades to at least 1T / channel Given the current view, more bandwidth is the only way to achieve this w/o paying a significant reach penalty due to OSNR requirements Flexible Bandwidth Grid

10. Fully Flexible Layer 1 Network Colorless/Directionless/Contentionless ROADM node with flexible grid Colorless wavelength add/drop with directional routing Choose the bandwidth of the light path to match the service bitrate Use multiple copies of the same color wavelength on the add/drop structure

11. Summary Flexible bandwidth grid architectures are required for upgradability Colorless, directionless & contentionless are required for flexibility Integration is required to improve cost and network reliability However � the jury is still out on what comes after 100G (imho) Good news is we don�t need to (and probably shouldn�t) decide today Spectral efficiency, cost savings and performance are the real drivers