1 / 12

Optical Networks Optical Circuit Switching (OCS)

Optical Networks Optical Circuit Switching (OCS). Cheyns: Optical packet switched... AWG. Results from the EU IST-project STOLAS Optical packet/burst switches requires fast (ns) reconfigurable switching matrixes. AWG with fast tunable wavelength converters is an alternative. .

kay
Télécharger la présentation

Optical Networks Optical Circuit Switching (OCS)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Optical NetworksOptical Circuit Switching (OCS)

  2. Cheyns: Optical packet switched... AWG • Results from the EU IST-project STOLAS • Optical packet/burst switches requires fast (ns) reconfigurable switching matrixes. • AWG with fast tunable wavelength converters is an alternative.

  3. Arrayed waveguide Grating • 1 X N or N X N coupler spreads the light in N waveguides with different lengths • Waveguides are merged and create interference • Each wavelength will constructively recombine at only one given output port and cancel out on the others, due to the phase difference

  4. AWG switching principle • Cyclic • F fibres , W wavelengths • Same output for lj as for lj + WDl • Table: Given input port and wavelength, the output port is found from the table.

  5. Simple AWG node architecture • Internal blocking when two inputs with the same l to the same fibre • No conversion at output • Conversion range at input: l0 to l3 required • Limits which output port the input can be connected to => blocking • Internal blocking may be relaxed by smart choices of output wavelengths for converters and many wavelengths. l0

  6. No blocking version • Input converters must be able to convert to seven different wavelength converters: Larger wavelength range. • Fixed wavelength at output converters for multiplexing • Only one wavelength for each output. • Potential problems with scaling, size of AWG.

  7. Using smaller AWGs • Future networks have many wavelengths: Scalability • Simple to add an extra input: Add extra input on optical coupler (cheap). • AWG with W input/output ports • Two inputs which is combined can not be converted to the same l: Contention • Couplers at output ports • Same blocking properties as the first design. (Same l setting) • Scales with W rather than F*W (first design)

  8. Small AWG, many internal wavelengths • Nonblocking • F*W internal wavelengths • 2F multiplexers with size F*W • Several wavelengths on each output port. • W*F2 TWC’s with conversion grade W • Tunable converters at output

  9. Alternative solution (multiport): • Reduced size of muxes and number of converters • Still nonblocking • Still FW internal wavelengths • FW fixed output wavelength converters • W demultiplexers, but F smaller/cheaper Foretrukket!

  10. Optical Pan European Network (The OPEN project) • Broadcast & Select switching architecture, non-blocking • Multicast is simple • Scaling a problem, attenuation in couplers. All inputs available for all outputs

  11. Norway-Denmark field trial

  12. Field trial • OXC, wavelength conversion, Optical Add/drop • Mix of SDH and Pseudo Random Bit sequences (PRBS) • Different fibre types, Dispersion Compensating Fiber (DCF), amplifiers, transponders

More Related