Physical Layer Components, Architectures and Trends for Agile Photonic Layer Mesh NetworkingBrandon C. Collings

JDSU Optical Networks Research LabRobbinsville, NJ 08691 USA

ECOC, Sept. 23, 2009

Paper 6.7.2

© 2009 JDSU. All rights reserved. 2

Outline

Advantages of “Static” ROADM Optical Mesh Networks

The WSS and Current “Static” Mesh Node Architectures

Applications of “Dynamic” Optical Mesh Networks

Node Architectures for “Dynamic” Mesh Networks– Colorless ports

– Directionless ports

© 2009 JDSU. All rights reserved. 3

Advantages of Static ROADM Optical Mesh Networks

Eliminate OEO at network junctions– Considerable cost, complexity and maintenance savings

Flexible wavelength topology enables efficient capacity growth– Most efficient routes can be selected

– Extends lifetime of system

Add new connectivity via unused degrees as needed– Parallel spans, spurs, extensions, ring interconnects

– Maintains in-situ HW and management

© 2009 JDSU. All rights reserved. 4

The Wavelength Selective Switch (WSS)1xN port device

Independently routes each channel to one of N ports

Attenuate and block channels independently

Optically bi-directional

wavelengthWavelength

SelectiveSwitch(WSS) N

ports

© 2009 JDSU. All rights reserved. 5

WEST

Typical Reconfigurable Ring Node Architecture

WSS selects outbound wavelength traffic

AWG’s used to multiplex and demultiplex locally added and dropped channels – “Colored” add/drop ports

Tx Tx Tx Tx

AWG

Tx

WSS

Power

Splitter

Rx

Rx

Rx

Rx

AWG

Rx

TxTxTxTx

AWG

Tx

WSS

Pow

er

Split

ter

Rx

Rx

Rx

Rx

AWG

Rx

EAST

© 2009 JDSU. All rights reserved. 6

WEST

Typical Reconfigurable Mesh Node Architecture

Tx Tx Tx TxAWG

Tx

WSS

Power

Splitter

Rx

Rx

Rx

Rx

AWG

Rx

TxTxTxTxA

WG

Tx

WSSPower Splitter

RxRxRxRx A

WG

Rx

TxTxTxTx

AWG

Tx

WSS

Pow

er

Split

ter

Rx

Rx

Rx

Rx

AWG

Rx

TxTxTxTx

AW

G

Tx

WSSPower SplitterRx

RxRxRx

AW

G

Rx

NORTH

SOUTH

EAST

© 2009 JDSU. All rights reserved. 7

Dynamic Optical Mesh Network ApplicationsPhotonic layer restoration

– Restoration complements higher layer protection to increase overall availability

– Relaxes urgency to repair fiber (OpEx argument and reliability increase)• Some locations have limited access (disaster zone, subways, remote locations, undersea

festoons)

– Reduces excess capacity allocated for protection contingencies (CapEx argument)

Load Balancing– Move existing traffic to relieve emerging bottlenecks

Maintenance switching– In-service wavelength bridge-and-roll around planned maintenance

© 2009 JDSU. All rights reserved. 8

Dynamic Optical Mesh Network ApplicationsPhotonic layer restoration

– Restoration complements higher layer protection to increase overall availability

– Relaxes urgency to repair fiber (OpEx argument and reliability increase)• Some locations have limited access (disaster zone, subways, remote locations, undersea

festoons)

– Reduces excess capacity allocated for protection contingencies (CapEx argument)

Load Balancing– Move existing traffic to relieve emerging bottlenecks

Maintenance switching– In-service wavelength bridge-and-roll around planned maintenance

© 2009 JDSU. All rights reserved. 9

Dynamic Optical Mesh Network ApplicationsPhotonic layer restoration

– Restoration complements higher layer protection to increase overall availability

– Relaxes urgency to repair fiber (OpEx argument and reliability increase)• Some locations have limited access (disaster zone, subways, remote locations, undersea

festoons)

– Reduces excess capacity allocated for protection contingencies (CapEx argument)

Load Balancing– Move existing traffic to relieve emerging bottlenecks

Maintenance switching– Move traffic away from area of planned maintenance

© 2009 JDSU. All rights reserved. 10

Dynamic Optical Mesh Switching Requires…

Optical network level features:– Colorless add/drop ports

– Directionless add/drop ports

© 2009 JDSU. All rights reserved. 11

WEST

Colorless Add/Drop Ports

Replace mux/demux AWGs with WSS’s– Wavelength assigned to each port is provisionable

Applications– Fewer physical ports present simplifying faceplate

– Operating wavelength can be remotely modified

Tx Tx Tx Tx

WSS

Tx

WSS

Power

Splitter

Rx

Rx

Rx

Rx

WSS

Rx

TxTxTxTx

WSS

Tx

WSS

Pow

er

Split

ter

Rx

Rx

Rx

Rx

WSS

Rx

EAST

© 2009 JDSU. All rights reserved. 12

Directionless Add/Drop Ports

Rx

Rx

Rx

WS

S

WE

ST

PS

WS

S

NO

RTHP

S

WSSPS

WSSPS

Tx Tx Tx Rx

Rx

Rx

WSSPS

WSSPS

Tx Tx Tx

WS

S

SO

UTH

PS

WS

S EA

STP

S

Add/Drop Bank 1

Add/Drop Bank 2

1xN

1xM

© 2009 JDSU. All rights reserved. 13

Directionless Add/Drop Ports: NxM WSS

WS

S

WE

ST

PS

WS

S

NO

RTHP

SW

SS

SO

UTH

PS

WS

S EA

STP

S

WSS WSS

Add/Drop Bank 1

Add/Drop Bank 2

NxMWSS WSS

Rx

Rx

Rx

Tx Tx Tx Rx

Rx

Rx

Tx Tx Tx

© 2009 JDSU. All rights reserved. 14

Summary

Past and Present– Optical mesh networks currently being deployed for efficient

operations and capacity growth

Present– Applications leveraging the dynamic capabilities of the mesh

network are emerging

Future– Mesh networks with colorless and directionless add/drop ports

– Network optimization must become multi-layer • Leveraging the strengths of each layer

– Develop multi-layer management systems which can execute this optimization automatically and seamlessly

Thank You!Brandon C. Collings

JDSU Optical Networks Research LabRobbinsville, NJ 08691 USA