Reconfigurable Optical Networks using WSS based ROADMs Steven D. Robinson VP, Product Management  Five Essential Elements of the NG Optical Network... moving from static networks to dynamic networks  What does a ROADM do? Which type is better?  Key Technologies for 3 rd Generation ROADM systems  OEO vs. All Optical ROADMs  Digital ROADM Hybrid Solution  Intelligent Electrical & Optical Switching

Confidential 1  Reconfigurability  Simple, Flexible, Self Maintaining Systems  Pay as You Grow Scalability  Start with 1, grow by 1 Seamless upgrade to 100G (efficiently)  Aggregation & Sub- Switching  Integrated “ADM-on-a-blade”, High BW efficiency  Multi-Degree Operation  Both Optical & Electrical Multi-degree Options  Automated Network Planning  One time Node Engineering, GMPLS Control and Management Systems Plane & True “Point-and-Click” Provisioning Five Essential Elements of Next Generation Optical Networks ROADM OPM OPMOPM Mux ADM West East Design Networks in Minutes Up to 16 degrees

Confidential 2 What is a ROADM? DROPs ADDs ROADM Module OPMOPM Key attributes of ROADM Module  Fully Flexible, Remotely Reconfigurable Optical Add Drop  Automatic power equalization on inputs, outputs, adds, drops  Optical Power Monitoring (OPM) of all channels Reconfigurable Optical Add/Drop Multiplexer (ROADM) Key benefits of ROADM Module  Elimination of the OEO “Pass-through” tax   Scaleable Bandwidth ( Start with 1, grow by 1 )  Single Wavelength Granularity – No stranded bandwidth  Fully Automated Optical Layer

Confidential 3 WDM Optical Transport Technology Options Fixed Port ROADM FOADM Multi-Degree WSS ROADM with colorless ports Fully Flexible Multi-degree ROADM Per Optical Swit ch Multi-port Mux/Demux OPM Drops OPMOPM Multi-Degree WSS with fixed filters Fixed drops OPM Per Optica l Switc h Multi-port Mux/Demux OPM Fixed Adds 2 Degree ROADM Blocker/IPLC with fixed filters OPM Splitter / Drop filte rs Add Filters/ Combiner OPMOPM WB Module OEO Regen (Point-to-point DWDM)

Confidential 4 Which ROADM Technology is best? Full Flexible, WSS based ROADMs Wavelength Selective Switch (WSS) ROADM:  Utilizes a single element to multiplex AND demux all express and all add/drop wavelengths  Contains a built-in Optical Switch which can direct/select one or more wavelengths to/from any port  Provides Automated, per channel equalization on all wavelengths  Typically includes full Optical Power Monitoring on all wavelengths  Can be configured for truly colorless ports for widely tunable lasers & dynamic wavelength management  Can be modular (low first in costs) or fully installed on day one Key * Manages all wavelengths Features:* Lower system cost * No OEO Pass-thru tax * Fully Flexible Ports enable:  Any wavelength to any port  Supports Tunable lasers  Dynamic Management  Jumper-less provisioning * Multiple wavelengths/ drop port  Mesh node capability  Ring interconnection MP-WSS Flexible Drops Flexible Adds WSS       OPMOPM ROADM MODULE

Confidential 5 Key Technologies used in Core Reconfigurable Networks Fully Flexible WSS ROADMs ROADM Systems provide much more than just Wavelength Reconfigurability They provide a total “Agile Optical Network” Solution Integrated Platforms Rapid Automated Network Planning Cross Optical Switch w/ Integrated. Transport GMPLS Control Plane and End-to-End Management Widely Tunable Lasers Fully Automated Optical Layer Hot- Pluggable SFPs & XFPs Multi-Service ADM-on-a-blade Ethernet Networking True Point-and-click Planning & Provisioning AGC / Transient Controlled Optical Amplifiers (OAs) Integrated Optical Cabling Flexible, Transparent Optical Interfaces

Confidential 6 Why do customers like “All optical” Source  OEO becomes more expensive as the node count goes up (# Regens x # nodes)  OEO becomes more expensive as the number of wavelengths increases (# WL x # Regens x #nodes)  Use of Analog Optical Amplifiers lowers cost – unless you need to drop traffic All OEO or “Digital Transport”: At least 380 Transponders ILA All Optical ROADM : 42 Transponders ILA

Confidential 7 OEO or ROADM Which is the better choice? Decision depends on:  Bit Rate; Number of Wavelengths  Topology & Traffic Patterns  Switching Need ( which determines # of pass-thrus vs # of drops)  Size (# nodes and span length)  Amplify? Regen?  Total Cost of Ownership (OPEX vs. CAPEX) ROADM Gb/s Number of Pass-Thru Channels Bit Rate 10 Gb/s 2.5 Gb/s OEO ROADM ROADM

Confidential 8 Integrated OEO (Digital Transport) Multi-Service & Investment Protection Issues Network Bandwidth Efficiency 4 x 10G 10 x 10G Integrated Tx OEO Regen Integrated Rx Integrated 10G OEO:  Optimized for 10G client transmission  Other services require muxing or inverse muxing (no transparent transmission)  Support for native 40G or 100G will require ripping out OEO fabric

Confidential 9 2.5G Per WL OEO Switch 10G 40G 100G Multi-Degree OEO Switching Multi-degree ROADM or OEO? Why be forced to choose? All Optical ROADM Advantages:  Fully Bit Rate Transparent 1G  10G  100G  Per wavelength Scaleable 1  2   Lower Power  Fully Automated Optical Layer  Low Pass-thru costs OEO Advantages:  Sub-Wavelength Switching  Potentially Lower Terminal Costs (at full capacity)  Simpler Optical Engineering  Simpler Multi-Degree Operation Multi-Degree ROADM Switch Digital ROADM Node

Confidential 10 Digital ROADM Hybrid Node Lowest Overall Cost & Flexibility Digital ROADM Node  Topology Agnostic  Traffic Pattern Agnostic  Bit Rate Agnostic  Simpler Optical Engineering  Simpler Multi-Degree Operation  Lower overall cost solution Per WL OEO Switch Multi-Degree All Optical ROADM Multi-Degree Digital Switching 2.5G 10G 40G 100G All Optical Spur All Optical ROADM Maintain manageable regions of transparency TR

Confidential 11 Intelligent Optical & Electrical Switching WSS ROADM (Optical Switch) Add 6 GbE Drop/Add 1 GbE Electrical ADM Switching Options: Pass Thru Entire Wavelength Electrically Add/Drop on a per Service Basis Optical Drop Wavelength Optically Add/Drop Entire Wavelength Transponder with Electrical ADM Switch Mux ADM Optically Add/Drop Multiple Wavelengths (Multi-degree) Add/Drop Multiple Services/Wavelengths for Cross Wavelength Grooming & Multi-degree Switching Cross-WL Optical Switch with integrated WDM

Confidential 12 ROADM Networks Summary  Customers have recognized that low OPEX is now just as important as the lowest CAPEX  ROADM Modules are just one part of realizing the Next Generation Agile Optical Network  Other technologies such as automated planning tools, widely tunable lasers, optical backplanes, Pluggables, and GMPLS can dramatically simplify planning, operation & management  Selection of the right kind of ROADM is crucial to realizing these savings (Colorless Port, modular, WSS based ROADMs are the best choice)  These systems must be designed from the ground up to realize their full potential (Bolt-on ROADMs don’t work)  Digital ROADM Hybrid Solution may offer the best flexibility and lowest overall cost MP-WSS OPMOPM Flexible Drops Flexible Adds WSS 2.5G 10G 40G 100G