Multilayer Design. Grooming Layer + Optical Layer

Transcription

1 Multilayer Design Grooming Layer + Optical Layer Raghu Ranganathan, Office of CTO rraghu@ciena.com OFC 2008 Workshop Acknowledgements: Joe Berthold Loudon Blair Michael Frankel Lyndon Ong Harshad Sardesai Sashi Thiagarajan

2 Outline Challenges Issues Solutions 2

3 Challenges: Multi-layer traffic engineering NNI Transition from PoS to Ethernet L3+ Services NNI Transition from SDH to OTH OTN Packet Service Convergence MPLS ATM FR Ethernet IP /MPLS SONET /SDH 10GE GE Control Plane Circuit (sub-λ) Service Convergence L2 Ethernet Video (SDI) GE/ 10GE LAN PL STORAGE (FC) ESCON SONET/SDH Ethernet /SONET /SDH /OTH OTN SONET /SDH Control Plane Circuit (λ) Service Convergence 10G SONET/SDH 40G SONET/SDH 10GE / 100GE ODU-N OTN Agile WDM Control Plane Multiple Service Layers Multiple Switching Layers 3

4 Challenges: Network Architect s view Architecture: Multiple Service Layers (IP, Ethernet, PDH/SDH, Storage, Video) Traffic Profile: Static or Dynamic (holding time), SLA Network Connectivity: Point-Point or Multi-point (V)PN s Network Scope: Metro/National/Global and Single/Multiple providers Planning: Multiple Switching Layers (MPLS, Ethernet, SDH, OTH, WDM) Greenfield: New or overlay with circuit migration Brownfield: Selective node or network migration Operations: Sweat current assets Reduce Average Cost ($ / bit) : optimizing node, link, network Reduce Marginal Cost ( $ / bit) : scaling node, link, network Reduce Churn Rate ( subs / subs) : improving performance (QoS, QoE?) 4

5 Challenges: Equipment Architect s view Complex Switching (Multiple Data Planes) L0 with multi-degree WSS : multiple hops, multicast, protection, Signal quality L1 migration : SONET/SDH OTH ; Rings Mesh ; Protection Restoration L2 Ethernet: Point to Multipoint & Multipoint topologies Higher Intelligence (Control/Management Planes) Multi-layer & Multi-domain : discovery, signaling & routing protocols Management plane Interaction : path computation, on-demand network state Quality of Service : Latency, Jitter, Loss, Availability, Restoration Time Reliable Software Configuration : Embedded (online) vs Desktop Server (offline) Computation : Efficient algorithms (Run time vs Optimal Results) Consistency : Desktop Simulation vs Field Deployment (eg. restoration time) 5

6 Challenges: Complex Network Planning User Service Demands Bandwidth Quality, Latency Protection Abstracted Physical Layer Nodes/Links Path length/delay/relative cost Known limits (capacity, reach, etc ) Service Aggregation and Routing (Layer 1 / 2) Switching System hardware limitations Optical System hardware limitations Diverse routing and protection / SRLG Restoration mechanisms Services aggregated into wavelengths Possible Optimization Loopback May be owned by different carrier business units! Optical Transport (Layer 0) Planning / Deployment Separation of Metro / Regional / ULH Node transparency BOM, Pricing, Drawings, etc Deployment process 6

7 Issues: Network Partition Hierarchical Core Network Separate Core & Regional Mesh/Ring Multiple OAM/transport routing domains Regional Networks for intermediate aggregation 15 Super-PoPs ULH WDM Flat Core Network Collapsed Core/Regional Mesh Single OAM/transport routing domain Access directly aggregate to Metro/Core 100 Core-PoPs ULH WDM CORE CORE Core Gateway Region Gateway REGION Region Gateway Mesh Large Region REGION Ring Small Region Ring ACCESS Ring ACCESS 7

8 Issues: Layer 0 Node Partition Four optical transparency levels available: All-OOO: Degree-N transparent at all nodes Hi-OOO: Degree-2 transparent as much as possible Hi-OEO: Degree-2 transparent, But Degree (N>2) opaque All-OEO: Degree-N opaque at all nodes Degree-2 All-OOO Hi-OOO Hi-OEO All-OEO OADM OADM OADM Network Cost High traffic demand Low traffic demand Degree-3 WSS OADM All OEO All OOO Optical Transparency 8

9 Issues: Operation model vs Mesh networking Network database has Home route Home routes are for lifetime Revertive Maximize optical transparency Design Express paths Capacity x Distance, Gb/s.km 9,000,000 8,000,000 7,000,000 6,000,000 5,000,000 4,000,000 3,000,000 2,000,000 1,000,000 0 All Optical 1+1 Pan European Network: 1.4Tb/s All OEO 1+1 All OEO Shared Mesh 60% less Select OEO Shared Mesh 3500 Pan European Network: 1.4Tb/s Restoration capacity is temporary use Maximize bandwidth re-use Maximize bandwidth sharing Design Non-Express paths 10G termination count % less All Optical 1+1 All OEO 1+1 All OEO Shared Mesh 31% less Select OEO Shared Mesh Ref: Ranganathan et.al., ECOC

10 Issues: Layer 0 design (Metro vs. LH) Metro : small inter-node distance based on multi-node decisions Long-Haul : large inter-node distance based on individual span decisions 40 km 40 km 80 km 80 km Node 1 Node 2 Node 4 Node 1 Node 2 Node 4 DCM20 N1 to N4 DCM20 N1 to N4 & N1 to N3 Node 3 20 km DCM80 N1 to N2 DCM80 N2 to N3 Node 3 80 km DCM80 N2 to N4 40 km Node change: Terminal to ROADM? 40 km Node 6 Node 1 Node 2 Node 4 Node 7 DCM? N1 to N6 Node 3 20 km Network Growth Node 5 Static vs. Dynamic Lightpath 10

11 Issues: Physical Layer Convergence -- Maybe May be owned by different carrier business units! Metro Regional ULH 2.5 Gb/s SFP 10 Gb/s XFP CWDM DWDM 1 or 2 stage EDFA Sparse Disp Comp SONET Gb Ethernet Fibre Channel 10 Gb/s LH 40 Gb/s LH DWDM 2 stage EDFA Full Disp Comp SONET 10G Ethernet 10 or/ 40 Gb/s 100 Gb/s DWDM 2 or 3 stage EDFA Nonlin. Disp Comp SONET 10G Ethernet 100G Ethernet Some technologies are shared, but some are quite different 11

12 Ciena s Optical Transport Design Philosophy Transport layer needs to be Modular and Flexible Standard: Multi-sourced components drives cost & risk down Programmable: Dynamic traffic flows Help Carriers to improve average and marginal cost Greenfield: Introduction of next generation platforms/networks Better, Faster, Cheaper and, oh yes Integrated Brownfield: Evolution of installed base with improvements Flexible Port : Bit rate (2.5G 100G), Service (SONET/SDH OTN Ethernet FC) Flexible Node : Amplifier Traffic drop, Terminal OADM, Degree 2 Degree N Be aware of DESIGN PROCESS (i.e. tools) COMPLEXITY Legacy compatibility: network scaling optimized AROUND installed gear 12

13 Solutions: Multi-layer Design Tool (Example capabilities: Ciena s Core Director Designer) Intelligence: Control plane capabilities / simulation Scale, Scale, Scale 100+ nodes & 10,000+ circuits in one routing domain Routing and Signaling based Capacity Planning Mesh Survivability : multi-layer, restoration time, circuit priority Focus: Lowest cost capacity planning Re-groom existing circuits & Capacity for new circuits including TE Maximize switching at the cheapest layer (optical vs. tdm vs packet) Flexibility: User/Management interface End-to-End view of Circuit/Node/Network across domains Live Network Import Export to offline computing - Layer 0 WDM Model 13

14 Solutions: Layer 0 considerations Simplify Laptop based software for offline Layer 0 network design. Post-processing to get accurate BER calculations Automate Network partitioning, equipment placement, and regeneration 95% optimal solution within 5 minutes on a standard laptop computer Link to back end servers for inventory / pricing Bill of Materials (BOM) and Excel design reports Documentation for Greenfield and Brownfield deployment / turn-up 14

15 Conclusions Identified challenges, issues and some solutions Multi-layer design tools can help answer key questions Coupling between layers MPLS LSP s over OTN/WDM mesh network? Determine lower cost designs Sparse vs Dense Layer 0 topology? Complex Layer 0 but efficient Layer 1? 15