Constraints in multi-layer optimization for IP traffic over optical WDM networks. Detlef Stoll. OFC 2008, San Diego CA February 24, 2008

Transcription

1 Constraints in multi-layer optimization for IP traffic over optical WDM networks Detlef Stoll OFC 2008, San Diego CA February 24, 2008

2 Workshop topics Goals and guidelines for cost optimization in multi-layer optical networks Network example: Discussion of three realization options Integration of multi-layer cost optimizing algorithms into optical network planning tools 2 Nokia Siemens Networks

3 Cost drivers IP Routers CAPEX relation per Gbps 100% Layer 2 switches 5 50% average: 20% Optical network elements around 5% 3 Nokia Siemens Networks

4 Traffic through IP routers Network border IP router Port 7 Port 8 From/to other routers in the same network Port 1 Port 2 Port 3 Port 4 Port 5 Port 6 To/from other routers in the same network Extracted traffic ok, this traffic really needs IP routing Forwarded traffic (in the same network) Partly forwarded, partly extracted off-load this traffic! try to keep both separated! 4 Nokia Siemens Networks

5 Optimization guidelines in multi-layer networks Simple cost optimization strategy: Make all IP routers fully meshed! Soft rules: Avoid IP router hopping! Off-load IP routers from traffic aggregation! Fill up optical channels a good as possible! 5 Nokia Siemens Networks

6 Network elements and their added value IP Routers CAPEX relation per Gbps 100% Traffic processing on a detailed level Layer 2 switches Traffic grooming for bypassing IP routers Combining data streams for filling optical channels 20% Optical network elements High capacity transmission pipes Full mesh connectivity even in non-mesh networks 5% 6 Nokia Siemens Networks

7 Nokia Siemens Networks Realization Examples

8 Situation: Five IP routers in a WDM ring Topology: Ring 8 Nokia Siemens Networks

9 Situation: Five IP routers in a WDM ring Topology: Ring Traffic pattern: Full mesh Each router sends the same traffic volume to each other router. 9 Nokia Siemens Networks

10 Option 1: Forwarding IP traffic over large pipes OADM Checking the optimization rules: Avoid router hopping Off-load IP routers from traffic grooming Fill up optical channels a good as possible 10 Nokia Siemens Networks

11 Option 2: Direct interconnection via WDM channels Checking the optimization rules: Avoid router hopping Off-load IP routers from traffic grooming Fill up optical channels a good as possible 11 Nokia Siemens Networks

12 Option 3: Layer 2 switching Layer 2 switches Checking the optimization rules: Avoid router hopping Off-load IP routers from traffic grooming Fill up optical channels a good as possible 12 Nokia Siemens Networks

13 Conclusions Connecting all IP routers fully meshed yields significant CAPEX reduction potential. (Simulation results have shown reductions of about 20% typically.) WDM allows for fully meshed traffic in physical non-mesh topologies. The minimum cost solution varies for different network scenarios (Metro, Regio, backbone...). (cost relation: IP routing L2 switching WDM technology) Integrated planning of IP and optical networks Tool based multi-layer optimization 13 Nokia Siemens Networks

14 Multi-layer optimization tools Nokia Siemens Networks

15 Classical optimization problem Multi-layer optimization is a multi-dimensional optimization problem, defining a multi-dimensional operation range, identifying a cost-minimal operation point described by many parameters. 15 Nokia Siemens Networks

16 Integration into optical network planning tools SURPASS TransNet Optical Network Planning Tool Entering Network Topology & Traffic Matrix Traffic Grooming Optical Link Design Commissioning & Installation Traffic Routing Traffic Aggregation Cost Tables Optical Channel Carrier Assignment Multi-layer optimization 16 Nokia Siemens Networks

17 Thank you for your participation! Nokia Siemens Networks