VD-C JP-B JP-G Joint plenary meeting Barcelona, 26 February 2007

1. VD-C JP-B JP-G Joint plenary meeting Barcelona, 26 February 2007

2. WP-VD-C Optical Core NetworksJoint Activities

3. Activity 1Congestion Resolution in Optical Burst/Packet Switching with Limited Wavelength Conversion DEIS-UNIBO - Optinova

4. W number of wavelengths B number of delays sij S potential scheduling instants |S| = WB is the “capacity” of the algorithm How to compare Scheduling strategies W = 4, B = 5  |S| = 20 W = 10, B = 2  |S| = 20 • Is |S| enough to characterize a WDS strategy? • Is it better to bet on W or B?

5. Full range VS limited range conversion • Keep the same number of actual scheduling point • |S'| = 64 • LRWC better than FWC when trading wavelength conversion capability with delays

6. Activity 4Advanced Connectivity Service Provisioning in GMPLS Networks SSSUP - FUB - KTH Piero Castoldi (castoldi@sssup.it) Luca Rea (lrea@fub.it) Lena Wosinska (lena@it.kth.se)

7. Motivation and scope • Connectivity request issued by qualified applications (e.g., Broadcast TV, Grid, Storage, Digital Cinema) may benefit from the QoS-enabled services provided by GMPLS-based transport network • The GMPLS/OIF User to Network Interface (UNI) is not conceived for being directly invoked by applications • Introduction of the Service Platform (SPF) to for the provisioning of on-demand GMPLS connectivity services (e.g., LSP-MPLS, VPN L2, VPN L3 ) to applications • The SPF provides Service Abstraction and Resource Virtualization capabilities

8. The SPF Architecture • An application requests network service with specific parameters • There is a deep syntactic and semantic differences between Application and Network domains • The SPF transfer a network service request issued by an application into a set of UNI directives to the GMPLS CP Application Level Application Entity USI Service Level Service Platform (SPF) UNI UNI Network Level Edge Node CP Edge Node CP (G)MPLS Network The SPF thanks to the “Service Request Mapping” and the “Edge Node coordination”, is able to dynamically to trigger network services at the network level upon request of an application via the User to Service Interface (USI) • The SPF software prototype is currently able to provide • LSP in a (G)MPLS networks • Advanced features (G)MPLS Network • L3 VPN

9. BGP/MPLS VPN Layer 3 service Provisioning • The Layer3 (L3) VPN (RFC4364), offers an approach to create a MPLS-Based Virtual Private Network • L3 VPN offers a routed solution connectivity • L3 VPN is completely based on IPv4 address space • L3 VPN offers a scalable and Multi Domain Layer3 IP-dependentconnectivity • The SPF is responsible for all endpoint of the Domain i.e., it is able to: • Configure and maintain all the Edge Routers • Provide advanced services • Operate on point-to-point Security (IPsec) • SPF-based VPN has the following advantages: • Customer to be UNAWARE of MPLS (all the work is done by the Service Provider) • Customer to be UNAWARE of security policy and technology • Customer to be UNAWARE of connectivity and routing VPN management

10. CE PE PE CE The Testbed AE = Application Entity CSE = Centralised Service Entity DSE = Distribuited Service Element USI = User to Service Interface CE = Customer Edge PE = Provider Edge EU-X = End User X Distributed Java Modules SPF Internal Signaling CSE DSE EU-C UNI Access Network DSE AE DSE USI UNI DSE PE EU-A EU-B WDM UNI Access Network Access Network CE GMPLS Backbone Metro/Core Juniper/Cisco Router Lucent M3000

11. Conclusions Achieved results: • The support of the BGP/MPLS VPN provisioning to application by the SPF prototype was experimentally demonstrated • Multi-Vendor routers interoperability tests for the provisioning of BGP/MPLS VPNservices were executed Future Work: • Three-month mobility action planned starting mid April 2007 (Sant’Anna -> KTH) for the deployment of the SPF prototype within the ACREO testbed • Target papers: NOMS 2008, journals to be decided

12. Activity 5Survivability in all-optical wavelength switching networks PoliMI - CTTC

13. Shared Path Protection • Why SPP? • more efficient use of the network resources • a lower recovery time than dynamic restoration scheme. • Aim: • investigate effects of outdated control information on SPP • investigate requirements and algorithms to apply SPP without wavelength conversion

14. ADRENALINE Architecture • GMPLS-based Intelligent all-Optical Network

15. POLIMI and CTTC • CTTC is currently implementing SPP over an all-optical network testbed (ADRENALINE) • POLIMI has gained a wide experience on simulative comparison of different SPP approaches • Novel proposals: CAFES, PHOTO POLIMI algorithmic expertise CTTC Testbed experience

16. Current activities • Simulation (modelistic approach) to identify and quantify effect of outdated information in a distributed control plane • Role of primary capacity • Role of backup capacity • Reservation Conflict, Sub-optimal Routing, False Saturation Block • Emulation (testbed approach) • SPP implementation on testbed has been finalized • Evaluation of the outdated information in a real distributed GMPLS control plane

17. Blocking Probability Pb • 3 phases: • 1°: outdated information does not influence performance (negligible delay) • 2°: logaritmic increase of Pb for increasing delay • 3°: Pb reaches a saturation value and is no more influenced by the delay 1 0 0 A r 1 0 0 A r 1 0 A r 1 8 0 1 0 % k c 1 o l B P 0 , 1 0 , 0 1 0 , 0 0 1 - -5 0 0 , 0 0 0 1 0 , 0 0 1 0 0 1 0 , 1 1 1 0 1 0 0 1 delay • r • i • t • a • r • d • o • ( • s • )

18. Activity 6: p-Cycle (BME+UC3M)Multi-domain resilience via p-Cycles and related Control Plane Issues David Larrabeiti, Ricardo Romeral Universidad Carlos III de Madrid – Spain (UC3M) {dlarra, rromeral}@it.uc3m.es János Szigeti, Tibor Cinkler Budapest University of Technology and Economics (BME) {szigeti, cinkler}@tmit.bme.hu

19. Classification of protection schemes • when is planned: pre-planned or at failure occurance • resource sharing: dedicated or shared • scope of protection: end-to-end, segment or span • assignment: connection-based, resource-based

20. Multi-domain networks • Reduced topology information about domains • Scalability • Confidentiality • Long links • increased failure probability • 1:1 end-to-end protection does not perform well: • link-disjoint paths cannot be always found • local protection also needed • Responsibilities for failures? • Are failures independent?

21. p-Cycle protection • General p-cycle concepts: • local (span) protection • on-cycle links • straddling links • resource sharing: all on-cycles needed for backup path straddling links not needed to be operational

22. Protecting inter-domain links Entire network – nobody sees it Each operator has two network views: Higher level – inter domain llinks and aggregation between border nodes Lower level – domain operators see their own domain

23. Protecting Inter-domain links On-Cycle link failure Straddling link failure

24. Resolution of HLPC’s (higher level p-cycle) intra domain connection logical connections to realize Most Reliable Least Cost Ring-based

25. Protocollar Issues of HLPC planning • BGP4 does not support it • PCE concept (IETF Path Computation Element WG) • etc.?

26. A signalling Example for PCE: Basic Network Configuration D1 D4 D2 D5 D3 PCE 1 PCE 4 Stradling P-cycle PCE 2 PCE 5 PCE 3

27. D1 D4 D2 D5 D3 On-cycle link Failure Extract from p-cycle Insert to p-cycle LSP 1 X PCE 1 NOTIFY message PCE 4 Stradling P-cycle PCE 2 PCE 5 PCE 3

28. D1 D4 D2 D5 D3 Stradling link Failure Insert into LSP 2 PCE 4 PCE 1 Send via intra-domain tunnel to the p-cycle Extract form p-cycle and send via intra-domain tunnel X Stradling LSP 2 P-cycle Insert into the p-cycle PCE 2 NOTIFY message PCE 5 PCE 3

29. Provided Availabilty tnet E1net

30. Tail behaviour 1st letter C, M, L, X: C: Ring-based M: Most Reliable L: Least Cost X: No Cycles 2nd letter C, M, N, D: C: Inter&Intra p-cycles M: Inter p-cycle & intra dedicated N: no protection D: e2e dedicated prot.

31. Relative thrift • Rate of unavailability reduction and supplementary resource usage: • Highly depends on network topology • At low link failure coefficient the curves are above 1.0 - 0.9

32. Activity 7: MLMC (BME+UC3M)Multicast in Multilayer Optical Networks with Grooming David Larrabeiti, Ricardo Romeral Universidad Carlos III de Madrid – Spain (UC3M) {dlarra, rromeral}@it.uc3m.es Marcell Perényi, Péter Soproni,Tibor Cinkler Budapest University of Technology and Economics (BME) {perenyim, soproni, cinkler}@tmit.bme.hu

33. Problem Formulation Network model: • Two-layer optical WDM network • Electronic layer • Wavelength conversion • Grooming • Optical layer • Space switching • Peer interconnection • Wavelength-graph model

34. Problem Formulation Traffic demands: • Static demands • Unicast • Multicast • or both at the same time • Dynamic demands (in latest simulator)

35. Next joint targets Address bandwidth waste due to grooming Analyse dynamics of the system after a succession of tree requests What happens in high load conditions? Converge to broadcast trees ? Problem: limit of splits How to prevent this? Enhance TE signalling to stem new branches due to grooming Multicast Signalling & further research RSVP-TE for trees

36. Problem Formulation Routing: • Static routing • ILP • Several ILP formulations: • For unicast, multicast, or both at the same time • Dynamic routing (in latest simulator) • ILP based • Dijsktra based • Arbitrary heuristics based (not yet implemented)

37. Physical Device Models • Represented by a sub-graph (easily extensible) • OXC, OEXC, etc. • Multicast capability, two cases are investigated: • Electronic layer branching • Optical layer branching

38. Physical Device Models Example: Electronic layer only branching Both electronic and optical layer branching

39. Technical Constraints • Limitation of branching • e.g. 2-way/3-way branching only • Limitation of: • Electronic layer • Optical layer • Limitation of tree size • Depth limit (limits delay from tree source) • Breadth limit (limit number of leaf nodes) • Limit whole tree size

40. Technical Constraints Soft constraints: • If a constraint is violated, that configuration is not rejected, but penalized • Formally: move from the constraints to the objective function • Even if the whole problem is infeasible, a sub-problem can be feasible

41. Results Number of destinations within a tree Number of trees Multicast scales well with the increasing number of trees and the number of targets in the trees

42. Results Cost gain ratio of optical branching versus electronic layer only branching as a function of optical-electronic cost ratio. Region of cheap optical branching

43. The Simulator

44. The Simulator

45. Activity 8A Comparative Study of Single-layer and Multi-layer Traffic Engineering with Dynamic Logical Topology Construction IBBT (UGent) - Bilkent

46. Single vs. Multi-Layer TE UGent’s Multi-Layer TE Strategy: Lightpath Topology and IP/MPLS routes are calculated according to traffic expectation and updated periodically. Bilkent’s Single-Layer TE Strategy: Static lightpath topology designed making use of traffic expectation. Dynamic IP/MPLS routes, LSPs are rerouted. Blocking Ratios vs Traffic Unpredictibality • A case study is constructed and two strategies are compared on a common platform • + MTE has significantly better bandwidth blocking performance • - Significant number of lightpath changes, i.e. set up and tear down (7.9 lightpaths per hour on a 10 node network) Number of lightpath changes vs. Hours in MTE strategy for a 10 node network

47. What is Ahead? • Next Step: A hybrid strategy combining the advantages of both strategies • Topology will be updated periodically • IP/MPLS routes will be chosen dynamically • The hybrid strategy aims to • Improve the blocking performance • Cause smaller number of set up and tear down of lightpaths These two strategies consider the IP/MPLS and WDM layer, and do not deal with the physical layer. BUTE developed an MTE scheme involving Physical and WDM layers. Final objective is to construct a TE study considering all three layers. Targeted call for papers: ICTON 2007

48. Activity 9Prediction based routing for Multilayer Traffic engineering IBBT (UGent) - UPC

49. Prediction Based Routing for Multilayer TE • UPC’s Prediction Based Routing is a RWA scheme that relies on node-local information only. • The robust nature of PBR (e.g. no reliance on flooding) has proven to perform well in routing Multilayer TE generated lightpath requests (for the IP/MPLS logical topology). • During the joint task, the PBR algorithm and MLTE strategy were integrated on an overlay scenario. • The (optical layer load) information locally collected by the PBR was aggregated into a per node-pair metric that is used to steer the MLTE logical topology generation. Routing Logical topology IP/MPLS MLTE request metric PBR Lightpath routing & wavelength assignment OTN

50. Prediction Based Routing for Multilayer TE • The PBR based load metric allows to optimize only in parts of the network with high load: • No need to optimize highly in lightly loaded parts of the network (this hurts IP/MPLS router loads) • The set of highly loaded IP/MPLS vs. specific traffic pattern is more consistent (IP/MPLS router capacities can be more easily dimensioned). • MLTE strategies can optimize more towards optical layer resource usage be using more point-to-point grooming instead of end-to-end grooming • Of course this increases transit traffic in IP/MPLS nodes • The MLTE logical topology generation normally uses a static optical metric to optimize towards optical resource usage. Better optimization