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Network architecture tools to support network operator requirements Luc Le Beller FTR&D/DAC Present document contains informations proprietary to France Telecom. Accepting this document means for its recipient he or she recognizes the confidential nature of its content and his or her engagement not to reproduce it, not to transmit it to a third party, not to reveal its content and not to use it for commercial purposes without previous FTR&D written consent. Optical World D1 - 25/04/01 Outline Introduction and scope Generic transport layer structure Two examples of IP over optical network configurations Additional architectural components Service description Conclusion France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D2 - 25/04/01 Technical background Transport network architecture is driven by the following items : An important diversity of transport network techniques in the core and the access : SDH, ATM, IP, MPLS, OTN, GbE The development of control(s) plane(s) in addition to management(s) plane(s) : from B-ISDN to ASON A lot of different architectural models coming from the standardisation : ITU-T, IETF, OIF France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D3 - 25/04/01 Operator background Transport network architecture is driven by the following items : Dynamicity Transport costs decreased Monopoly era with reliable voice and LL services demand forecasts is over Emergence of multiple new services with uncertain needs Impact of competitors market share and network architecture options Diversification from raw transport service Provisioning/reconfiguration time enables differentiation from competition Transport carriers must differentiate their services and climb on the value chain Bandwidth on demand (wavelengths, SDH VCs) : OSP (optical service provider) i.e. Storm Modulation of quality of service (protection levels) VPN France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D4 - 25/04/01 Scope Full description of the transport network components G.805 and derived standards, G.8080 and derived standards : very low granularity Consistent top-down (from the service to the network) and bottom-up (from the network to the service) description SG 15 bottom-up approach ; SG 13 top-down approach General interaction between transport network components Depending on organisation structure (actors, business units) Interaction between transport network components and other networks and services components Also depending on organisation structure with more actors and business units France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D5 - 25/04/01 Outline Introduction and scope Generic transport layer structure Two examples of IP over optical network configurations Additional architectural components Service description Conclusion France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D6 - 25/04/01 Generic Layer Structure A generic layer structure for transport network, independent of the techniques, is obtained by combination of the following criteria : - Does the layer provide flexible connectivity (G.805 sub-network capability) or not ? - What type of resources in the layer needs to be reserved in response to a client request for the transport of his (characteristic) information ? Layer(s) offering flexible connectivity and not requiring specific resources allocation for every sub-network is named FW Layer(s) offering flexible connectivity and requiring specific resources allocation for Every sub-network is named SW/XC Layer(s) offering point-to-point connectivity is named PHY layer France Telecom R&D FW SW/XC PHY Diffusion of this document is subject to France Telecom authorization Optical World D7 - 25/04/01 Transport Network Techniques FW IP SW/XC PHY MPLS, ATM VP/VC, SDH VC-X, ETH MAC, OTN ODUk/OCh SDH RS/MS, OTN OTS/OMS ETH PHY, Optical Fiber Not only physical !! It is assumed that a G.805 client/server relationship is existing between all these layers France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D8 - 25/04/01 One example IP IP FW a b ATM VP/VC SW/XC d a a ATM VP c e e VC-4-4c e SDH VC-4/VC-4-4c e k VC-4-4c e c PHY STM-N/WDM k k STM-4 c k k STM-4 Equivalent G.805 representation of a, e, k and c client/server relationships France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D9 - 25/04/01 Outline Introduction and scope Generic transport layer structure Two examples of IP over optical network configurations Additional architectural components Service description Conclusion France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D10 - 25/04/01 IP over optical configurations Optical Network O3 IP Network IP Network O2 R6 I6 I4 R4 O1 I5 IP Network R5 Can both IP adjacencies R4-R6 and R4-R5 coexist on the same I4 interface ? France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D11 - 25/04/01 Concatenated versus channelised CONCATENATED : only one adjacency per interface FW IP CHANNELISED : more than one adjacency per interface IP FW PHY PHY IP STM-16/OF SW/XC SW/XC IP OTN OTN OTN OTN OF PHY OF The SW/CX layer is supporting the PHY layer ! France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D12 - 25/04/01 Outline Introduction and scope Generic transport layer structure Two examples of IP over optical network configurations Additional architectural components Service description Conclusion France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D13 - 25/04/01 General processes For the description of the services telecommunication, it is useful to structure all the actions required to offer a service in the following (and chronologically) way : - pre-sales (PSA) -subscription (SCR) - invocation (INV) - assurance (ASU) - billing (BIL) This structure can also be applied to the transport network and as example to the IP over optical configurations where the service is : creation of an IP adjacency between routeur R4 and R5 IP Network R6 I6 O3 O2 IP Network I4 R4 O1 IP Network R5 I5 France Telecom R&D Optical Network Diffusion of this document is subject to France Telecom authorization Optical World D14 - 25/04/01 Operations for conc. and chan. (1) Operations 1 to 4 are required to create an adjacency between routers R4 and R5 CHANNELISED CONCATENATED PSA 1 2 -Routers localisation SCR 3 -Interfaces I4 and I5 installation 4 -Create optical channel -Routers deployment Step 4 requires a step 3 : the same dynamics applies France Telecom R&D PSA INV 1 -Routers localisation 2 -Routers deployment SCR 3 -Interfaces I4 and I5 installation INV 4 -Create optical channel(s) Step 4 can be independent of step 3 : different dynamics can apply Diffusion of this document is subject to France Telecom authorization Optical World D15 - 25/04/01 Operations for conc. and chan. (2) Optimized procedure for the CONCATENATED configuration PSA 1 -Routers localisation 2 -Routers deployment 3 -Interfaces Ix installation SCR Optimized procedure for the CHANNELISED configuration INV 4 -Create opticals channels This requires the provisioning of routers with the maximum capacity of interfaces PSA SCR 1 -Routers localisation 2 -Routers deployment 3 -Interfaces I4 and I5 installation at maximum bit-rate INV 4 -Create opticals channels This requires installation of interfaces at the highest capacity ! : optimisation is considered from the IP network side France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D16 - 25/04/01 Transport service definition at G.805 level 1) Trail service LIK Y1 Layer Y TRAIL X Layer X A and B : access groups or sub-networks B 2) Sub-network connection service A SNC X Layer X Note : trail service requires at least one sub-network connection service (except if X is a PHY layer) Telecommunication service modelling requires other considerations : additional transport layers, division in actors (partitioning), control plane components, … France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D17 - 25/04/01 Conclusion It has been shown on a basic IP over optical configuration that a technical choice has great impact on the global architecture. This was made possible by a network modelisation at a low-level of granularity, which assembles well defined elementary architectural components. Elementary architectural components must continue to be standardised independently of the technology There is no need to standardize more global architectural tools France Telecom R&D Diffusion of this document is subject to France Telecom authorization Optical World D18 - 25/04/01