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Carriers Service Framework and Associated UNI Requirements Yong Xue yxue@uu.net UUNET/WorldCom. Document and Authors. Internet-Draft: <draft-many-carrier-framework-uni-00.txt> Yong Xue , Daniel Awduche UUNET/WorldCom Monica Lazer, John Strand, Jennifer Yates AT&T
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Carriers Service Framework and Associated UNI Requirements Yong Xue yxue@uu.net UUNET/WorldCom 49th IETF
Document and Authors Internet-Draft: <draft-many-carrier-framework-uni-00.txt> Yong Xue , Daniel Awduche UUNET/WorldCom Monica Lazer, John Strand, Jennifer Yates AT&T Larry McAdams Cisco Olga Aparicio, Roderick Dottin Cable & Wireless Rahul Aggarwal Redback Networks 49th IETF
About This Document • Contains the carrier optical service framework and major requirements developed by OIF Carrier Study Group • These requirements have been used to guide OIF UNI1.0 development and liaisoned to T1X1.5 and ITU SG 13 as input to ITU G.Ason development. • Still a work-in-progress document. Addressing issues of most concern in carriers community and not meant to be complete and comprehensive at this stage. • Cover more than just IP client 49th IETF
Carriers Major Concerns • Viable optical business and service models • UNI and optical connection requirements • Network reference models and support • Security is a big concern: resource and access control • Control plane functions w.r.t UNI • Scalability 49th IETF
Carriers Objectives • Promote a standardized optical control plane with its associated interfaces and protocols to achieve multi-vendor/multi-carrier interoperability. • Provide rapid automatic end-to-end provisioning of optical connection across one or more optical networks. • Support different service and business models including “branded” services, bandwidth-on-demand services , and Optical VPN (OVPN). • Support multiple different client signal types, including IP, ATM, PDH PL, SONET/SDH, and transparent signals • Promote policy-based call acceptance, peering policies and access/resource control. 49th IETF
Carriers Objectives • Support the scalability both at node and network level: several thousands of ports per node and hundreds of switch nodes per network. • Provide restoration, diverse routing and other Qos features within the control plane on a per-service-path basis. • Reduce the need and cost for carrier developed OSS software development 49th IETF
Optical Network 49th IETF
Optical Network • Major Components • Optical Network Elements (ONE): OXC, OADM • User Edge Device (UED): IP Router, ATM, FR, SONET • Sub-networks • DWDM Optical Line System (OLS) • Network Access Methods • Cross-office (co-located) • Inter-office (remote) • Via third-party carrier • Abstract Model: A set of ingress/egress ports and a well-defined set of p2p optical connection services. 49th IETF
Basic Optical Service Models • Provisioned Bandwidth Service (PBS) • “Point and click” and static near-real-time provisioning through management interface (via NMS or OSS) • Client/Server relationship between clients and optical network • Customer has no network visibility and depends on network intelligence. • Bandwidth on Demand Service (BODS) • Signaled connection request via UNI • Dynamic and real-time provisioning in seconds or sub-seconds • Customer has no, limited or full network visibility depending upon interconnecting and control model used • Rely on network or client intelligence based on the interconnecting and control model used 49th IETF
Basic Optical Service Models • Optical Virtual Private Network (OVPN) • Customers contract for specific set network resources such as link bandwidth, wavelength, and/or optical connection ports. • Closed User Group (CUS) and virtual network • Optical connection can be based on signaled or static provisioning • Customer may have limited visibility and control of contracted network resources 49th IETF
Optical Connection Services • Service Definition: • A fixed bandwidth connection between an ingress port and an egress port across the optical transport network. • Optical Connection Behavior Defined by its Attributes: • identification-based: unique connection ID, contract ID, user group ID, source and destination identifiers (address, port, channel and sub-channel) • characteristics-based: framing ( type, bandwidth, transparency, directionality), priority, protection (1+1, 1:n, unprotected, etc.), scheduling and service level. • Routing-based: diversity 49th IETF
Optical Connection Services • Optical Connection Operations • Requests to create, delete, modify and query an optical connection • Only non-destructive attribute modification is allowed. • A status code should be returned for each operation request. • Same functions should be available via management interface 49th IETF
Service Requirements • Service Type and Granularity • SONET/SDH: STS-n/STM-m • OC-48/STM-16 & OC-192/STM-64 • OC-768/STM-256 • Ethernet: 1Gb/s E, 10Gb/s E (LAN and WAN mode) • PDH: DS1/E1, DS3/E3, … • Other Choices • Sub-rates multiplexed interfaces (both channelized and concatenated) • G.709 digital wrapper, • selectable rates interfaces, • composite interfaces • Interface Type vs. Service Type 49th IETF
Service Requirements • Addressing Schema • Separation of client network and optical network address space • Provisioning based on the client address or names, including IP, NSAP and E.164 • Address resolution and address translation service should be provided by the optical network. • Qos Service Mapping from SLA Contract • Service provider has flexibility to map different class of services (COS) to its own set of priority, protection, restoration parameters. 49th IETF
Sub-Rate Service Framework • Wavelength (Lambda) switching at DWMD channel rate ( OC-48/STM-16 and up) in optical domain. • Sub-Rate: • switched at less than 2.5Gb/s switching in the electrical domain • Sub-rate extension to UNI: UNI-SR • Separate process for ONE-SR • ONE-SR • Multiplexing/demultiplexing • Mapping and adaptation • Possible implementation: separate box or software process 49th IETF
Sub-Rate Service Framework 49th IETF
Network Reference Model • An Optical Network Can be Decomposed into Three Logical Network Planes • User Data Plane (U-Plane) • Control Plane (C-Plane) • Management Plane (M-Plane) • Each Logical Network Plane Consists of • A plane-specific set of networking functions • A transport network • Optical Networking Function • optical connection routing • optical connection switching • optical connection multiplexing/demultiplexing • optical connection protection and restoration 49th IETF
Carrier Network Reference Model • Consists of one or more sub-networks • With equipment from single or multiple vendors • With equipment based on single or multiple technologies • Interfaces Reference Points • User-Network Interface (UNI) and Network-Network Interface (NNI) • Private vs. Public UNI/NNI: Based on trust relationship between interconnected optical domains • Data Service Interface (DSI) • UNI Sub-rate (UNI-SR) • Inter-carrier vs. Intra-carrier model 49th IETF
Inter-Carrier Network Model 49th IETF
Intra-Carrier Network Model 49th IETF
Control Plane Architecture • Control Plane Functions • Signaling and Routing • Resource, end-systems and service discovery • End-to-end auto optical connection provisioning, tear-down, and management • Support direct switching cross-connect provisioning for permanent connection • Support various optical connection protection and restoration schema • Control Plane Function Access Support via: • UNI • NNI • NMS/EMS 49th IETF
UNI Signaling Model • UNI-C and UNI-N Control Process • Functional entities for signaling associated with client-side ED and network-side ONE. • Tightly-coupled vs. loosely-coupled. • Signaling Methods • IN-Band:Signaling messages carried over a logical communication channel embedded in the data-carrying optical link or channel between UNI-C and UNI-N • Out-of-Band: Signaling messages carried over a dedicated communication channel or fiber path separate from the data-carrying optical link or channel between UNI-C and UNI-N • In-Fiber vs. Out-of-Fiber • Third-party Signaling: UNI-C is non-ED resident and directly communicates with UNI-N of ONE on behalf of ED. 49th IETF
Service and End-System Discovery • Service Discovery • Querying and Signaling to ED available services and parameters • Support automatic service request and provisioning • Carried by the service discovery protocol • End-System Discovery • Auto identification between ONE and ED, and between ONEs • Link connection state discovery • Auto address registration/de-registration • Carried by the service discovery protocol • Exchange of defined set of local topological and identity information • Exchanged information accessible via management interface 49th IETF
Routing Functions and Models • Routing Function: • Dissemination and propagation of reachability, resource, and topological information. • Optical connection path computation. • Route Generation • Static configuration • Route server • Dynamic learning via routing protocol • Routing Model • Overlay, Peer and Augmented • Carriers are very sensitive to routing model selection due to security and scalability concerns. • Configurable and enforceable routing control policy should be supported at UNI/NNI 49th IETF
Routing Functions and Models • Overlay Model • Optical network and client networks are independent routing domains • No routing information exchanged at UNI/NNI • Required support at both private UNI/NNI and Public UNI/NNI • Peer Model • Optical network and client networks are integrated routing domains and running the same routing protocol • Full or partial routing information exchanged at UNI/NNI • Support only allowed at private UNI/NNI • Some possible scaling issues 49th IETF
Routing Functions and Models • Augmented Model • Optical network and client networks are independent routing domains • Only client network reachabilty information carried across optical network and advertised to other clients. • An inter-domain routing protocol used at UNI/NNI • May be supported at both private UNI/NNI and public UNI/NNI 49th IETF
Routing Constraint Support • Diversity • Shared Risk Link Group (SRLG) • K-out-of N Diversity • Hierarchical and Geographic Diversity (Node/Network/Location) • Channel Grouping • TDM Multiplexed Sub-channels Bundling • Wavelength Grouping (Waveband) • Edge Compatibility • Laser Frequency • Compatible Adaptation Functions • User/Peer Group 49th IETF
Security and Access Control • Trust Relationship Between Network and Clients as Well as Between Two Networks • Trusted vs. untrusted relation • Distinguish between private and public UNI/NNI interfaces at network demarcation points. • Policy-Based Control • Configurable and enforceable policy-based access/resource control at UNI/NNI Interfaces • Different policy defined at private and public interfaces • Service Request Authentication and Authorization • Network Resources Information Access Control • Firewall between UNI and NNI 49th IETF
Questions ? Thanks! 49th IETF