12/15/200049th IETF Carriers Service Framework and Associated UNI Requirements Yong Xue [email protected]...
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Transcript of 12/15/200049th IETF Carriers Service Framework and Associated UNI Requirements Yong Xue [email protected]...
12/15/2000 49th IETF
Carriers Service Framework and Associated UNI Requirements
Yong Xue
[email protected]/WorldCom
12/15/2000 49th IETF
Document and Authors
Internet-Draft: <draft-many-carrier-framework-uni-00.txt>
Yong Xue , Daniel Awduche UUNET/WorldComMonica Lazer, John Strand, Jennifer Yates AT&TLarry McAdams CiscoOlga Aparicio, Roderick Dottin Cable & WirelessRahul Aggarwal Redback Networks
12/15/2000 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
12/15/2000 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
12/15/2000 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.
12/15/2000 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
12/15/2000 49th IETF
Optical Network
ONE
ONEONE
ONE
ED
ED
ED
ONE-SR
Sub-rateConnections
Sub-rateConnections
ED : Client Edge DeviceONE : Optical Network Element
Optical Service Path
Optical Lightpath
Optical Lightpath: : ONE-to-ONEOptical Service Path : ED-to-ED
12/15/2000 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.
12/15/2000 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
12/15/2000 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
12/15/2000 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
12/15/2000 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
12/15/2000 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
12/15/2000 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.
12/15/2000 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
12/15/2000 49th IETF
Sub-Rate Service Framework
<= 2.5 Gb/s >= 2.5 Gb/s
<= 2.5 Gb/s >= 10 Gb/s
O NE-SR
ED(ST S-m N ,
ST M -N ,VC -K ,VT -X )
O NE
Granularity >=2.5 Gb/s
Granularity<=2.5 Gb/s
O ptica l Service Path
O ptica l L ightpath
UNIUNI-SR
12/15/2000 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
12/15/2000 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
12/15/2000 49th IETF
Inter-Carrier Network Model
Carrier AOptical Network
Carrier COptical Network
Carrier BOptical Network
ED ED
ED ED
ED
ED
EDED
PUB-UNI
PUB-UNI
PUB-UNIPUB-UNI
PUB-UNI
PUB-UNI
PUB-UNI
PUB-NNI
PUB-NNIPUB-NNI
ED :Client's Edge DevicePUB-UNI/NNI :Public UNI/NNIPRI-UNI/NNI :Private UNI/NNI
12/15/2000 49th IETF
Intra-Carrier Network Model
ED
OpticalSub-Network
OpticalSub-Network
OpticalSub-Network
ED
CED CED
CED
ED
ED
ED
ED
Vendor AOptical network
DSI
DSI
DSI
DSI
PRI-NNI
PRI-NNIPRI-NNI
PRI-UNI
PRI-UNIPRI-UNI
PUB-UNI
PUB-UNI
PUB-UNIPUB-UNI
PUB-UNI
PUB-NNI 3rd PartyNetwork
ED :Client Edge DeviceCED :Carrier Edge DevicePUB-UNI/NNI :Public UNI/NNIPRI-UNI/NNI :Private UNI/NNIDSI :Data Service Interface (ATM, SONET, etc.)
PUB-UNI
PUB-NNI
12/15/2000 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
12/15/2000 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.
12/15/2000 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
12/15/2000 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
12/15/2000 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
12/15/2000 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
12/15/2000 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
12/15/2000 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