Network Working Group                       Daniele Ceccarelli (Editor)
Internet Draft                                                 Ericsson

Intended status: Informational                       Young Lee (Editor)
Expires: September 2015                                          Huawei

                                                          March 9, 2015

      Framework for Abstraction and Control of Transport Networks


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   carefully, as they describe your rights and restrictions with
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   This draft provides a framework for abstraction and control of
   transport networks.

Table of Contents

   1. Introduction...................................................2
   2. Business Model of ACTN.........................................5
      2.1. Customers.................................................5
      2.2. Service Providers.........................................7
      2.3. Network Providers.........................................8
   3. ACTN architecture..............................................8
      3.1. Customer Network Controller..............................12
      3.2. Multi Domain Service Coordinator.........................13
      3.3. Physical Network Controller..............................14
      3.4. ACTN interfaces..........................................15
      3.5. Work in Scope of ACTN....................................17
   4. References....................................................21
      4.1. Informative References...................................21
   5. Contributors..................................................24
   Authors' Addresses...............................................24

1. Introduction

   Transport networks have a variety of mechanisms to facilitate
   separation of data plane and control plane including distributed
   signaling for path setup and protection, centralized path
   computation for planning and traffic engineering, and a range of
   management and provisioning protocols to configure and activate
   network resources. These mechanisms represent key technologies for
   enabling flexible and dynamic networking.

   Transport networks in this draft refer to a set of different type of
   connection-oriented networks, primarily Connection-Oriented Circuit
   Switched (CO-CS) networks and Connection-Oriented Packet Switched
   (CO-PS) networks. This implies that at least the following transport
   networks are in scope of the discussion of this draft: Layer 1(L1)

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   and Layer 0 (L0) optical networks (e.g., Optical Transport Network
   (OTN), Optical Channel Data Unit (ODU), Optical Channel
   (OCh)/Wavelength Switched Optical Network (WSON)), Multi-Protocol
   Label Switching - Transport Profile (MPLS-TP), Multi-Protocol Label
   Switching - Traffic Engineering (MPLS-TE), as well as other emerging
   technologies with connection-oriented behavior. One of the
   characteristics of these network types is the ability of dynamic
   provisioning and traffic engineering such that resource guarantees
   can be provided to their clients.

   One of the main drivers for Software Defined Networking (SDN) is a
   decoupling of the network control plane from the data plane. This
   separation of the control plane from the data plane has been already
   achieved with the development of MPLS/GMPLS [GMPLS] and PCE [PCE]
   for TE-based transport networks. One of the advantages of SDN is its
   logically centralized control regime that allows a global view of
   the underlying network under its control. Centralized control in SDN
   helps improve network resources utilization from a distributed
   network control. For TE-based transport network control, PCE is
   essentially equivalent to a logically centralized control for path
   computation function.

   Two key aspects that need to be solved by SDN are:

     . Network and service abstraction
     . End to end coordination of multiple SDN and pre-SDN domains
        e.g. NMS, MPLS-TE or GMPLS.

   As transport networks evolve, the need to provide network and
   service abstraction has emerged as a key requirement for operators;
   this implies in effect the virtualization of network resources so
   that the network is "sliced" for different tenants shown as a
   dedicated portion of the network resources

   Particular attention needs to be paid to the multi-domain case,
   where Abstraction and Control of Transport Networks (ACTN) can
   facilitate virtual network operation via the creation of a single
   virtualized network or a seamless service. This supports operators
   in viewing and controlling different domains (at any dimension:
   applied technology, administrative zones, or vendor-specific
   technology islands) as a single virtualized network.

   Network virtualization, in general, refers to allowing the customers
   to utilize a certain amount of network resources as if they own them
   and thus control their allocated resources in a way most optimal
   with higher layer or application processes. This empowerment of
   customer control facilitates introduction of new services and

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   applications as the customers are permitted to create, modify, and
   delete their virtual network services. More flexible, dynamic
   customer control capabilities are added to the traditional VPN along
   with a customer specific virtual network view. Customers control a
   view of virtual network resources, specifically allocated to each
   one of them. This view is called an abstracted network topology.
   Such a view may be specific to the set of consumed services as well
   as to a particular customer. As the Customer Network Controller is
   envisioned to support a plethora of distinct applications, there
   would be another level of virtualization from the customer to
   individual applications.

   The framework described in this draft is named Abstraction and
   Control of Transport Network (ACTN) and facilitates:

     - Abstraction of the underlying network resources to higher-layer
        applications and users (customers); abstraction for a specific
        application or customer is referred to as virtualization in the
        ONF SDN architecture. [ONF-ARCH]

     - Slicing infrastructure to connect multiple customers to meet
        specific customer's service requirements;

     - Creation of a virtualized environment allowing operators to
        view and control multi-subnet multi-technology networks into a
        single virtualized network;

     - Possibility of providing a customer with abstracted network or
        abstracted services (totally hiding the network).

     - A virtualization/mapping network function that adapts customer
        requests to the virtual resources (allocated to them) to the
        supporting physical network control and performs the necessary
        mapping, translation, isolation and security/policy
        enforcement, etc.; This function is often referred to as

     - The multi-domain coordination of the underlying transport
        domains, presenting it as an abstracted topology to the
        customers via open and programmable interfaces. This allows for
        the recursion of controllers in a customer-provider

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   The organization of this draft is as follows. Section 2 provides a
   discussion for a Business Model, Section 3 ACTN Architecture,
   Section 4 ACTN Applicability, and Section 5 ACTN Interface

2. Business Model of ACTN

   The traditional Virtual Private Network (VPN) and Overlay Network
   (ON) models are built on the premise that one single network
   provider provides all virtual private or overlay networks to its
   customers. This model is simple to operate but has some
   disadvantages in accommodating the increasing need for flexible and
   dynamic network virtualization capabilities.

   The ACTN model is built upon entities that reflect the current
   landscape of network virtualization environments. There are three
   key entities in the ACTN model [ACTN-PS]:

     - Customers
     - Service Providers
     - Network Providers

    2.1. Customers

   Within the ACTN framework, different types of customers may be taken
   into account depending on the type of their resource needs, on their
   number and type of access. As example, it is possible to group them
   into two main categories:

   Basic Customer: Basic customers include fixed residential users,
   mobile users and small enterprises. Usually the number of basic
   customers is high; they require small amounts of resources and are
   characterized by steady requests (relatively time invariant). A
   typical request for a basic customer is for a bundle of voice
   services and internet access. Moreover basic customers do not modify
   their services themselves; if a service change is needed, it is
   performed by the provider as proxy and they generally have very few
   dedicated resources (subscriber drop), with everything else shared
   on the basis of some SLA, which is usually best-efforts.

   Advanced Customer: Advanced customers typically include enterprises,
   governments and utilities. Such customers can ask for both point to
   point and multipoint connectivity with high resource demand
   significantly varying in time and from customer to customer. This is
   one of the reasons why a bundled services offer is not enough but it
   is desirable to provide each of them with customized virtual network

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   services. Advanced customers may own dedicated virtual resources, or
   share resources, but shared resources are likely to be governed by
   more complex SLA agreements; moreover they may have the ability to
   modify their service parameters directly (within the scope of their
   virtualized environments. As customers are geographically spread
   over multiple network provider domains, the necessary control and
   data interfaces to support such customer needs is no longer a single
   interface between the customer and one single network provider. With
   this premise, customers have to interface multiple providers to get
   their end-to-end network connectivity service and the associated
   topology information. Customers may have to support multiple virtual
   network services with different service objectives and QoS
   requirements. For flexible and dynamic applications, customers may
   want to control their allocated virtual network resources in a
   dynamic fashion. To allow that, customers should be given an
   abstracted view of topology on which they can perform the necessary
   control decisions and take the corresponding actions. ACTN's primary
   focus is Advanced Customers.

   Customers of a given service provider can in turn offer a service to
   other customers in a recursive way. An example of recursiveness with
   2 service providers is shown below.

     - Customer (of service B)
     - Customer (of service A) & Service Provider (of service B)
     - Service Provider (of service A)
     - Network Provider

   +------------------------------------------------------------+   ---
   |                                                            |    ^
   |                                     Customer (of service B)|    .
   | +--------------------------------------------------------+ |    B
   | |                                                        | |--- .
   | |Customer (of service A) & Service Provider(of service B)| | ^  .
   | | +---------------------------------------------------+  | | .  .
   | | |                                                   |  | | .  .
   | | |                    Service Provider (of service A)|  | | A  .
   | | |+------------------------------------------+       |  | | .  .
   | | ||                                          |       |  | | .  .
   | | ||                          Network provider|       |  | | v  v
   | | |+------------------------------------------+       |  | |------
   | | +---------------------------------------------------+  | |
   | +--------------------------------------------------------+ |

                     Figure 1: Network Recursiveness.

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    2.2. Service Providers

   Service providers are the providers of virtual network services to
   their customers. Service providers may or may not own physical
   network resources. When a service provider is the same as the
   network provider, this is similar to traditional VPN models. This
   model works well when the customer maintains a single interface with
   a single provider.  When customer location spans across multiple
   independent network provider domains, then it becomes hard to
   facilitate the creation of end-to-end virtual network services with
   this model.

   A more interesting case arises when network providers only provide
   infrastructure while service providers directly interface their
   customers. In this case, service providers themselves are customers
   of the network infrastructure providers. One service provider may
   need to keep multiple independent network providers as its end-users
   span geographically across multiple network provider domains.

   Customer            X -----------------------------------X

   Service Provider A  X -----------------------------------X

   Network Provider B                     X-----------------X

   Network Provider A  X------------------X

   The ACTN network model is predicated upon this three tier model and
   is summarized in figure below:

                       |       customer       |
                                 |   /\  Service/Customer specific
                                 |   ||  Abstract Topology
                                 |   ||
                       +----------------------+  E2E abstract
                       |  Service Provider    | topology creation
                       /         |            \

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                      /          |             \  Network Topology
                     /           |              \ (raw or abstract)
                    /            |               \
   +------------------+   +------------------+   +------------------+
   |Network Provider 1|   |Network Provider 2|   |Network Provider 3|
   +------------------+   +------------------+   +------------------+

                        Figure 2: Three tier model.

   There can be multiple types of service providers.

     . Data Center providers: can be viewed as a service provider type
        as they own and operate data center resources to various WAN
        clients, they can lease physical network resources from network
     . Internet Service Providers (ISP): can be a service provider of
        internet services to their customers while leasing physical
        network resources from network providers.
     . Mobile Virtual Network Operators (MVNO): provide mobile
        services to their end-users without owning the physical network

   The network provider space is the one where recursiveness occurs. A
   customer-provider relationship between multiple service providers
   can be established leading to a hierarchical architecture of
   controllers within service provider network.

    2.3. Network Providers

   Network Providers are the infrastructure providers that own the
   physical network resources and provide network resources to their
   customers. The layered model proposed by this draft separates the
   concerns of network providers and customers, with service providers
   acting as aggregators of customer requests.

3. ACTN architecture

   This section provides a high-level control and interface model of

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   The ACTN architecture, while being aligned with the ONF SDN
   architecture [ONF-ARCH], is presenting a 3-tiers reference model. It
   allows for hierarchy and recursiveness not only of SDN controllers
   but also of traditionally controlled domains. It defines three types
   of controllers depending on the functionalities they implement. The
   main functionalities that are identified are:

     . Multi domain coordination function: With the definition of
        domain being "everything that is under the control of the same
        controller",it is needed to have a control entity that oversees
        the specific aspects of the different domains and to build a
        single abstracted end-to-end network topology in order to
        coordinate end-to-end path computation and path/service

     . Virtualization/Abstraction function: To provide an abstracted
        view of the underlying network resources towards customer,
        being it the client or a higher level controller entity. It
        includes computation of customer resource requests into virtual
        network paths based on the global network-wide abstracted
        topology and the creation of an abstracted view of network
        slices allocated to each customer, according to customer-
        specific virtual network objective functions, and to the
        customer traffic profile.

     . Customer mapping function: In charge of mapping customer VN
        setup commands into network provisioning requests to the
        Physical Network Controller (PNC) according to business OSS/NMS
        provisioned static or dynamic policy. Moreover it provides
        mapping and translation of customer virtual network slices into
        physical network resources

     . Virtual service coordination: Virtual service coordination
        function in ACTN incorporates customer service-related
        knowledge into the virtual network operations in order to
        seamlessly operate virtual networks while meeting customer's
        service requirements.

         The functionality is covering two types of services:

         - Service-aware Connectivity Services: This category includes
           all the network service operations used to provide
           connectivity between customer end-points while meeting
           policies and service related constraints. The data model for
           this category would include topology entities such as

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           virtual nodes, virtual links, adaptation and termination
           points and service-related entities such as policies and
           service related constraints. (See Section 4.2.2)

         - Network Function Virtualization Services: These kinds of
           services are usually setup between customers' premises and
           service provider premises and are provided mostly by cloud
           providers or content delivery providers. The context may
           include, but not limited to a security function like
           firewall, a traffic optimizer, the provisioning of storage
           or computation capacity where the customer does not care
           whether the service is implemented in a given data center or
           another. These services may be hosted virtually by the
           provider or physically part of the network. This allows the
           service provider to hide his own resources (both network and
           data centers) and divert customer requests where most
           suitable. This is also known as "end points mobility" case
           and introduces new concepts of traffic and service
           provisioning and resiliency. (e.g. Virtual Machine
           mobility)." (See Section 4.2.3)

         About the Customer service-related knowledge it includes:

         - VN Service Requirements: The end customer would have
           specific service requirements for the VN including the
           customer endpoints access profile as well as the E2E
           customer service objectives. The ACTN framework
           architectural "entities" would monitor the E2E service
           during the lifetime of VN by focusing on both the
           connectivity provided by the network as well as the customer
           service objectives. These E2E service requirements go beyond
           the VN service requirements and include customer
           infrastructure as well.

         - Application Service Policy: Apart for network connectivity,
           the customer may also require some policies for application
           specific features or services. The ACTN framework would take
           these application service policies and requirements into
           consideration while coordinating the virtual network
           operations, which require end customer connectivity for
           these advanced services.

   While the "types" of controller defined are shown in Figure 3 below
   and are the following:

     . CNC - Customer Network Controller

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     . MDSC - Multi Domain Service Coordinator
     . PNC - Physical Network Controller

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   VPN customer         NW Mobile Customer     ISP NW service Customer
       |                         |                           |
   +-------+                 +-------+                   +-------+
   | CNC-A |                 | CNC-B |                   | CNC-C |
   +-------+                 +-------+                   +-------+
         \___________            |             _____________/
          ----------             |             ------------
                     \           |            /
                      |         MDSC          |
            __________/          |            \_________
            ----------           |             ------------____
           /                     |                         \
   +-------+                 +-------+                   +-------+
   |  PNC  |                 |  PNC  |                   |  PNC  |
   +-------+                 +-------+                   +-------+
        | GMPLS             /      |                      /    \
        | trigger          /       |                     /      \
       --------       __----      +-----+  __        +-----+     \
      (        )       (    )_    | PNC |__          | PCE |      \
      -        -      ( Phys )    +-----+            +-----+    -----
     (  GMPLS   )      (Netw)        |                /        (     )
    (  Physical  )      ----         |               /        ( Phys. )
     (  Network )                 -----        -----           ( Net )
      -        -                 (     )      (     )           -----
      (        )                ( Phys. )    ( Phys  )
       --------                  ( Net )      ( Net )
                                  -----        -----

                     Figure 3: ACTN Control Hierarchy

    3.1. Customer Network Controller

   A Virtual Network Service is instantiated by the Customer Network
   Controller via the CMI (CNC-MDSC Interface). As the Customer Network
   Controller directly interfaces the application stratum, it
   understands multiple application requirements and their service
   needs. It is assumed that the Customer Network Controller and the
   MDSC have a common knowledge on the end-point interfaces based on
   their business negotiation prior to service instantiation. End-point
   interfaces refer to customer-network physical interfaces that
   connect customer premise equipment to network provider equipment.
   Figure 10 in Appendix shows an example physical network topology
   that supports multiple customers. In this example, customer A has

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   three end-points A.1, A.2 and A.3. The interfaces between customers
   and transport networks are assumed to be 40G OTU links.

   In addition to abstract networks, ACTN allows to provide the CNC
   with services. Example of services include connectivity between one
   of the customer's end points with a given set of resources in a data
   center from the service provider.

    3.2. Multi Domain Service Coordinator

   The MDSC (Multi Domain Service Coordinator) sits between the CNC
   (the one issuing connectivity requests) and the PNCs (Physical
   Network Controllersr - the ones managing the physical network
   resources). The MDSC can be collocated with the PNC, especially in
   those cases where the service provider and the network provider are
   the same entity.

   The internal system architecture and building blocks of the MDSC are
   out of the scope of ACTN. Some examples can be found in the
   Application Based Network Operations (ABNO) architecture [ABNO] and
   the ONF SDN architecture [ONF-ARCH].

   The MDSC is the only building block of the architecture that is able
   to implement all the four ACTN main functionalities, i.e. multi
   domain coordination function, virtualization/abstraction function,
   customer mapping function and virtual service coordination.
   A hierarchy of MDSCs can be foreseen for scalability and
   administrative choices.

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   +-------+                 +-------+                 +-------+
   | CNC-A |                 | CNC-B |                 | CNC-C |
   +-------+                 +-------+                 +-------+
         \___________            |             ___________/
          ----------             |             ----------
                     \           |            /
                      |         MDSC          |
            __________/          |            \_________
            ----------           |             -----------____
           /                     |                        \
   +----------+              +----------+             +--------+
   |   MDSC   |              |   MDSC   |             |  MDSC  |
   +----------+              +----------+             +--------+
        |                    /     |                     /    \
        |                   /      |                    /      \
     +-----+           +-----+  +-----+            +-----+  +-----+
     | PNC |           | PNC |  | PNC |            | PNC |  | PNC |
     +-----+           +-----+  +-----+            +-----+  +-----+

                    Figure 4: Controller recursiveness

   A key requirement for allowing recursion of MDSCs is that a single
   interface needs to be defined both for the north and the south
   In order to allow for multi-domain coordination a 1:N relationship
   must be allowed between MDSCs and between MDSCs and PNCs (i.e. 1
   parent MDSC and N child MDSC or 1 MDSC and N PNCs). In addition to
   that it could be possible to have also a M:1 relationship between
   MDSC and PNC to allow for network resource partitioning/sharing
   among different customers not necessarily connected to the same MDSC
   (e.g. different service providers).
   It should be noted that the interface between the parent MDSC and a
   child MDSC does not introduce any complexity as it is "internal" and
   "transparent" from the perspective of the CNCs and the PNCs and it
   makes use of the same interface model and its primitives as the CMI
   and MPI.

    3.3. Physical Network Controller

   The physical network controller is the one in charge of configuring
   the network elements, monitoring the physical topology of the
   network and passing it, either raw or abstracted, to the MDSC.

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   The internal architecture of the PNC, his building blocks and the
   way it controls its domain, are out of the scope of ACTN. Some
   examples can be found in the Application Based Network Operations
   (ABNO) architecture [ABNO] and the ONF SDN architecture [ONF-ARCH]

   The PNC, in addition to being in charge of controlling the physical
   network, is able to implement two of the four ACTN main
   functionalities: multi domain coordination function and
   virtualization/abstraction function
   A hierarchy of PNCs can be foreseen for scalability and
   administrative choices.

    3.4. ACTN interfaces

   To allow virtualization and multi domain coordination, the network
   has to provide open, programmable interfaces, in which customer
   applications can create, replace and modify virtual network
   resources and services in an interactive, flexible and dynamic
   fashion while having no impact on other customers. Direct customer
   control of transport network elements and virtualized services is
   not perceived as a viable proposition for transport network
   providers due to security and policy concerns among other reasons.
   In addition, as discussed in the previous section, the network
   control plane for transport networks has been separated from data
   plane and as such it is not viable for the customer to directly
   interface with transport network elements.

   While the current network control plane is well suited for control
   of physical network resources via dynamic provisioning, path
   computation, etc., a multi service domain controller needs to be
   built on top of physical network controller to support network
   virtualization. On a high-level, virtual network control refers to a
   mediation layer that performs several functions:

   Figure 4 depicts a high-level control and interface architecture for
   ACTN. A number of key ACTN interfaces exist for deployment and
   operation of ACTN-based networks. These are highlighted in Figure 4
   (ACTN Interfaces) below:

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               -------------   |
              | Application |--
                     | I/F A                 --------
                     v                      (        )
                --------------             -          -
               | Customer     |           (  Customer  )
               |  Network     |--------->(    Network   )
               |   Controller |           (            )
                --------------             -          -
                     ^                      (        )
                     | I/F B                 --------
                     v                        ^    ^
                --------------                :    :
               | MultiDomain  |               :     .
               |  Service     |               :      .
               |   Coordinator|            --------   . I/F E
                --------------            (        )   .
                     ^                   -          -   .
                     | I/F C            (  Physical  )   .
                     v                 (    Network   )   .
                  ---------------       (            )     --------
                 |               |<----> -          -     (        )
                --------------   |        (        )     -         -
               | Physical     |--          --------     (  Physical  )
               |  Network     |<---------------------->(    Network   )
               |   Controller |         I/F D           (            )
                --------------                           -         -
                                                          (        )

                         Figure 4: ACTN Interfaces

   The interfaces and functions are described below:

     . Interface A: A north-bound interface (NBI) that will
        communicate the service request or application demand. A
        request will include specific service properties, including:
        services, topology, bandwidth and constraint information.

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     . Interface B: The CNC-MDSC Interface (CMI) is an interface
        between a Customer Network Controller and a Multi Service
        Domain Controller. It requests the creation of the network
        resources, topology or services for the applications. The
        Virtual Network Controller may also report potential network
        topology availability if queried for current capability from
        the Customer Network Controller.

     . Interface C: The MDSC-PNC Interface (MPI) is an interface
        between a Multi Domain Service Coordinator and a Physical
        Network Controller. It communicates the creation request, if
        required, of new connectivity of bandwidth changes in the
        physical network, via the PNC. In multi-domain environments,
        the MDSC needs to establish multiple MPIs, one for each PNC, as
        there are multiple PNCs responsible for its domain control.

     . Interface D: The provisioning interface for creating forwarding
        state in the physical network, requested via the Physical
        Network Controller.

     . Interface E: A mapping of physical resources to overlay

   The interfaces within the ACTN scope are B and C.

3.5. Work in Scope of ACTN

   This section provides a summary of use-cases in terms of two
   categories: (i) service-specific requirements; (ii) network-related

   Service-specific requirements listed below are uniquely applied to
   the work scope of ACTN. Service-specific requirements are related to
   virtual service coordination function defined in Section 3. These
   requirements are related to customer's VNs in terms of service
   policy associated with VNs such as service performance objectives,
   VN endpoint location information for certain required service-
   specific functions (e.g., security and others), VN survivability
   requirement, or dynamic service control policy, etc.

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   Network-related requirements are related to virtual network
   operation function defined in Section 3. These requirements are
   related to multi-domain and multi-layer signaling, routing,
   protection/restoration and synergy, re-optimization/re-grooming,
   etc. These requirements are not inherently unique for the scope of
   ACTN but some of these requirements are in scope of ACTN, especially
   for coherent/seamless operation aspect of multiple controller

   The following table gives an overview of service-specific
   requirements and network-related requirements respectively for each
   ACTN use-case and identifies the work in scope of ACTN.

   Details on these requirements will be developed into the information
   model in [ACTN-Info].

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    Use-case     Service-          Network-related     ACTN Work
                 specific          Requirements        Scope

    -------      --------------    ---------------     --------------
    [Cheng]      - E2E service     - Multi-layer       - Dynamic
                 provisioning      (L2/L2.5)           multi-layer
                 - Performance     coordination        coordination
                 monitoring        - VNO for multi-    based on
                 - Resource        domain transport    utilization is
                 utilization       networks            in scope of
                 abstraction                            ACTN
                                                        - YANG for

    -------      --------------    ----------------    --------------
    [Dhody]      - Service         - POI               - Performance
                 awareness/        Performance         related data
                 coordination      monitoring          model may be
                 between P/O.      - Protection/       in scope of
                                    Restoration         ACTN
                                    synergy             - Customer's
                                                        toration is
                                                        unique to

    -------      --------------    ----------------    --------------
    [Fang]       - Dynamic VM      - On-demand         - Multi-
                 migration         virtual circuit     destination
                 (service),        request             service
                 Global load       - Network Path      selection
                 balancing         Connection          policy
                 (utilization      request             enforcement
                 efficiency),                           and its
                 Disaster                               related
                 recovery                               primitives/inf
                 - Service-                             ormation are
                 aware network                          unique to

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                 query                                  ACTN.
                 - Service                              - Service-
                 Policy                                 aware network
                 Enforcement                            query and its
                                                        data model can
                                                        be extended by

    -------      --------------    ----------------    --------------
    [Klee]                         - Two stage path    - Multi-domain
                                    computation         service policy
                                    E2E signaling       coordination
                                    coordination        to network
                                                        primitives is
                                    - Abstraction of    in scope of
                                    inter-domain        ACTN
                                    - Enforcement of
                                    network policy
                                    (peering, domain
                                    - Network
                                    level, etc.)

    -------      --------------    ----------------    --------------
    [Kumaki]     - On-demand VN                         - All of the
                 creation                               service-
                 - Multi-                               specific lists
                 service level                          in the left
                 for VN                                 column is
                 - VN                                   unique to
                 survivability                          ACTN.

    -------      --------------    ----------------    --------------
    [Lopez]      - E2E             - E2E connection    - Escalation
                 accounting and    management, path    of performance
                 resource usage    provisioning        and fault
                 data              - E2E network       management

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                 - E2E service     monitoring and      data to CNC
                 policy            fault management    and the policy
                 enforcement                            enforcement
                                                        for this area
                                                        is unique to

    -------      --------------    ----------------    --------------
    [Shin]       - Current         - LB for            - Multi-layer
                 network           recovery            routing and
                 resource          - Multi-layer       optimization
                 abstraction       routing and         are related to
                 Endpoint/DC       optimization        VN's dynamic
                 dynamic           coordination        endpoint
                 selection (for                         selection
                 VM migration)                          policy.

    -------      --------------    ----------------    --------------
    [Xu]         - Dynamic         - Traffic           - Dynamic
                 service           monitoring          service
                 control policy    - SLA monitoring    control policy
                 enforcement                            enforcement
                 - Dynamic                              and its
                 service                                control
                 control                                primitives are
                                                        in scope of
                                                        - Data model
                                                        to support
                                                        data is an
                                                        extension of
                                                        YANG model
                                                        ACTN can

4. References

    4.1. Informative References

   [PCE]     Farrel, A., Vasseur, J.-P., and J. Ash, "A Path
             Computation Element (PCE)-Based Architecture", IETF RFC
             4655, August 2006.

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   [PCE-S]   Crabbe, E, et. al., "PCEP extension for stateful
             PCE",draft-ietf-pce-stateful-pce, work in progress.

   [GMPLS]   Manning, E., et al., "Generalized Multi-Protocol Label
             Switching (GMPLS) Architecture", RFC 3945, October 2004.

   [NFV-AF]  "Network Functions Virtualization (NFV); Architectural
             Framework", ETSI GS NFV 002 v1.1.1, October 2013.

   [ACTN-PS] Y. Lee, D. King, M. Boucadair, R. Jing, L. Contreras
             Murillo, "Problem Statement for Abstraction and Control of
             Transport Networks", draft-leeking-actn-problem-statement,
             work in progress.

   [ONF]     Open Networking Foundation, "OpenFlow Switch Specification
             Version 1.4.0 (Wire Protocol 0x05)", October 2013.

   [ABNO]    King, D., and Farrel, A., "A PCE-based Architecture for
             Application-based Network Operations", draft-farrkingel-
             pce-abno-architecture, work in progress.

   [ACTN-Info] Y. Lee, S. Belotti, D. Dhody, "Information Model for
             Abstraction and Control of Transport Networks", draft-
             leebelotti-teas-actn-info, work in progress.

   [Cheng] W. Cheng, et. al., "ACTN Use-cases for Packet Transport
             Networks in Mobile Backhaul Networks", draft-cheng-actn-
             ptn-requirements, work in progress.

   [Dhody] D. Dhody, et. al., "Packet Optical Integration (POI) Use
             Cases for Abstraction and Control of Transport Networks
             (ACTN)", draft-dhody-actn-poi-use-case, work in progress.

   [Fang] L. Fang, "ACTN Use Case for Multi-domain Data Center
             Interconnect", draft-fang-actn-multidomain-dci, work in

   [Klee] K. Lee, H. Lee, R. Vilata, V. Lopez, "ACTN Use-case for On-
             demand E2E Connectivity Services in Multiple Vendor Domain
             Transport Networks", draft-klee-actn-connectivity-multi-
             vendor-domains, work in progress.

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   [Kumaki] K. Kumaki, T. Miyasaka, "ACTN : Use case for Multi Tenant
             VNO ", draft-kumaki-actn-multitenant-vno, work in

   [Lopez] D. Lopez (Ed), "ACTN Use-case for Virtual Network Operation
             for Multiple Domains in a Single Operator Network", draft-
             lopez-actn-vno-multidomains, work in progress.

   [Shin] J. Shin, R. Hwang, J. Lee, "ACTN Use-case for Mobile Virtual
             Network Operation for Multiple Domains in a Single
             Operator Network", draft-shin-actn-mvno-multi-domain, work
             in progress.

   [Xu] Y. Xu, et. al., "Use Cases and Requirements of Dynamic Service
             Control based on Performance Monitoring in ACTN
             Architecture", draft-xu-actn-perf-dynamic-service-control,
             work in progress.

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5. Contributors

Authors' Addresses

   Daniele Ceccarelli (Editor)
   Stockholm, Sweden

   Young Lee (Editor)
   Huawei Technologies
   5340 Legacy Drive
   Plano, TX 75023, USA
   Phone: (469)277-5838

   Luyuan Fang

   Diego Lopez
   Telefonica I+D
   Don Ramon de la Cruz, 82
   28006 Madrid, Spain

   Sergio Belotti
   Alcatel Lucent
   Via Trento, 30
   Vimercate, Italy

   Daniel King
   Lancaster University

   Dhruv Dhoddy
   Huawei Technologies

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