TEAS Working Group Daniele Ceccarelli (Ed) Internet Draft Ericsson Intended status: Informational Young Lee (Ed) Expires: November 2015 Huawei June 15, 2015 Framework for Abstraction and Control of Transport Networks draft-ceccarelli-teas-actn-framework-00.txt Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on December 15, 2015. Copyright Notice Copyright (c) 2015 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents Ceccarelli, et al. Expires December 15, 2015 [Page 1] Internet-Draft ACTN Framework March 2015 carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Abstract Transport networks have a variety of mechanisms to facilitate the separation of the data plane and control plane. They also have a range of management and provisioning protocols to configure and activate network resources. These mechanisms represent key technologies for enabling flexible and dynamic networking. Abstraction of network resources is a technique that can be applied to a single network domain or across multiple domains to create a single virtualized network that is under the control of a network operator that may be the customer of the operator that actually owns the network resources. This draft provides a framework for Abstraction and Control of Transport Networks (ACTN). 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.........................................9 3. ACTN architecture..............................................9 3.1. Customer Network Controller..............................12 3.2. Multi Domain Service Coordinator.........................13 3.3. Physical Network Controller..............................14 3.4. ACTN interfaces..........................................15 4. References....................................................17 4.1. Informative References...................................17 5. Contributors..................................................20 Authors' Addresses...............................................20 1. Introduction Transport networks have a variety of mechanisms to facilitate separation of data plane and control plane including distributed Ceccarelli, et al. Expires December 15, 2015 [Page 2] Internet-Draft ACTN Framework March 2015 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. The term Transport Network in this draft refers to any connection- oriented network that has the ability of dynamic provisioning and traffic engineering such that resource guarantees can be provided to the network's clients. Some examples of networks that are in scope of this definition are optical networks, MPLS Transport Profile (MPLS-TP), MPLS Traffic Engineering (MPLS-TE), and other emerging technologies with connection-oriented behavior. 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 compared with 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 . Coordination of resources across multiple domains to provide end-to-end services regardless of whether the domains use SDN or not. 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: Ceccarelli, et al. Expires December 15, 2015 [Page 3] Internet-Draft ACTN Framework March 2015 applied technology, administrative zones, or vendor-specific technology islands) as a single virtualized network. Network virtualization refers to allowing the customers of network operators (see Section 2.1) to utilize a certain amount of network resources as if they own them and thus control their allocated resources with higher layer or application processes that enables the resources to be used in the most optimal way. This empowerment of customer control facilitates introduction of new services and 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 a specific service, the set of consumed resources or to a particular customer. Customer controller of the virtual network is envisioned to support a plethora of distinct applications. This means that there may be a further level of virtualization that provides a view of resources in the customer's virtual network for use by an individual application. 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 Optical Networking Foundation (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 Ceccarelli, et al. Expires December 15, 2015 [Page 4] Internet-Draft ACTN Framework March 2015 mapping, translation, isolation and security/policy enforcement, etc.; This function is often referred to as orchestration. - 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 relationship. A further discussion of the term "abstraction" can be found in [TE-INFO]. 2. Business Model of ACTN The Virtual Private Network (VPN) [RFC4026] and Overlay Network (ON) models [RFC4208] are built on the premise that one single network provider provides all virtual private or overlay networks to its customers. These models are simple to operate but have 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 Ceccarelli, et al. Expires December 15, 2015 [Page 5] Internet-Draft ACTN Framework March 2015 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 service offering is not enough and it is desirable to provide each of them with a customized virtual network service. Advanced customers may own dedicated virtual resources, or share resources. They may also have the ability to modify their service parameters within the scope of their virtualized environments. As customers are geographically spread over multiple network provider domains, they have to interface multiple providers and may have to support multiple virtual network services with different underlying objectives set by the network providers. To enable these customers to support flexible and dynamic applications they need to control their allocated virtual network resources in a dynamic fashion, and that means that they need an abstracted view of the topology that spans all of the network providers. 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 Ceccarelli, et al. Expires December 15, 2015 [Page 6] Internet-Draft ACTN Framework March 2015 +------------------------------------------------------------+ --- | | ^ | 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. 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 as shown in Figure 2 where Service Provider A uses resources from Network Provider A and Network Provider B to offer a virtualized network to its customer. Ceccarelli, et al. Expires December 15, 2015 [Page 7] Internet-Draft ACTN Framework March 2015 Customer X -----------------------------------X Service Provider A X -----------------------------------X Network Provider B X-----------------X Network Provider A X------------------X Figure 2: A service Provider as Customer of Two Network Providers. The ACTN network model is predicated upon this three tier model and is summarized in Figure 3: +----------------------+ | customer | +----------------------+ | | /\ Service/Customer specific | || Abstract Topology | || +----------------------+ E2E abstract | Service Provider | topology creation +----------------------+ / | \ / | \ Network Topology / | \ (raw or abstract) / | \ +------------------+ +------------------+ +------------------+ |Network Provider 1| |Network Provider 2| |Network Provider 3| +------------------+ +------------------+ +------------------+ Figure 3: Three tier model. There can be multiple types of service providers. Ceccarelli, et al. Expires December 15, 2015 [Page 8] Internet-Draft ACTN Framework March 2015 . 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 providers. . 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 infrastructure. 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 ACTN. 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 provisioning. Ceccarelli, et al. Expires December 15, 2015 [Page 9] Internet-Draft ACTN Framework March 2015 . 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 virtual services that are coordinated under ACTN can be split into two categories: . 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 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 Ceccarelli, et al. Expires December 15, 2015 [Page 10] Internet-Draft ACTN Framework March 2015 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 4 below and are the following: . CNC - Customer Network Controller . MDSC - Multi Domain Service Coordinator . PNC - Physical Network Controller Ceccarelli, et al. Expires December 15, 2015 [Page 11] Internet-Draft ACTN Framework March 2015 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 4: 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. Ceccarelli, et al. Expires December 15, 2015 [Page 12] Internet-Draft ACTN Framework March 2015 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. In order to allow for a hierarchy of MDSC, the interface between the parent MDSC and a child MDSC must be the same as the interface between the MDSC and the PNC. This does not introduce any complexity as it is 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. Ceccarelli, et al. Expires December 15, 2015 [Page 13] Internet-Draft ACTN Framework March 2015 +-------+ +-------+ +-------+ | CNC-A | | CNC-B | | CNC-C | +-------+ +-------+ +-------+ \___________ | ___________/ ---------- | ---------- \ | / +-----------------------+ | MDSC | +-----------------------+ __________/ | \_________ ---------- | -----------____ / | \ +----------+ +----------+ +--------+ | MDSC | | MDSC | | MDSC | +----------+ +----------+ +--------+ | / | / \ | / | / \ +-----+ +-----+ +-----+ +-----+ +-----+ | PNC | | PNC | | PNC | | PNC | | PNC | +-----+ +-----+ +-----+ +-----+ +-----+ Figure 5: 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 bounds. 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). 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. 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] Ceccarelli, et al. Expires December 15, 2015 [Page 14] Internet-Draft ACTN Framework March 2015 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. Figure 5 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 5 (ACTN Interfaces) below: Ceccarelli, et al. Expires December 15, 2015 [Page 15] Internet-Draft ACTN Framework March 2015 .-------------- ------------- | | 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 5: 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. . 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 Ceccarelli, et al. Expires December 15, 2015 [Page 16] Internet-Draft ACTN Framework March 2015 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 resources. The interfaces within the ACTN scope are B and C. 4. Manageability TBD 5. Security TBD 6. References 6.1. Informative References [PCE] Farrel, A., Vasseur, J.-P., and J. Ash, "A Path Computation Element (PCE)-Based Architecture", IETF RFC 4655, August 2006. [RFC4026] L. Andersson, T. Madsen, "Provider Provisioned Virtual Private Network (VPN) Terminology", RFC 4026, March 2005. Ceccarelli, et al. Expires December 15, 2015 [Page 17] Internet-Draft ACTN Framework March 2015 [RFC4208] G. Swallow, J. Drake, H.Ishimatsu, Y. Rekhter, "Generalized Multiprotocol Label Switching (GMPLS) User- Network Interface (UNI): Resource ReserVation Protocol- Traffic Engineering (RSVP-TE) Support for the Overlay Model", RFC 4208, October 2005. [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. [TE-INFO] A. Farrel, Editor, "Problem Statement and Architecture for Information Exchange Between Interconnected Traffic Engineered Networks", draft-ietf-teas-interconnected-te- info-exchange, work in progress. [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. Ceccarelli, et al. Expires December 15, 2015 [Page 18] Internet-Draft ACTN Framework March 2015 [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 progress. [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. [Kumaki] K. Kumaki, T. Miyasaka, "ACTN : Use case for Multi Tenant VNO ", draft-kumaki-actn-multitenant-vno, work in progress. [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. Ceccarelli, et al. Expires December 15, 2015 [Page 19] Internet-Draft ACTN Framework March 2015 7. Contributors Authors' Addresses Daniele Ceccarelli (Editor) Ericsson Torshamnsgatan,48 Stockholm, Sweden Email: daniele.ceccarelli@ericsson.com Young Lee (Editor) Huawei Technologies 5340 Legacy Drive Plano, TX 75023, USA Phone: (469)277-5838 Email: leeyoung@huawei.com Luyuan Fang Email: luyuanf@gmail.com Diego Lopez Telefonica I+D Don Ramon de la Cruz, 82 28006 Madrid, Spain Email: diego@tid.es Sergio Belotti Alcatel Lucent Via Trento, 30 Vimercate, Italy Email: sergio.belotti@alcatel-lucent.com Daniel King Lancaster University Email: d.king@lancaster.ac.uk Dhruv Dhoddy Huawei Technologies dhruv.ietf@gmail.com Ceccarelli, et al. Expires December 15, 2015 [Page 20]