1、ATIS-0200013 ATIS Standard on Inter-Administrative Domain NFV Technical Requirements Alliance for Telecommunications Industry Solutions Approved March 8, 2016 Abstract A number of multi-administrative domain Network Functions Virtualization (NFV) use cases have been documented in ATIS-0200012. These
2、 use cases are highly relevant to the needs of wireline, wireless, cable, and enterprise networks. Based on these use cases, this document establishes a high level architecture and associated requirements to enable new business opportunities based on open standards to the communications industry. AT
3、IS-0200013 ii Foreword The Alliance for Telecommunications Industry Solutions (ATIS) serves the public through improved understanding between carriers, customers, and manufacturers. The Network Functions Virtualization Forum (NFV Forum) provides the inter-provider technical requirements and solution
4、s to help ICT companies realize the benefits of rapidly advancing software-defined networking and NFV technologies. This work is part of a sweeping evolution that is moving the industry from integrated, hardware-centric solutions to modular, hardware-agnostic frameworks by abstracting the hardware r
5、esources into a consistent operating environment for the software. The mandatory requirements are designated by the word shall and recommendations by the word should. Where both a mandatory requirement and a recommendation are specified for the same criterion, the recommendation represents a goal cu
6、rrently identifiable as having distinct compatibility or performance advantages. The word may denotes an optional capability that could augment the standard. The standard is fully functional without the incorporation of this optional capability. Suggestions for improvement of this document are welco
7、me. They should be sent to the Alliance for Telecommunications Industry Solutions, NFV Forum, 1200 G Street NW, Suite 500, Washington, DC 20005. At the time of consensus on this document, the NFV Forum, which was responsible for its development, had the following leadership: Tom Anderson, NFV Co-Cha
8、ir (Cisco) Ben Campbell, NFV Co-Chair (Oracle) ATIS-0200013 iii Table of Contents 1 Executive Summary . 1 1.1 Scope . 1 1.2 Assessment and Conclusions 1 2 References . 1 3 Definitions, Acronyms, Use Cases.3NIST 800-145, Special Publication 800-145, The NIST Definition of Cloud Computing.43 Definitio
9、ns, Acronyms, in other cases one producer administrative domain may offer the service function with additional extensions. As such, the CAD is delivering an end-user service with assistance from one or more PADs. This may be implemented specifically in at least two different ways: A CAD may choose n
10、etwork service functions from a catalog of available service functions in one or more PADs, and/or A CAD may instantiate its own network service function in a PAD. In this case, the service function in the PAD is a tenant environment that is offered to and consumed by the CAD. We term this case the
11、use of an “NFV Infrastructure Capability” in the PAD. This terminology can be applied to the use cases documented in ATIS-0200012. For example: Table 1: Example CAD and PAD Roles for Candidate Use Cases USE CASE CONSUMER ADMINSTRATIVE DOMAIN (CAD) PRODUCER ADMINISTRATIVE DOMAIN(s) (PAD) 4.1 Virtual
12、Network Operator Virtual Network Operator that is consuming service functions located in facilities based access or transit operators or 3rdparty VNF hosting providers. Facilities based access or transit operators 3rdparty VNF hosting providers 4.2 Cooperative Cloud-Based CDN Arrangements CDN provid
13、er that is consuming a tenant service in the access Network Service Providers network. Access Network Service Provider provides a tenant environment close to the network edge with optional APIs for the CDN to acquire network and subscriber information. 4.3 Virtualized Content Delivery Across Multipl
14、e Access Domains Centralized CDN entity. Access Network(s) 4.4 Roaming Home Service Provider that is consuming service functions in, or close to, the visited network to facilitate home services. Visited Network Service Provider or a local 3rdparty hosting service offering service functions or a tena
15、nt environment to the home provider. 4.5 Efficient Home Routed VoLTE Roaming Arrangements Home Service Provider that (for example) may be consuming a tenant service function in the visited network or 3rdparty hosting service local to the visited network. Visited Network Service Provider 3rdparty hos
16、ting service 4.6 Efficient Enterprise Voice/Collaboration Arrangements Enterprise that (for example) may be consuming a tenant service function in the network service providers network to gain real time and/or QoS advantages. Network Service Provider offering service functions or a tenant environmen
17、t to the Enterprise. ATIS-0200013 5 USE CASE CONSUMER ADMINSTRATIVE DOMAIN (CAD) PRODUCER ADMINISTRATIVE DOMAIN(s) (PAD) 4.7 Enabling Service Function Chains with Third Party VNF Application Providers Network Service Provider that may be consuming 3rdparty service functions. Network Functions Servic
18、e Provider(s) offering access to a suite of VNFs for use by a Network Service Provider 4.8 Enabling Third Party VNF Applications 3rdParty Application Providers Network Service Providers offering access to network service functions to allow application developers to create new network-assisted applic
19、ations. 4.1 Inter-Administrative Domain NFV Service Models Administrative domains can interwork relative to cloud services in a variety of ways. For example, NIST 800-145 discusses three specific service models: Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Serv
20、ice (IaaS). SaaS refers to the capability provided to a consumer administrative domain to use a producer administrative domains service functions running on a cloud infrastructure. With SaaS, the consumer administrative domain does not manage or control the underlying cloud infrastructure including
21、network, servers, operating systems, storage, or even individual application capabilities. However, the consumer administrative domain would likely be able to specify some sub-set of service function configuration settings. PaaS refers to the capability provided to a consumer administrative domain t
22、o deploy onto the cloud infrastructure consumer-created or acquired service functions created using programming languages, libraries, services, and tools supported by the producer administrative domain. As with SaaS, the consumer administrative domain does not manage or control the underlying cloud
23、infrastructure including network, servers, operating systems, or storage, but would likely manage configuration settings for the service functions. IaaS refers to the capability provided to the consumer administrative domain to provision compute, storage, networking, and other fundamental computing
24、resources where the consumer administrative domain is able to deploy and run arbitrary software, which can include operating systems and service functions. The consumer administrative domain does not manage or control the underlying cloud infrastructure but has full control and life cycle management
25、 responsibilities for the service functions that it may choose to deploy onto the infrastructure. ETSI GS NFV 001 V1.1.1 also references these different service models in use cases #1, #2, and #3 (discussed in sections 5, 6, and 7 respectively). In subsequent sections, these models, which ETSI calls
26、 “use cases“, are referred to as “NFV Service Models“ to distinguish them from the use cases defined in ATIS-0200012. ETSI Use Case #1, Network Functions Virtualization Infrastructure as a Service (NFVIaaS), is an IaaS model that allows a consumer administrative domain to run VNF instances on the NF
27、VI controlled, i.e., an NFV infrastructure capability, provided by the producer administrative domain. ETSI Use Case #2, Virtual Network Functions as a Service (VNFaaS), is an SaaS model that allows a consumer administrative domain to chain one or more VNFs managed by a producer administrative domai
28、n in the creation of a larger service or application delivered to its end customers. As is typical of SaaS models, the consumer administrative domain does not manage or otherwise control the VNF(s) though it may be able to provision certain VNF configuration parameters. ETSI Use Case #3, Virtual Net
29、work Platform as a Service (VNPaaS), is a PaaS model that allows a consumer administrative domain the flexibility of more complex combinations of NFVIaaS and VNFaaS. VNPaaS is similar to VNFaaS except in scale and control of the VNFs. Additionally, VNPaaS may also provide the capability for the cons
30、umer administrative domain to offer its own VNF instances (NFVIaaS) within the platform. VNPaaS provides a larger scale service function with much more control by the consumer administrative domain. ATIS-0200013 6 4.2 Inter-Administrative Domain Architecture Multi-administrative domain use cases may
31、 include multiple producer and multiple consumer administrative domains. Specifically, a consumer administrative domain can utilize service functions in one or more producer administrative domains. Similarly, a producer administrative domain may offer service functions or NFV infrastructure capabili
32、ties to multiple consumer administrative domains. To simplify these relationships, we model these cases as a pairwise combination of one consumer and one producer administrative domain. This model can be scaled appropriately to address most multi-domain scenarios. Figure 4.1 shows the architecture o
33、f a pairwise consumer/producer use case. Each administrative domain implements network functions, services, and applications within a virtualization environment. Although we commonly assume the use of NFV as the virtual environment, the interfaces and procedures between the administrative domain can
34、 apply to any suitable virtualization environment. The Service Management Gateway abstracts the details associated with the virtualization environment from the interface between the two administrative domains. The Service Management Gateway in the producer administrative domain: Advertises and expos
35、es the service function catalog of the producer administrative domain to potential consumer administrative domains. Enables a consumer administrative domain, based on policies, to select one or more service functions from the service function catalog. Supports service function activation for the sel
36、ected service functions. Enables the consumer administrative domain to provide configuration and service life cycle management functions as defined by the service function catalog. The Service Management Gateway in the consumer administrative domain enables the consumer administrative domain to: Vie
37、w the service function catalog of producer administrative domains; Select one or more service functions within the catalog; Activate selected service function(s); Provide configuration and service life cycle management directives as allowed by the service function catalog. The Service Management Gat
38、eways communicate via the IAD-S interface. The IAD-S interface provides a secure interface between administrative domains to support the above named functions. The IAD-O interface exists between administrative domains to support the exchange of fault and performance data to allow the consumer admini
39、strative domain to monitor reliability and performance aspects of the selected service functions. Information exchanged over this interface supports service level agreement (SLA) compliance for the selected service functions and may also be used to invoke service life cycle management functions that
40、 may (for example) increase or decrease the capacity of the specific service functions. The IAD-CD interface represents service specific control and data interfaces required to support the selected service functions. Since this interface or set of interfaces is service function specific, the IAD-CD
41、interface is not specifically defined in this specification. However, information required to establish, monitor, and tear down service function specific interfaces must be included in the service function catalog. ATIS-0200013 7 4.3 Application of NFV Service Models to the Inter-Administrative Doma
42、in Architecture Different modes of inter-administrative domain NFV are possible depending on the NFV Service Model and the nature of the functions being virtualized. Depending on the mode of operation, different scenarios exist for how the service function software is provided and configured. The NF
43、V Service Models are introduced in section 4.1. Different levels of standardization may apply to service functions. At one extreme, some service functions may be fully standardized and simply referring to their standard definition will allow the producer administrative domain to select suitable soft
44、ware for the virtual machine. At the other extreme, the producer administrative domain may just provide an NFV infrastructure capability and the software is provided by the consumer administrative domain. This section discusses the main modes of interest and their characteristic features. 4.3.1 Netw
45、ork Functions Virtualization Infrastructure as a Service (NFVIaaS) In the NFVIaaS NFV Service Model, the Service Functions are defined by the consumer administrative domain. In this mode the consumer administrative domain must specify the characteristics (e.g., performance requirements) of the infra
46、structure but does not inform the producer administrative domain about the precise nature of the service function that will be run. The consumer administrative domain is able, in real time, to load its own software onto the infrastructure provided by the producer administrative domain. The consumer
47、administrative domain is responsible for the management and configuration of this service function. In order to do this, the consumer administrative domain must interact with the MANO system in the producer administrative domain. This may be done by providing suitable interfaces from the producer ad
48、ministrative domains existing MANO system or by allowing the consumer administrative domain to add its own software functions to the MANO. Figure 4.1 Inter-Administrative Domain Architecture ATIS-0200013 8 4.3.1.1 Management and Orchestration for Lifecycle Management The PAD must expose not just the
49、 NFVI to the CAD but also sufficient MANO capabilities to allow the CAD to perform lifecycle management. In practice this mode could be regarded as NFVI plus VIM as a Service. Within this mode, multiple management and orchestration options exist relative to the VNF life cycle management. Three of the most interesting options are outlined below. Option 1 CAD has control of VIM The CAD is provided controlled access to the VIM for a specific set of resources. This will be in the form of an inter-administrative domain Vi-Vnfm interface (IAD-Vi-Vnfm). T
