The purpose of this document is to define use cases and requirements for the provisioning and life cycle management of Resource Functions (RF). Examples of RFs are VNFs and Network Services (as defined in ETSI NFV), Service Functions and Service Function Chains (as defined in IETF), and physical network functions such as routers and Content Delivery Networks (CDNs). The use cases and requirements are intended to drive the definition of an associated TM Forum API.
The use cases and requirements are divided into two basic kinds, i.e., intent-based and detailed-based. In the case of intent-based, the consumer does not have a view or the ability to directly affect the components of a given entity. For the detailed-based, the opposite is true.
Very generic terms are used for the actors in the various use cases, e.g., Resource Function Consumer and Resource Function Provider. Definition of a functional block architecture, such as ETSI NFV reference architecture framework is avoided, since reference architectures can lead to misinterpretation where the functional blocks are seen as system boundaries and typically limit the possible use of a given API. This in turn leads to very slow and contentious standardization. The view taken in this document authors is to first define use cases and requirements for an API, and then (as needed) profile / specialize the API for a given reference point.
The various operations in the associated API can be packaged in various ways to suit product needs. However, not all subsets of operations may make sense for a given product. In the end, what subset of operations to use is an implementation decision to be made by the user of the API associated with the use cases and requirements in this document.
TR225 has several associated documents, i.e.:
TR255A Connectivity Patterns for Virtualization Management (this was previously released as IG1147)
TR255B Specification Requirements for Resource Functions
TMF664 Resource Function Activation and Configuration API