1. TOSCA NFV profile: short vs long-term approach
Michael Brenner, GigaSpaces
Li Shitao, Huawei
July 5, 2017

2. Issues that cannot be rapidly reconciled
Principles that conflict at time:
Responsibility (to ETSI NFV) to make the NFV profile match closely 1:1 the ETSI NFV model
Responsibility (to overall TOSCA users community) to maintain the TOSCA Simple YAML philosophy and extend the spec, rather than off an NFV branch
Weighing in favor of a) above has created an unhealthy “split” in the TOSCA community:
The main SimpleYAML thread supporting Enterprise/IT
The NFV profile supporting Telco/NFV
The consequence is complexity and difficulties for TOSCA parsers and in particular TOSCA orchestrators because of partial duplication of concepts modelled differently

3. Proposal to address the issue
Long-term: take a step back to re-group and produce an NFV profile completely based on and inheriting from the TOSCA Simple YAML to support a more generic/combined Enterprise/IT & Telco/NFV approach, leveraging industry adoption:
Use feedback from Open Source communities (e.g. ONAP)
Align with existing model as defined in TOSCA Simle YAML (e.g. using TOSCA normative types)
Result may not perfectly match ETSI NFV VNF model, but meet requirements
Result to address other features needed in SimpleYAML (e.g. support for EPA)
Discussions are starting with the SimpleYAML principals to gain support
Short-term: NFV profile matching ETSI VNF model can be achieved, but it may be a temporary solution
NFV profile shall include ALL and ONLY those TOSCA types that support mapping closely to ETSI NFV VNF model
Types that have a matching/overlapping equivalent in TOSCA Simple YAML should be marked/categorized appropriately
Drawback: there is a risk that the long-term proposal may not be able to ensure backward compatibility to some of the types in the short-term spec

4. Recommendation
We would like to obtain ETSI NFV support for the long-term proposal:
a single TOSCA spec that can address both Telco and Enterprise requirements will ensure the ability to ride industry developments in automation
a dedicated, isolated TOSCA-like spec for NFV may not have adequate or soon enough implementations, or the choices may be scarce
If the current ETSI NFV SOL001 direction must be continued in order to provide a spec matching very closely the ETSI NFV IFA information, we recommend SOL001 to take over the current tosca-nfv-profile-csd04 spec and complete the work within ETSI NFV
This will allow TOSCA TC & NFV ad-hoc group to focus on the long-term proposal
Long-term: TOSCA TC and TOSCA NFV ad-hoc to make efforts to deliver a new a new version of tosca-nfv-profile that addresses the ETSI NFV IFA model requirements, but consistent with the overall SimpleYAML evolution
Efforts to minimize backward incompatibility with current NFV profile (if continued)
Timeline TBD