[Teas-ns-dt] definitions section 4 improvement discussion

[Kiran Makhijani <[e-mail]>]

Hello,
Thanks for converging on improvement on most of the text. A little more discussion is necessary:

  1.  Can an SLO confidence be 100%?

I was bit confused with this discussion. Most comments were that there is no such thing as 100% confidence but I am not convinced. Is it possible to specify a slice by saying SLO1: guarantees of resource such as bandwidth (Say X mbps) with 100% confidence and SLO2: availability 99.999%? - I hope the answer is Yes. Right?

Another context for 100% confidence context is (Luis also raised this) when NF or SF resources are asked for, they should be seen as virtual but allocated (100%) resource with the guarantee of compute or memory requirements - i.e. without having to contend with another traffic. (confidence sounds bit odd here, but that's what we are using to replace resolution or isolation).

  1.  Dealing with failures:

I am little worried about how we are mixing up the avoidable, recoverable and non-recoverable failures. I did not agree that fan-failure faults are same as congestion. In case of congestion - it must be avoided by minimizing or penalizing other less-critical traffic - because a transport slice asked for this. In case of recoverable HA or failover should kick in. finally non-recoverable are multiple faults:- both active and failover links saw problems and it is impossible to send any traffic. In transport slices, we can specify enough to prevent avoidable and recoverable failures. For example, consider a critical-service transport slice and what must be done to provide disruption free and always-on, and reliable service?

  1.  Monitoring in the context of measurable SLOs:

Jie raised an interesting comment on directly measurable attributes. Many SLOs will require different means of monitoring.  We have not discussed this as a characteristic of a transport slice. Should customer specify any monitoring as part of the transport slice? Perhaps not, but then there is a mention of "monitoring thresholds" in framework document in 3.3. We should have corresponding text in the definition.

Regards
Kiran