Documenting mandatory profile for OI applications

[italobusi]

The YANG model for OI has been updated to allow profiling the YANG model for other applications besides the original OI applications

However, in order to foster interoperability, there is a need to document the mandatory profile for OI applications: the profile should indicate the attributes which are optional in the model because not needed for non-OI applications but are required to support the OI applications

[sergiobelotti]

Here the JSON example about OI application sent by Esther. Thanks Esther!
JSON_OI_example_last_release_ietf.json

[sergiobelotti]

From Esther:

here is the profiling:
The following parameter must be filled in for an accurate optical impairment assessment of paths during path computation. We only focus on those parameters that are needed for impairments computation, but other parameters may also be mandatory depending on the targeted use cases.

In general, [null] must be reported for mandatory data when it is not known. for example an EDFA must report out-voa = [null] if the amplifier is equipped with an out VOA and that its value is unknown. If it is not equipped, then it should not report out-voa.

amplifier OMS-element
must contain a list of amplifier-element. this list can be used to represent parallel (for different frequency range, like multi-band elements) and or cascaded elements (for DGE capable amplifiers). For this purpose stage order and frequency-range are needed. amplifier-elements categories:

a. EDFA amplifier must contain:

type-variety (if different or more precise than the one at amplifier level)
frequency-range
stage-order is mandatory if there are more than one amplifier
element cascaded for the same frequency range
actual-gain
tilt-target
out-voa if the amplifier is equiped with an out-voa
in-voa if the amplifier is equiped with an in-voa
total-output-power
nominal-carrier-power or nominal-power-spectral-density
pdl
and may contain:

name
b. Raman amplifier must contain:

type-variety (if different of more precise than the one at amplifier level)
frequency-range
stage-order is mandatory if there are more than one amplifier
cascaded for the same frequency range
actual-gain
raman-direction
raman-pump
total-output-power
nominal-carrier-power or nominal-power-spectral-density
pdl
and may contain:

name
c. DGE must contain the power targets for each crossing MC

type-variety
stage-order
is-dynamic-gain-equalizer
media-channel-groups
media-channel-group* []
media-channels* []
flexi-n
flexi-m
delta-power
and may contain:

name
Fibers oms-element
Loss of fiber spans should be reported as precisely as possible including the detail of connector fosses of lumped losses if they are known. For this purpose the model provides to element categories: fiber and concentratedloss. The layout of lumped losses should be reported thanks to the index order of each OMS-element and fiber must include:

type-variety
length
loss-coef
total-loss: this must be the result of measurements (e.g. input power - output power measured on both ends thanks to
amplifier power monitor capability)
conn-in if loss of connector is known
conn-out if loss of connector is known
pmd
ROADM
profile of impairments per roadm path (express add or drop) is detailed in C Kelly slides
In addition to this, the target equalization powers are reported per link (OMS). These values must be present:

equalization-mode
nominal-carrier-power or power-spectral-density: represent the target value
media-channel-groups!
media-channel-group* []
media-channels* []
flexi-n
flexi-m
delta-power: represents the deviation between the target
value and this MC #164

[ggrammel]

In case of parallel multi-band amplifiers one can describe the individual amplifiers as proposed, but there is an additional splitter/combiner element that needs to be modeled. Suggest to re-phrase:

amplifier OMS-element
must contain a list of amplifier-element. this list can be used to represent parallel (for different frequency range, like multi-band elements) and or cascaded elements (for DGE capable amplifiers).

amplifier OMS-element
must contain a list of amplifier-element. this list can be used to represent parallel (for different frequency range, like multi-band elements) and or cascaded elements (for DGE capable amplifiers). In case of multi-band elements, splitters and combiners are modeled as separate entities outside the OMS-element.

[egriseri]

@ggrammel your commment is a good point: it looks as if we missed the splitters and combiners. However I'd prefer to model them inside the OMS-element as they are actually an essential part of a multi-band amplifier. Thus we can

1. Model them explicitly as a part of the OMS-element
2. Model them implicitly by considering their effect on the NF and gain of the amplifiers (one for each band)

what others think?

[italobusi]

@ggrammel your commment is a good point: it looks as if we missed the splitters and combiners. However I'd prefer to model them inside the OMS-element as they are actually an essential part of a multi-band amplifier. Thus we can

1. Model them explicitly as a part of the OMS-element
2. Model them implicitly by considering their effect on the NF and gain of the amplifiers (one for each band)

what others think?

If I recalled well, we have discussed this point and agreed for option 2

Could you please check whether this is properly documented in the I-D text and/or YANG descriptions?

[sergiobelotti]

@italobusi @egriseri: I've also have some reminds about this discussion and decision for option 2, that was also the chosen option also in other cases of our model, e.g. for protection exploiting OI in the connectivity matrix. But we have not documented in the I-D this decision . Take into account DGE section is still to be completed with text in issue #153 and so we can add also this decision in the context of update for IETF119. Is it enough the text provided by Enrico or we should elaborate more ?