1. TAPI Photonic Media Model
Stephane St-Laurent, Infinera
May 7, 2019
Updated V2

2. Purpose of this contribution
Explain the Photonic Media define in TAPI
Expose some of the elements that need to be define/augmented

3. Definition: PHOTONIC_LAYER_QUALIFIER
PHOTONIC_LAYER_QUALIFIER_MC:
Media Channel (MC): continuous optical spectrum between end points in the photonic layer intended to transport OTSi
PHOTONIC_LAYER_QUALIFIER_MCA:
Media Channel Assembly (MCA): a group of media channel managed as a single entity
PHOTONIC_LAYER_QUALIFIER_OTSiMC:
OTSi Media Channel (MC): Continuous optical spectrum between end points in the photonic layer to represent the optical spectrum intended to be used by a signal from an OTSi
PHOTONIC_LAYER_QUALIFIER_OTSiMCA:
OTSi Media Channel Assembly (MCA): a group of OTSi media channel managed as a single entity
PHOTONIC_LAYER_QUALIFIER_OTSi:
Optical Tributary Signal: optical signal
Network Medial Channel (NMC): continuous optical spectrum between end points in the photonic layer to represent the optical spectrum intended to carry a signal from an OTSi
Service Media Channel (SMC): continuous optical spectrum between end points in the photonic layer obtain through optical filter that serve NMC (optionally SMC)
Assembly: group of media channel (Network or Service Media Channel) managed as a single entity

4. Overview Media Channel (MC) OTSi Media Channel (OTSiMC)
Continuous optical spectrum define by lower and upper frequency
Could be aligned on ITU grid (could be 6.25 GHz)
Could Include guardband (could be 6.25 GHz and it is technology dependent)
MC could contain 0 to n OTSiMC
MC could be requested at a domain level to represent the contiguous spectrum offered by an optical domain
OTSi Media Channel (OTSiMC)
Continuous optical spectrum to represent the optical spectrum intended to be used by an OTSi
Define by lower frequency and upper frequency
Do no require to be aligned to ITU grid but are technology dependent (medial channel power monitor and transmitter capability)

5. Media Channel (MC)
A media channel (MC) is a spectrum-band define between its lower-frequency and its upper-frequency (in MHz)
It could expose guard bands (read only), a lower-guardband and an upper-guardband, that represent a filter specification (will be define later)
The constraint apply to the possible value for the lower and upper frequency

6. OTSi Media Channel (OTSiMC)
An OTSi media channel (OTSiMC) is a spectrum-band define between its lower-frequency and its upper-frequency (in MHz)
It represent the optical spectrum intended to be used by a signal from an OTSi, for such, it need to be define in the context of a media channel
It is use to provide information to a system to:
measure power
detect the presence of signal
allocate possible OTSiMC in an MC
The constraint apply to the possible value for the lower and upper frequency

7. OTSi
An OTSi is a signal define at a specific center-frequency (in MHz)
It is bounded by its lower-frequency and upper-frequency (in MHz)
The constraint apply to the possible value for the lower and upper frequency

8. OTSi and OTSiMC correlation
An OTSi is a signal define at a specific center-frequency (in MHz) based on the constraint and accuracy associated to a transmitter
The measurement of the power at the OTSiMC need to correlate with the measurement done at the transponder
For such, the OTSiMC spectrum-bandwidth should be used in both measurement

9. Multiple OTSiMC in an MC
When multiple OTSi could be contain inside one MC, a user should be able to pass information so the OTSiMC could be adjacent, or with some spacing, to each others
Adding some spectrum spacing could improve OSNR of the signal
Note: This provides to the Path Computation Engine (PCE) the information needed to allocate the center frequency to the OTSiMCs. The PCE must still maintain the constraint associated to the center-frequency that is defined by the transponder (OTSi) specification

10. Multiple OTSiMC in an MC
Spacing between OTSiMC could be passed using OTSiMC-additional-spectrum or non-adjacent-OTSiMC-spectrum. One parameter need to be agree on. The non-adjacent-OTSiMC-spectrum give a better understanding to evaluate non linear impairment (NLI).

11. Center Frequency Constraint to OTSiMC
The OTSiMC center-frequency constraint associated to the center frequency are associated to the adjustment-granularity
The 2 examples on the left show case of granularity of 25 or 12.5 GHz
It is all associated to the equation:
n * adjustment-granularity
Need to add center-frequency constraint in connectivity-service

12. Connectivity Service
Hierarchical

13. #1: MCA with 1 MC and 1 OTSiMCA and 2 OTSiMC
Simple case
Declarative model
All the parameter are provided in an absolute value

14. #2: MCA with MC(s) and 1 OTSiMCA for 4 OTSiMC
More Complex
Use Intend with constraint
1 MCA
Use topology constraint
2 MC
1 OTSiMCA
OTSiMC = 36.5 GHz (Must)
non-adjacent-OTSiMC-spectrum >= 37.5

15. #3: MCA with 1 OTSIMCA with 4 OTSiMC
Update: New
PCE followed by C.S. to 2 domains
Use Intend with constraint
1 MCA
Use topology constraint
1 OTSiMCA
Must route together
OTSiMC = 36.5 GHz (Must)
non-adjacent-OTSiMC-spectrum >= 37.5
First call to PCE
Top SDN
Second call to both lower level SDN

16. #1: connectivity-service (needed)
Updated details
Declarative model
1 operation
Very simple

17. #2: connectivity-service (needed)
Intent base
1 operation
To the connectivity services
The user know the constraint associated to the transponder
The user want spectrum optimization
Could have call the PCE before an know that there are chunk of GHz available

18. #3: PCE and connectivity-service (multi-layer)
Update: New
Intent followed by Declarative
Involve Top SDN and 2 lower-level domain SDN without PCE capability
Must be able to retrieve the spectrum allocation for the second call from the PCE of the top SDN
1 To 1 mapping is easy when the PCE return include MCA/MC/OTSiMCA/OTSiMC directly
Need to augment PCE to do more then just path only function
First call to PCE
Top SDN
to C.S. Domain #1 and Domain#2

19. Transponder Use Case

20. Disaggregated Use Case: Single OTSi per interface
The OTSiG could contains 1 or multiple OTSi
The OTSiG could be provided to the ROADM using multiple interface

21. Disaggregated Use Case: Multiple OTSi per interface
The OTSiG could contains 1 or multiple OTSi
The OTSiG could be provided to the ROADM using multiple interface
Each interface could contains multiple OTSi

22. Disaggregated: Transponder/ Photonic
The OAM channel need to use the OCN and have an OCC between the photonic NE and the Transponder
Needed:
Interface and Protocol to manage:
OTSi TxTransmitPower
OTSi CentralWavelength (For restauration handle by Photonic SDN)
Enable/Disable ???
And to Retrieve Capabilities:
OTSi TxTransmitPower range
OTSi CentralWavelength Tuneability (Range [ lowerFreq,upperFreq]) in MHz