1. Photonic Model (ONF Share)
Stephane St-Laurent
June 6, 2018 (V9)

2. Scope
Provide background slides to define photonic model in context of TAPI
Provide some feedback from work done in Facebook TIP (Service Media Channel Connection)
Use some of the OpenROADM Terminology to define the different node type (ROADM, Degree, Share Risk Group Add/Drop (SRG))

3. Single Span (C&L) Media Channel

4. Multiple Span (C&L) Media Channel

5. Fixe Filter (AWG): Band Media + Service MC
OTSi of 37.5G signal
200G AWG
100G AWG
Band Media Channel only in the node (Asymmetric)
Media Channel can contain media channel

6. Programmable Filter (WSS)
OTSiG could be using multiple Service Media Channel. The group of SMC is an SMCG

7. Media Channel containment
Use 2 OTSi per port since combined before WSS (either at the transponder or at the OLS)
Media Channel can contain Media Channel
OTSiG could be using multiple Service Media Channel

8. Band Media Channel Connections (Optical Network Configuration)
between nodes
(OSC, OTS, OMS)
Media Channel
between nodes
(OSC, OTS, OMS)
Band Media Channel Connection

9. 2 Layers (OTSiA and Service Media Channel)
OTSiA is associated to OTSi signal spectrum connection and the relevant OAM
Band Spectrum (or Service Media Channel (SMC)) is associated to optical spectrum used to support one or multiple NMC signal
Optical spectrum could be set (and potentially validated) before the existence of the OTSiA
An SMC group is a list of SMC to support an OTSiG connection. This could provides a one- to-one association between OTSiG and SMCG
In fact, it will be very desired to have mandatory one-to-one association

10. Definition (Service Media Channel - SMC)
Service Media Channel (MC)
Continuous spectrum bandwidth define by lower and upper frequency
Could be aligned on ITU grid (could be 6.25 GHz)
Include guardband (could be 6.25 GHz and it is technology dependent)
SMC are indivisible when using WSS technology (port to port where the NMC have to be routed together)
SMC could contain 0 to n NMC
SMC could be requested at a domain level to represent the contiguous spectrum offered by an optical domain
Network Media Channel (NMC)
Continuous spectrum bandwidth used to represent the signal component generated by an optical transmitter
Define by center frequency and width
Do no require to be aligned to ITU grid but are technology dependent (channel power monitor and transmitter)
NMC have to be routed together (have to go to the same port when using WSS technology)
Could not overlap guardband

11. Why Service Media Channel with multiple NMC?
Topology
Single ( 1 NMC per SMC)
Spectral
Efficiency
Same as Fixed Grid
Routing
SMC could be added or dropped from any port ( any SRG to any SRG port)
Usage
Network with predominant mesh traffic pattern
Multiple (N x NMC per SMC)
Improved spectral efficiency compared to fixed grid
(could be 12.5/37.5 = 33%)
SMC are routed from A to Z in the network with all their contained NMC
Point-to-point DCI, Network with multiple traffic sharing the same co-routed A to Z end-point, Multi-carrier Transmitter

12. OTSiA and Service Media Channel (Separation)
T17-SG TD-WP3-0125!R1!MSW-E (Draft G.Media Discussion)
6 Functional architecture of optical media
The functionality of the optical media consists of constructs that can carry/propagate optical signals as well as elements that can operate on optical waves (e.g., filters). A key result of arranging and configuring these elements is the construction of network media channels, each of which can support an OTSi. The structure of an optical media network is provided in Figure 6-1 below.
[Editor note: needs further review.]
Optical tributary signals (OTSi) are each characterized by their central frequency and an application identifier (see [ITU‑T G.698.2]). The OTSi is depicted by the optical signal modulator/demodulator, as shown in Figure 5‑1.
Below the OTSi are the media constructs that provide the ability to configure the media channels (see clause 7.1.2). The nominal central frequency and width of a media channel is defined by its frequency slot (as defined in [ITU‑T G.694.1]). Each OTSi is guided to its destination by an independent network media channel.
Media channels must be configured before any OTSi can be carried. The effective frequency slot of a media channel is defined by the filters that are in the path of the media channel. The effective frequency slot may be sufficient to support more than one OTSi.
The media constructs and media element are described in clause 7, the OTSiA is described in clause 10.
An application identifier includes the application codes defined in the appropriate optical system Recommendations, as well as the possibility of proprietary identifiers. The identifier covers all aspects of the signal, including forward error correction, baud rate and modulation type.
A media channel that may carry multiple OTSi may be used to provide what is commonly called an "express" channel.
8.1 Assignment of signals to media channels
A media channel may be configured before it has been decided which OTSi will be allocated to it. As described in clause 7.1.2 the OTSi must be compatible with the network media channel that has been assigned.

13. Separation 10.1 Management of OTSiA connections
T17-SG TD-WP3-0125!R1!MSW-E (Draft G.Media Discussion)
10.1 Management of OTSiA connections
From a management control perspective, a request to carry an OTSiA should be considered as a single action. This action involves the configuration of the OTSi modulator and demodulator, the network media channels and the OTSiG‑O. Configuration of the network media channels includes the configuration of the media elements that encompass the media constructs (e.g., media subnetworks, As described above, the network media channel may be fully or partially configured before the OTSiA connection request is received.
flexible grid capable filters and possibly amplifiers) that are part of the serial concatenation of media channels that forms the network media channel.
Two simple cases for the configuration of a network element that includes a media subnetwork when an OTSiA connection request is received are described below:
1) Pre‑configured media elements: In this case the media channels in the media subnetwork and the associated filters are configured before the OTSiA connection request is received:
• The OTSiG‑O connection function and the OMS‑O MSI are configured.
• The media channel(s) in media subnetwork must be checked to verify that the correct ports are connected so that all members of the OTSiG are directed to and or from the same OMS media port. The associated filters are checked to ensure that frequency slot of each filter is compatible with the frequency slot requested for each OTSi.
• In general when the OTSiA is deleted, only the OTSiG‑O connection and OMS‑O MSI (for that OTSiG) should be removed, the configuration of the media elements should not be changed.
or:
2) The media elements are not configured:
• In this case, the media channels in the media subnetworks and filters are configured as a result of the OTSiA connection request. The media channels in the media subnetwork and the associated filters, the OTSiG‑O connection and the OMS‑O MSI are configured. The consistency checks described above should be performed.
• In general, deletion of the OTSiA should also result in the deletion of the OTSiG‑O connection the OMS‑O MSI. The media subnetwork and filter media channels should also be deleted, except in the case where a media channel is being used to support another network media channel.

14. Use Case: OTSiG Combined in Transponder into 1 Link
OTSi are combined in the transponder
A single pin could received multiple NMC (OTSi)
This provides an opportunity to allocate both NMCs inside 1 SMC
OTSiA use SMCA
SMCA is the SMCG and associated overhead of the connection

15. Use Case: OTSiG Combined in ROADM
OTSi are combined in the ROADM using coupler
Combiner provides the ability to built one SMC that contain multiple NMC
OTSiA use SMCA
SMCA is the SMCG and associated overhead of the connection

16. Use Case: OTSiG and WSS
OTSi are in independent Service Media Channel because a Wavelength Service Switch(WSS) can only make a connection to a single system port
OTSiA is a group of 2 NMC that are included into an SMCA composed of a group (SMCG) of 2 SMC

17. Disaggregated: Transponder/ Photonic
The OAM channel need to use the OCN an 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

18. Service Media Channel (Basic View of the stack)
MC Pool (Media Channel Pool):
Spectrum that could be split into different group using filter (static or dynamic)
Some MC Pool have link (OMS/OTS), MC Pool for the NMC are internal
The service media channel (SMC) contains the continuous spectrum associated to the NMC service. It is not divisible.
SMC contain the spectrum of associated NMC, NMC could be added/removed

19. In Line Amplifier (Between OMS)
The CEP of the Band OTS-C provides the TTP and CTP.
The TTP is associated to the OTS-O
The CTP is associated to the OTSME (OPM) and the optical spectrum that it represent

20. In Line Amplifier (Between OMS) (C+L) model 1
Failure of an L-band EDFA should not cause a defect of the OTS but of the OTS-L
The Fiber is used for 2 optical spectrum (C and L), This should be an Implementer Agreement (a.k. ITU Sup. Or MEF L0)

21. In Line Amplifier (Between OMS) (C+L) model 2
Provide monitor point for the C+L signal

22. ROADM Node: Express connection
Could be multiple connections

23. ROADM Node: Express Connection

24. ROADM Node: Express connection Node Detail (Degrees)

25. Degree model using WSS
A Terminal Optical node is the starting point of Optical Spectrum Bandwidth that is defined to support NMC (OTSi signal)

26. Dealing with Combiner and Splitter
Use FC to represent the connectivity of static filter
SMC FC can contains NMC FC
Media Channel can contain other media channel
The wide band of the static filter could contain SMCs

27. Degree (WSS) and SRG (Filter)
ROADM Node use SMC layer (server of NMC)
OTSiA can be supported by multiple SMC
Show stack of the trib port and stack of the line port

28. Degree (WSS) and SRG (Combiner/Splitter)
Do we need OTSiA at the node level (ROADM)

29. Degree (WSS) and SRG (Combiner/Splitter)

30. Question How do we place OTSiA and Network Media Channel together?
Do we define OTSiA layer and another layer for the photonic
Use Inverse muxing model (it is a group that we want to represent)
ITU model show “coordination”

31. SMC and NMC (Disaggregated model)
In a Disaggregated model, the transmitter are independent to the Optical Transport Network (Open Line System)
The Controller want to create SMC service that could carry OTSi in NMC
SMC/NMC could have their own OAM
At least for monitoring of SMC
SMC-O or SMCG-O, if using one-to-one relation with OTSiA, then it is redundant (OTSiA and SMCA are the path representation in the ITU Photonic OAM
If not one-to-one, then a stacking will be needed at the edge of the photonic network (OTSiG-O/SMCG-O/OMS-O/OTS-O) but not after (SMCG-O/OMS- O/OTS-O). Path Failure could be pass from share SMCA to OTSiA.
OTSiA could have relation to a group of OTSi and NMC id
SMCA could have relation to a group of SMC id

32. SMC Group Could create SMC Group Group C = C1+C2
Could be used to correlate to OTSiG in one-to-one relation with SMCG
Facebook TIP YANG Model
Connection are a list of SMCG
SMCG contain a list of SMC
SMC contain List of NMC

33. SMC Group Group are floating Contain 0 or n SMC
Could force that SMC connection could not be created directly, always require a group connection
Group has no relation to spectrum, SMC has
For OAM, could be placed on SMC an have reference to lower and upper frequency

34. SMC Group How to represent group in TAPI?
Group are floating, they do not use resource directly

35. SMC Group (model 1) SMC Group are floating
Do not take resource from pool
SMC use the resource from pool
SMC could not be created without SMCG
The pool allow creation of group
When SMC are created, it allocate usable spectrum for SMC from the pool

36. SMC Group (model 2) Direct containment
How to allocate resource from the MC pool when the spectrum is taken by the Band SMC that reside on top of it?
Could the creation of Band SMC trigger update of the status of the MC pool at the OMS-C Link layer?

37. SMC Group (model 3) (Express)
Use an SMCG Pool to represent a group of SMC
Define a Group Pool
Resource of the MC pool, at the OMS signal level, are taken from the Band SMC
At the end, we need a list of SMC connection with [lowerFreq,upperFreq] in MHz

38. SMC Group (model 3) (Add/Drop)
For the trib port, The SMCG Pool have a relation with multiple port NEP (MC Pool)
The issue is when do we create the SMCG. It could represent all the add/drop port available in a ROADM node (around in the industry)
This use the concept of the aggregated port presented in the backup slide, with that, one could see the available resource of a group of port tied to a combiner or all the port of a CD (WSS SRG)
Also, NEP at the OMS should also carry information of the SRG that they belong

39. TAPI Topology and Connectivity

40. Graphical representation of Connection End Points
CEP connects-to-peer CEP via Encapsulated XC
(same layer) – terminate-and-map (a) or fixed-mapping (b) cases
Graphical simplifications F F =
CTP and TTP
(a)  F =
TTP =
CTP
(b)  = F F F
CTP and CTP

41. Disaggregation (Optical ROADM Only)

42. Disaggregation (Optical ROADM and ILA Only)

43. Tapi Model OMS-C (C-Band) OTC-C (C-Band) SMCA Connection
CEP
CEP
CEP
Passband [lowerfreq,upperfreq]
CTP_pac n
OMS-C MC Link (in GHz)
Pool_pac
NEP 1
Adapt_pac F
CEP
OMS-C (C-Band)
Term_pac
Passband [lowerfreq,upperfreq]
CTP_pac 1
OTS-C MC Link (in GHz)
Pool_pac
NEP 1
Adapt_pac F
CEP
OTC-C (C-Band)
Term_pac
Passband [lowerfreq,upperfreq]
CTP_pac n
OTS MC Link (in GHz)
NEP 1 F
CEP
MIP
Down MEP
Up MEP
CTP_pac
Media Pool
Pool_pac
NEP

44. Reference for TAPI OAM Overhead Layer (Most of it is from G.798)

45. Overhead Layer Overview

46. Overhead Layer Overview
The OTSiG-O may not be supported as presented here
The OTSiG-O may not have the TTP on a Transponder
For the OLS, the OTSiG-O may still be supported on the CTP

47. Overhead Layer Overview

48. Generic Layer Processing
From T-REC-G Generic layer fault processing Layer fault processing is concerned with the detection of failures within a layer network, the generation of consequent actions (for suppression of unwanted downstream alarms and remote information for upstream single-ended maintenance), and the report of probable fault causes to the management system. Figure 8-4 illustrates in general the atomic functions connection, trail termination and adaptation of a layer which perform their specific fault-processing tasks. The connection function, if present, can interconnect the adaptation and trail termination functions according to the signal flow shown. Note that not all features are supported by all layers. For the specific fault processing, see the layer‑specific functions.
Figure 8-4 – Generic layer fault processing

49. OSC Layer Function

50. OTS-O Layer Function

51. OTS-O Layer Function

52. OTS-O Layer Function (G.798 12/2017)

53. OMS-O Layer Function

54. OMS-O Layer Function

55. OMS-O Layer Function

56. OMS-O Layer Function

57. OTSiG-O Layer Function

58. Mapping from ITU-T and TMF Termination to ONF

59. Power Monitoring

60. OPM in ITU
Optical Power Measurement is define in ITU to monitor the total power associated to media channel, its mean that it is bound to select spectrum

61. OPM Location
Most of the implementation translate the location of the measurement point to a location at the demarcation point close to the pin (port)
This provides the best performance for EDFA gain and relate to the specification of the equipment
OpenROADM and Facebook TIP use that location for OPM

62. OPM in ITU
The T17-SG15-C-0521!R1!MSW-E contribution provide a example of OPM for an optical amplifier

63. Base Model
Need to monitor the power for each of the media channel

64. Model 1
Could be represented using tap coupler and pin monitor in the FC chain
The implementation normally assume that the pin monitor is compensated to the demarcation point but this could not be obvious to deduct
In this implementation, it is not exactly the right spectrum that is monitored

65. Model 2
In this implementation, the OPM reflect the power associated to the spectrum. It is the optical power seen in the media channel
Again, translation is required to present the information at the demarcation point

66. Proposal to define FC to represent PD Sensor
PD Sensors FC contain filtered Pin Monitor
The FC expose no loss from the input to the output with translation (Other FC will be included to represent effective lost where it should be present in the schema)
It contain list of OPM with spectrum definition
They could be place in the FC chain where we want to see the measurement
FC port of other FC can delegate their measurement to that PD Sensor

67. PD Sensor
The FC port were the media channel start delegate the measurement to the PD Sensor FC
The sensor is located to the wanted point of measurement
It present a Band Power measurement

68. Flex Channel Monitor Sensor
Possible Location for Channel Monitor
Only requirement from ITU is to detect if an NMC is present to feed the OTSiA OAM
For Control, it will be preferable to report SMC and NMC at the Demarcation point

69. Band Monitor (SMC and NMC)
The NMC power need to be consistent with their client server relation.
It could be translated to the demarcation point
Reported Power is spectrum bounded

70. OPM Monitor location

71. OPM
The TAPI stack expose CTP and TTP, those CEP present OPM package and the location could be referred into the Optical FC Schema (OpenDevice Schema in Facebook TIP)
The OPM stack maintain the OPM validity because of the client-server relationship

72. Backup

73. OTSiA connections FD of the ROADM node and FD of the Degrees
Add/Drop and Express
Use this model or use a model where OTSiA are supported by SMCG
Optical node will do SMCG connection

74. Base Model (Reduce view of Service MC)
Reduced View of the optical service media channel
CEP of the NMC could be added and remove
The FC does not require to be present to support signal detection (Only the CEP of the NMC and SMC)

75. Aggregated and Disaggregated view (WSS) Direction 1
Combiner and Splitter force the use of Access port that Aggregate Access Port
Service Media Channel Layer
Aggregated view:
ROADM node
From Trib to Line
Disaggregated view
Degree
SRG

76. Aggregated and Disaggregated view (WSS) Direction 2
Combiner and Splitter force the use of Access port that Aggregate Access Port
Service Media Channel Layer

77. Degree to Degree (WSS to WSS)
Aggregated view
Service media channel at the ROADM node
Disaggregated view
Service media channel at the Degree node
Service media chanel at the SRG (Add/Drop Share Risk Group)

78. Aggregated and Disaggregated view (WSS-WSS) Direction 1
Aggregated view from client to line interface
One FC for the service media channel
Disaggregated view from Client to System and System to Line
One FC for the service media channel for the Degree
One FC for the service media channel for the SRG (Add/Drop Share Risk Group)

79. Aggregated and Disaggregated view (WSS-WSS) Direction 2

80. Aggregated and disaggregated view (Filter) Direction 1
Filter architecture
Like a 200GHz AWG

81. Aggregated and disaggregated view (Filter) Direction 2

82. FC contain FC with different LPN
From a FC perspective, an FC could contain FCs. Since it is a passband defined by a filter (static), we could add FC that define passband associated to service media channel (inner media channel)
Service MC is a client of Band FC defined by the fixe filter

83. Aggregated and disaggregated view (Filter) Direction 1 Alternate View
Separate the Service MC Pool to follow the filter definition
Add the FC at the service media Channel
Could not contain FC Spec that define attenuation because the Filter FC define the attenuation

84. Aggregated and disaggregated view (Filter) Direction 2 Alternate View
Separate the Service MC Pool to follow the filter definition

85. OMS and OTS with FC
Expansion Of OMS and OTS

87. Layer model