TAPI Photonic Media Model Stephane St-Laurent, Infinera September 8, 2019 Updated 004

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

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

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)

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

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 defined in the context of a media channel It is used 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

OTSi An OTSi is an optical 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 center frequency

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

Multiple OTSiMC in an MC When multiple OTSiMC could be contained 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

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 agreed on. The non-adjacent-OTSiMC-spectrum give a better understanding to evaluate non-linear impairment (NLI).

Center Frequency Constraint on OTSiMC The OTSiMC center-frequency constraint is associated to the center frequency adjustment-granularity The 2 examples on the left show case of granularity of 25 and 12.5 GHz It is all associated to the equation: 193.1 + n * adjustment-granularity Need to add center-frequency constraint in the connectivity-service

Lower and Upper Frequency Constraint on OTSiMC The OTSiMC edge-frequency constraint is associated to the lower and upper frequency adjustment-granularity The 2 examples on the left show case of granularity of 6.25 and 12.5 GHz It is all associated to the equation: 193.1 + n * adjustment-granularity Note: A monitoring-point on an OTSiMC CEP could be limited, by an implementation, in passband frequency at a granularity specified by the adjustment-constraint. Example: a channel-monitor with a resolution of 12.5 GHz increment on a 12.5 GHz grid Need to add edge-frequency constraint on OTSiMC

frequency-constraint specification The frequency-constraint of the photonic model is specified using: grid-type: [DWDM, CWDM,FLEX, GRIDLESS, UNSPECIFIED] adjustment-granularity: [G_100GHZ, G_50GHZ, G_25GHZ, G_12_5GHZ, G_6_25GHZ, G_3_125GHZ, UNCONSTRAINTED]

Min and Max bandwidth constraint of OTSiMC CEP A node should be able to expose the constraint associated to the minimum and maximum bandwidth of OTSiMC passband of a CEP It should be presented in MHz Proposal: minimum-OTSiMC passband (MHz) maximum-OTSiMC passband (MHz) Presented in MC NEP (since the OTSiMC is dynamically created) Or in the connectivity constraint of the node at the MC layer qualifier

Lower and Upper Frequency Constraint on MC The MC edge-frequency constraint is associated to the lower and upper frequency adjustment-granularity It is presented by the MC NEP frequency-constraint information using grid-type and adjustment-granularity The examples show case of granularity of 6.25 and 12.5 GHz It is all associated to the equation: 193.1 + n * adjustment-granularity

Min and Max bandwidth constraint of MC CEP A node should be able to expose the constraint associated to the minimum and maximum bandwidth of MC passband of the CEP It should be presented in MHz Proposal: minimum-MC passband (MHz) maximum-MC passband (MHz) Presented in MC NEP Or in the connectivity constraint of the node at the MC layer qualifier

Media Channel NEP Specification The Media Channel NEP specification contain a list that provides the supportable-spectrum and its associated MC CEP frequency-constraint. It also contains available-spectrum and occupied-spectrum Its passband is specified by tuple of lower-frequency and upper- frequency in MHz It expose the adjustment-granularity and grid-type (for MC CEP constraint) As example: a list of 2 entries, one for the C band and one for the L band using flex-grid and an adjustment-granularity of 12.5 GHz

Allocation of MC CEP in MC NEP Assume no stacking for MC

Transponder Use Case

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 In the case of multiple interface to the ROADM node, the interfaces could be share

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 contain multiple OTSi In the case of multiple interface to the ROADM node, the interfaces could be share

OTSiA Assuming on OLS system (disaggregated) PCE that allocate the spectrum In the case of multiple OTSi that form a group, it is possible that: All the OTSi require the same spectrum bandwidth Or, the spectrum bandwidth is not be symmetric, example: 225 GHz on OTSi #1 and 200 GHz on OTSi #2 In this case, it may be required to know the bandwidth requirement per interface when doing a connectivity service

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

ROADM Client Interface (Interface associated to the OTSi)

ROADM Interface Client interface in a ROADM node could be shared For CD architecture, it is common to have interface that are connected internally using a combiner ( 4, 8, 12 ports as example) Those interface NEP should share the same group id It is similar for CDC architecture; it is possible for the connection that go to the same direction to share the spectrum through a optical combiner Those interface NEP should share the same group id

TAPI Media Model

Defining a network In its basis configuration, a disaggregated OLS Network could be expressed by a topology that contain node with MC NEP and Link between those NEP L12 A, B and C are ROADM node Only MC layer qualifier is required Link could be unidirectional A 01 02 B L21 10 L34 11 03 04 07 L43 05 L78 L87 L65 L56 08 C 06 topology = n1 12 topology-context

MC Network Media Channel CEP {lowerFreq, upperFreq} Media Channel Assembly [{lowerFreq, upperFreq}, {lowerFreq, upperFreq}, ..] Service Interface Point Node Edge Point Connection End Point (TTP + CTP) Connection End Point (CTP only) Connection End Point (Inverse mux CTP only) Connection End Point (TTP only) Node Edge Point Group MIP Down MEP Up MEP OPM Connection Exposing this topology is enough to request service (intent) or even to figure out service request in a declarative manner A B X1 X3 MC MC MC MC Link MC MC MC X2 X4 MC Link MC Link Need to know the connectivity between NEPs Non Intrusive Monitoring No Specific OAM signaling Optical Power Monitoring C MC X5