CCAMP Working Group Y. Lee
Internet-Draft SKKU (Sung Kyun Kwan University)
Intended status: Standards Track JL. Auge
Expires: August 26, 2021 Orange
V. Lopez
Telefonica
G. Galimberti
Cisco
D. Beller
Nokia
February 22, 2021
A YANG Data Model for Optical Impairment-aware Topology
draft-ietf-ccamp-optical-impairment-topology-yang-06
Abstract
In order to provision an optical connection through optical networks,
a combination of path continuity, resource availability, and
impairment constraints must be met to determine viable and optimal
paths through the network. The determination of appropriate paths is
known as Impairment-Aware Routing and Wavelength Assignment (IA-RWA)
for WSON, while it is known as Impairment-Aware Routing and Spectrum
Assigment (IA-RSA) for SSON.
This document provides a YANG data model for the impairment-aware TE
topology in optical networks.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on August 26, 2021.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
1.2. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 4
1.3. Prefixes in Data Node Names . . . . . . . . . . . . . . . 4
2. Reference Architecture . . . . . . . . . . . . . . . . . . . 5
2.1. Control Plane Architecture . . . . . . . . . . . . . . . 5
2.2. Transport Data Plane . . . . . . . . . . . . . . . . . . 6
2.3. OMS Media Links . . . . . . . . . . . . . . . . . . . . . 7
2.3.1. Optical Tributary Signal (OTSi) . . . . . . . . . . . 8
2.3.2. Optical Tributary Signal Group (OTSiG) . . . . . . . 8
2.3.3. Media Channel (MC) . . . . . . . . . . . . . . . . . 9
2.3.4. Media Channel Group (MCG) . . . . . . . . . . . . . . 10
2.4. Amplifiers . . . . . . . . . . . . . . . . . . . . . . . 11
2.5. Transponders . . . . . . . . . . . . . . . . . . . . . . 12
2.5.1. Standard Modes . . . . . . . . . . . . . . . . . . . 12
2.5.2. Organizational Modes . . . . . . . . . . . . . . . . 13
2.5.3. Explicit Modes . . . . . . . . . . . . . . . . . . . 14
2.5.4. Transponder Capabilities and Current Configuration . 15
2.6. WSS/Filter . . . . . . . . . . . . . . . . . . . . . . . 16
2.7. Optical Fiber . . . . . . . . . . . . . . . . . . . . . . 16
2.8. ROADM Node Architectures . . . . . . . . . . . . . . . . 16
2.8.1. Integrated ROADM Architecture with Integrated Optical
Transponders . . . . . . . . . . . . . . . . . . . . 17
2.8.2. Integrated ROADMs with Integrated Optical
Transponders and Single Channel Add/Drop Interfaces
for Remote Optical Transponders . . . . . . . . . . . 18
2.8.3. Disaggregated ROADMs Subdivided into Degree,
Add/Drop, and Optical Transponder Subsystems . . . . 19
2.8.4. Optical Impairments Imposed by ROADM Nodes . . . . . 20
3. YANG Model (Tree Structure) . . . . . . . . . . . . . . . . . 22
4. Optical Impairment Topology YANG Model . . . . . . . . . . . 27
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5. Security Considerations . . . . . . . . . . . . . . . . . . . 56
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 56
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 57
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 57
8.1. Normative References . . . . . . . . . . . . . . . . . . 57
8.2. Informative References . . . . . . . . . . . . . . . . . 57
Appendix A. Contributors . . . . . . . . . . . . . . . . . . . . 59
Appendix B. Additional Authors . . . . . . . . . . . . . . . . . 59
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 61
1. Introduction
In order to provision an optical connection (an optical path) through
a wavelength switched optical networks (WSONs) or spectrum switched
optical networks (SSONs), a combination of path continuity, resource
availability, and impairment constraints must be met to determine
viable and optimal paths through the network. The determination of
appropriate paths is known as Impairment-Aware Routing and Wavelength
Assignment (IA-RWA) [RFC6566] for WSON, while it is known as IA-
Routing and Spectrum Assigment (IA-RSA) for SSON.
This document provides a YANG data model for the impairment-aware
Traffic Engineering (TE) topology in WSONs and SSONs. The YANG model
described in this document is a WSON/SSON technology-specific Yang
model based on the information model developed in [RFC7446] and the
two encoding documents [RFC7581] and [RFC7579] that developed
protocol independent encodings based on [RFC7446].
The intent of this document is to provide a YANG data model, which
can be utilized by a Multi-Domain Service Coordinator (MDSC) to
collect states of WSON impairment data from the Transport PNCs to
enable impairment-aware optical path computation according to the
ACTN Architecture [RFC8453]. The communication between controllers
is done via a NETCONF [RFC8341] or a RESTCONF [RFC8040].
Similarly,this model can also be exported by the MDSC to a Customer
Network Controller (CNC), which can run an offline planning process
to map latter the services in the network.
It is worth noting that optical data plane interoperability is a
complex topic especially in a multi vendor environment and usually
requires joint engineering, which is independent from control plane
and management plane capabilities. The YANG data model defined in
this draft is providing sufficient information to enable optical
impairment aware path computation.
Optical data plane interoperability is outside the scope of this
draft.
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This document augments the generic TE topology draft [RFC8795] where
possible.
This document defines one YANG module: ietf-optical-impairment-
topology (Section 3) according to the new Network Management
Datastore Architecture [RFC8342].
1.1. Terminology
Refer to [RFC6566], [RFC7698], and [G.807] for the key terms used in
this document.
The following terms are defined in [RFC7950] and are not redefined
here:
o client
o server
o augment
o data model
o data node
The following terms are defined in [RFC6241] and are not redefined
here:
o configuration data
o state data
The terminology for describing YANG data models is found in
[RFC7950].
1.2. Tree Diagram
A simplified graphical representation of the data model is used in
Section 2 of this this document. The meaning of the symbols in these
diagrams is defined in [RFC8340].
1.3. Prefixes in Data Node Names
In this document, names of data nodes and other data model objects
are prefixed using the standard prefix associated with the
corresponding YANG imported modules, as shown in Table 1.
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+--------------+--------------------------+-------------------------+
| Prefix | YANG module | Reference |
+--------------+--------------------------+-------------------------+
| optical-imp- | ietf-optical-impairment- | [RFCXXXX] |
| topo | topology | |
| layer0-types | ietf-layer0-types | [I-D.ietf-ccamp-layer0- |
| | | types] |
| nw | ietf-network | [RFC8345] |
| nt | ietf-network-topology | [RFC8345] |
| tet | ietf-te-topology | [RFC8795] |
+--------------+--------------------------+-------------------------+
Table 1: Prefixes and corresponding YANG modules
[Editor's note: The RFC Editor will replace XXXX with the number
assigned to the RFC once this draft becomes an RFC.]
2. Reference Architecture
2.1. Control Plane Architecture
Figure 1 shows the control plane architecture.
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+--------+
| MDSC |
+--------+
Scope of this ID -------> ||
| ||
| +------------------------+
| | OPTICAL |
+---------+ | | DOMAIN | +---------+
| Device | | | CONTROLLER | | Device |
| config. | | +------------------------+ | config. |
+---------+ v // || \\ +---------+
______|______ // || \\ ______|______
/ OT \ // || \\ / OT \
| +--------+ |// __--__ \\| +--------+ |
| |Vend. A |--|----+ ( ) +----|--| Vend. A| |
| +--------+ | | ~-( )-~ | | +--------+ |
| +--------+ | +---/ \---+ | +--------+ |
| |Vend. B |--|--+ / \ +--|--| Vend. B| |
| +--------+ | +---( OLS Segment )---+ | +--------+ |
| +--------+ | +---( )---+ | +--------+ |
| |Vend. C |--|--+ \ / +--|--| Vend. C| |
| +--------+ | +---\ /---+ | +--------+ |
| +--------+ | | ~-( )-~ | | +--------+ |
| |Vend. D |--|----+ (__ __) +----|--| Vend. D| |
| +--------+ | -- | +--------+ |
\_____________/ \_____________/
^ ^
| |
| |
Scope of [I-D.ietf-ccamp-dwdm-if-param-yang]
Figure 1: Scope of draft-ietf-ccamp-dwdm-if-param-yang
The models developed in this document is an abstracted YANG model
that may be used in the interfaces between the MDSC and the Optical
Domain Controller (aka MPI) and between the Optical Domain Controller
and the Optical Device (aka SBI) in Figure 1. It is not intended to
support a detailed low-level DWDM interface model. DWDM interface
model is supported by the models presented in
[I-D.ietf-ccamp-dwdm-if-param-yang].
2.2. Transport Data Plane
This section provides the description of the reference optical
network architecture and its relevant components to support optical
impairment-aware path computation.
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Figure 2 shows the reference architecture.
+-------------------+ +-------------------+
| ROADM Node | | ROADM Node |
| | | |
| PA +-------+ BA | ILA | PA +-------+ BA |
| +-+ | WSS/ | +-+ | _____ +--+ _____ | +-+ | WSS/ | +-+ |
--|-| |-|Filter |-| |-|-()____)-| |-()____)-|-| |-|Filter |-| |-|--
| +-+ | | +-+ | +--+ | +-+ | | +-+ |
| +-------+ | optical | +-------+ |
| | | | | fiber | | | | |
| o o o | | o o o |
| transponders | | transponders |
+-------------------+ +-------------------+
OTS Link OTS Link
<---------> <--------->
OMS Link
<-------------------------------->
PA: Pre-Amplifieror
BA: Booster Amplifier
ILA: In-Line Amplifier
Figure 2: Reference Architecture for Optical Transport Network
BA (on the left side ROADM) is the ingress Amplifier and PA (on the
right side ROADM is the egress amplifier for the OMS link shown in
Figure 2.
2.3. OMS Media Links
According to [G.872], OMS Media Link represents a media link between
two ROADMs. Specifically, it originates at the ROADM's Filter in the
source ROADM and terminates at the ROADM's Filter in the destination
ROADM.
OTS Media Link represents a media link:
(i) between ROADM's BA and ILA;
(ii) between a pair of ILAs;
(iii) between ILA and ROADM's PA.
OMS Media link can be decomposed in a sequence of OTS links type (i),
(ii), and (iii) as discussed above. OMS Media link would give an
abstracted view of impairment data (e.g., power, OSNR, etc.) to the
network controller.
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For the sake of optical impairment evaluation OMS Media link can be
also decomposed in a sequence of elements such as BA, fiber section,
ILA, concentrated loss and PA.
[Editor's note: text below related to [G.807] needs to be revised!
[G.807] is now in publication process.]
2.3.1. Optical Tributary Signal (OTSi)
The OTSi is defined in ITU-T Recommendation G.959.1, section 3.2.4
[G.959.1]. The YANG model defined below assumes that a single OTSi
consists of a single modulated optical carrier. This single
modulated optical carrier conveys digital information.
Characteristics of the OTSi signal are modulation scheme (e.g. QPSK,
8-QAM, 16-QAM, etc.), baud rate (measure of the symbol rate), pulse
shaping (e.g. raised cosine - complying with the Nyquist inter symbol
interference criterion), etc.
2.3.2. Optical Tributary Signal Group (OTSiG)
The definition of the OTSiG is currently being moved from ITU-T
Recommendation G.709 [G.709] to the new draft Recommendation G.807
(still work in progress) [G.807]. The OTSiG is an electrical signal
that is carried by one or more OTSi's. The relationship between the
OTSiG and the the OTSi's is described in ITU-T draft Recommendation
G.807, section 10.2 [G.807]. The YANG model below supports both
cases: the single OTSi case where the OTSiG contains a single OTSi
(see ITU-T draft Recommendation G.807, Figure 10-2) and the multiple
OTSi case where the OTSiG consists of more than one OTSi (see ITU-T
draft Recommendation G.807, Figure 10-3). From a layer 0 topology
YANG model perspective, the OTSiG is a logical construct that
associates the OTSi's, which belong to the same OTSiG. The typical
application of an OTSiG consisting of more than one OTSi is inverse
multiplexing. Constraints exist for the OTSi's belonging to the same
OTSiG such as: (i) all OTSi's must be co-routed over the same optical
fibers and nodes and (ii) the differential delay between the
different OTSi's may not exceed a certain limit. Example: a 400Gbps
client signal may be carried by 4 OTSi's where each OTSi carries
100Gbps of client traffic.
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OTSiG
_________________________/\__________________________
/ \
m=7
- - - +---------------------------X---------------------------+ - - -
/ / / | | / / /
/ / /| OTSi OTSi OTSi OTSi |/ / /
/ / / | ^ ^ ^ ^ | / / /
/ / /| | | | | |/ / /
/ / / | | | | | | / / /
/ / /| | | | | |/ / /
-4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12
--+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---
n = 4
K1 K2 K3 K4
Figure 3: MC Example containing all 4 OTSi signals of an OTSiG
2.3.3. Media Channel (MC)
The definition of the MC is currently being moved from ITU-T
Recommendation G.872 [G.872] to the new draft Recommendation G.807
(still work in progress) [G.807]. Section 3.2.2 defines the term MC
and section 7.1.2 provides a more detailed description with some
examples. The definition of the MC is very generic (see ITU-T draft
Recommendation G.807, Figure 7-1). In the YANG model below, the MC
is used with the following semantics:
The MC is an end-to-end topological network construct and can be
considered as an "optical pipe" with a well-defined frequency slot
between one or more optical transmitters each generating an OTSi and
the corresponding optical receivers terminating the OTSi's. If the
MC carries more than one OTSi, it is assumed that these OTSi's belong
to the same OTSiG.
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m=8
+-------------------------------X-------------------------------+
| | |
| +----------X----------+ | +----------X----------+ |
| | OTSi | | OTSi | |
| | ^ | | | ^ | |
| | | | | | | |
-4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12
--+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+-
| n=4 |
K1 K2
<------------------------ Media Channel ----------------------->
Figure 4: Figure Caption TBA
The frequency slot of the MC is defined by the n value defining the
central frequency of the MC and the m value that defines the width of
the MC following the flexible grid definition in ITU-T Recommendation
G.694.1 [G.694.1]. In this model, the effective frequency slot as
defined in ITU-T draft Recommendation G.807 is equal to the frequency
slot of this end-to-end MC. It is also assumed that ROADM devices
can switch MCs. For various reasons (e.g. differential delay), it
is preferred to use a single MC for all OTSi's of the same OTSiG. It
may however not always be possible to find a single MC for carrying
all OTSi's of an OTSiG due to spectrum occupation along the OTSiG
path.
2.3.4. Media Channel Group (MCG)
The definition of the MCG is currently work in progress in ITU-T and
is defined in section 7.1.3 of the new ITU-T draft Recommendation
G.807 (still work in progress) [G.807]. The YANG model below assumes
that the MCG is a logical grouping of one or more MCs that are used
to to carry all OTSi's belonging to the same OTSiG.
The MCG can be considered as an association of MCs without defining a
hierarchy where each MC is defined by its (n,m) value pair. An MCG
consists of more than one MC when no single MC can be found from
source to destination that is wide enough to accommodate all OTSi's
(modulated carriers) that belong to the same OTSiG. In such a case
the set of OTSi's belonging to a single OTSiG have to be split across
2 or more MCs.
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MCG1 = {M1.1, M1.2}
__________________________/\________________________
/ \
M1.1 M2 M1.2
____________/\____________ _____/\_____ ____/\____
/ \/ \/ \
- - - +---------------------------+-------------+-----------+ - - -
/ / / | | / / / / / / | | / / /
/ / /| OTSi OTSi OTSi |/ / / / / / /| OTSi |/ / /
/ / / | ^ ^ ^ | / / / / / / | ^ | / / /
/ / /| | | | |/ / / / / / /| | |/ / /
/ / / | | | | | / / / / / / | | | / / /
/ / /| | | | |/ / / / / / /| | |/ / /
-7 -4 -1 0 1 2 3 4 5 6 7 8 ... 14 17 20
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
n=0 n=17
K1 K2 K3 K4
Figure 5: Figure Caption TBA
The MCG is relevant for path computation because all end-to-end MCs
belonging to the same MCG have to be co-routed, i.e., have to follow
the same path. Additional constraints may exist (e.g. differential
delay).
2.4. Amplifiers
Optical amplifiers are in charge of amplifying the optical signal in
the optical itself without any electrical conversion. There are
three main technologies to build amplifiers: Erbium Doped Fiber
Amplifier (EDFA), Raman Fiber Amplifier (RFA), and Semiconductor
Optical Amplifier (SOA). Nowadays, most of optical networks uses
EDFAs. However, RFA has an attractive feature that it works in any
wavelength band with a similar or lower noise figures compared to
EDFA. On the other hand, RFAs consumes more power and are more
expensive than EDFAs.
Amplifiers can be classified according to their location in the
communication link. There are three basic types of amplifiers: ILA,
Pre-Amplifier and Booster. ILA is In-Line Amplifier which is a
separate node type while Pre-Amplifier and Booster Amplifier are
integral elements of ROADM node. From a data modeling perspective,
Pre-Amplifier and Booster Amplifier are internal functions of a ROADM
node and as such these elements are hidden within ROADM node. In
this document, we would avoid internal node details, but attempt to
abstract as much as possible.
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One modeling consideration of the ROADM internal is to model power
parameter through the ROADM, factoring the output power from the Pre-
Amplifier minus the ROADM power loss would give the input power to
the Booster Amplifier. In other words, Power_in (@ ROADM Booster) =
Power_out (@ ROADM Pre-Amplifier) - Power_loss (@ ROADM WSS/Filter).
2.5. Transponders
[Editor's note: The relationship between the transponder and the OTSi
in the YANG model described in Section 3 needs further clarification
and refinement.]
A Transponder is the element that sends and receives the optical
signal from a DWDM network. A transponder can comprise one or more
transceivers. A transceiver can be seen as a pair of transmitter and
receiver, as defined in ITU-T Recommendation G.698.2 [G.698.2].
A transponder is typically characterized by its data/symbol rate and
the maximum distance the signal can travel. Other transponder
properties are: carrier frequency for the optical channels, output
power per channel, measured input power, modulation scheme, FEC, etc.
From a path computation perspective, the selection of the compatible
configuration of the source and the destination transceivers is an
important factor for optical signals to traverse through the DWDM
network.
The YANG model defines three different approaches to describe the
transceiver capabilities (called "modes") that are needed to
determine optical signal compatibility:
o Standard Modes
o Organizational Modes
o Explicit Modes
2.5.1. Standard Modes
A standard mode is related to an optical specification developed by
an SDO organization. Currently, the "Standard Modes" can only be
referred to ITU-T G.698.2 [G.698.2] since G.698.2 is the only
specification defining "Standard Modes" today. Nothing is
precluding, however, to consider other specifications provided by any
other SDO in the Standard Mode context as soon as such sepcifications
will be available. An application code as defined in ITU-T G.698.2
[G.698.2] is representing a standard ITU-T G.698.2 optical interface
specification towards the realization of transversely compatible DWDM
systems. Two transceivers supporting the same application code and a
line system matching the constraints, defined in ITU-T G.698.2, for
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that application code will interoperate. As the characteristics are
encoded in the application code, the YANG model in this document only
defines a string, which represents that application code.
2.5.2. Organizational Modes
Organizations like operator groups, industry fora, or equipment
vendors can define their own optical interface specifications and
make use of transceiver capabilities going beyond existing standards.
An organizational mode is identified by the organization-identifier
attribute defining the scope and an operational-mode that is
meaningful within the scope of the organization. Hence, the two
attributes must always be considered together. It is the
responsibility of the organization to assign operational modes and to
ensure that operational modes are unique and unambiguous within the
scope of the organization.
Two transceivers can be interconnected, if they have at least one
(organization-identifier, operational-mode) pair in common and if the
supported carrier frequency and power attributes have a matching
range. This is a necessary condition for path computation in the
context of organizational modes.
An operational mode is a transceiver preset (a configuration with
well-defined parameter values) subsuming several transceiver
properties defined by the optical interface specification - these
properties are not provided for anoperational mode and are therefore
not defined in the YANG model. Examples of these properties are:
o FEC type
o Modulation scheme
o Encoding (mapping of bit patterns (code words) to symbols in the
constellation diagram)
o Baud rate (symbol rate)
o Carrier bandwidth (typically measured in GHz)
The major reason for these transceiver presets is the fact that the
attribute values typically cannot be configured independently and are
therefore advertised as supported operational mode capabilities. It
is the responsibility of the organization to assign operational modes
and to ensure that operational modes are unique and not ambiguous
within the scope of the organization.
In addition to the transceiver properties subsumed by the operational
mode, optical power and carrier frequency related properties are
modeled separately, i.e., outside of the operational mode. This
modeling approach allows transponders using different transceiver
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variants (e.g. optical modules) with slightly different power and/or
frequency range properties to interoperate without defining separate
operational modes. Different optical modules (pluggables) from
different suppliers typically have slightly different input and
output power ranges or may have slightly different carrier frequency
tuning ranges.
The received channel power and the received total power are two
parameters that can be measured by the receiver and can be provided
by the transceiver in order to allow a controller to determine the
expected performance of the end-to-end service taking into account
the optical impairments along the path.
An organization may define the operational modes to include the
optical power and carrier frequency related properties following the
application code approach as defined in ITU-T Recommendation G.698.2
[G.698.2]. In such a case, the explicit optical power and carrier
frequency related optional attributes shall be omitted in order to
avoid redundant information in the description of the transceiver
capabilities. If these attributes are provided in addition to the
operational modes including these attribute values implicitly, the
parameter values provided explicitly replace the implicit values and
take precedence. This shall, however, only be an done in exceptional
cases and shall be avoided whenever possible. In case an implicitly
given range is extended utilizing the explicit optional attributes, a
path computation policy rule may be applied to select a value
preferably from the range defined implicitly and to only select a
value from the extended range if no path can be found for values in
the implicitly defined range. Path computation policy is outside the
scope of this topology YANG model.
In summary, the optical power and carrier frequency related
attributes shall either be described implicitly by the operational
mode following the definition provided by that organization or shall
be described explicitly when the optical power and carrier frequency
related properties are not included in the operational mode
definition.
2.5.3. Explicit Modes
The explicit mode allows to encode, explicitly, any subset of
parameters e.g., FEC type, Modulation type, etc, to enable a
controller entity to check for interoperability by means outside of
this draft. It shall be noted that using the explicit encoding does
not guarantee interoperability between two transceivers even in case
of identical parameter definitions. The explicit mode shall
therefore be used with care, but it could be useful when no common
Application Codes or Organizational Modes exist or the constraints of
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common Application Codes or Organizational Modes cannot be met by the
line system.
2.5.4. Transponder Capabilities and Current Configuration
The YANG model described in Section 3 defines the optical transceiver
properties. They are divided between:
a. Optical transceiver capabilities, describing how it can be
configured
b. Current transceiver setting, indicating how it is currently
configured
The transceiver capabilities are described by the set of modes the
transceiver is supporting. Each mode MUST follow only one of the
three mode options defined above (choice in the YANG model). The
YANG model allows to describe the transceiver capabilities by mixing
different modes. A transceiver may support some ITU-T application
codes and in addition some organizational or explicit modes.
A transceiver mode description comprises the following properties:
o Supported transmitter tuning range with min/max nominal carrier
frequency [f_tx_min, f_tx_max]
o Supported transmitter tunability grid, the distance between two
adjacent carrier frequencies (in GHz)
o Supported transmitter power range [p_tx-min, p_tx_max]
o Supported receiver channel power range [p_rx-min, p_rx_max]
o Supported maximum total power, rx power for all channels fed into
the receiver
These optical transceiver properties are explicitly defined in the
model for explicit and organizational modes, while they are
implicitly defined for the application codes (see ITU-T G698.2
[G.698.2]).
The set of optical impairment limits, e.g., min OSNR, max PMD, max
CD, max PDL, Q-factor limit, are explicitly defined for the explicit
modes while they are defined implicitly for the application codes and
organizational modes.
It is possible that the set of parameter values defined for an
explicit mode may also be represented in form of an organizational
mode or one or more application codes. The "supported-mode"
container may provide two different lists with pointers to
application codes and organizational modes, respectively.
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The current transponder configuration describes the properties of the
OTSi transmitted or received by the transceiver attached to a
specific transponder port.
Each OTSi has the following three pointer attributes modeled as
leafrefs:
o Pointer to the transponder instance containing the transceiver
terminating the OTSi
o Pointer to the transceiver instance terminating the OTSi
o Pointer to the currently configured transceiver mode
Additionally, the OTSi is described by the following frequency and
optical power related attributes:
o current carrier-frequency
o currently transmitted channel power
o currently received channel power
o currently received total power
2.6. WSS/Filter
WSS separates the incoming light input spectrally as well as
spatially, then chooses the wavelength that is of interest by
deflecting it from the original optical path and then couple it to
another optical fibre port. WSS/Filter is internal to ROADM. So
this document does not model the inside of ROADM.
2.7. Optical Fiber
There are various optical fiber types defined by ITU-T. There are
several fiber-level parameters that need to be factored in, such as,
fiber-type, length, loss coefficient, pmd, connectors (in/out).
ITU-T G.652 defines Standard Singlemode Fiber; G.654 Cutoff Shifted
Fiber; G.655 Non-Zero Dispersion Shifted Fiber; G.656 Non-Zero
Dispersion for Wideband Optical Transport; G.657 Bend-Insensitive
Fiber. There may be other fiber-types that need to be considered.
2.8. ROADM Node Architectures
The ROADM node architectures in today's dense wavelength division
multiplexing (DWDM) networks can be categorized as follows:
o Integrated ROADM architecture with integrated optical transponders
o Integrated ROADM architecture with integrated optical transponders
and single channel add/drop ports for remote optical transponders
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o Disaggregated ROADM architecture where the ROADM is subdivided
into degree, add/drop, and optical transponder subsystems handled
as separate network elements
The TE topology YANG model augmentations including optical
impairments for DWDM networks defined below intend to cover all the 3
categories of ROADM architectures listed above. In the case of a
disaggregated ROADM architecture, it is assumed that optical domain
controller already performs some form of abstraction and presents the
TE-node representing the disaggregated ROADM in the same way as an
integrated ROADM with integrated optical transponders if the optical
transponder subsystems and the add/drop subsystems are collocated
(short fiber links not imposing significant optical impairments).
The different ROADM architectures are briefly described and
illustrated in the following subsections.
[Editor's note: The modeling of remote optical transponders located
for example in the client device with a single channel link between
the OT and the add/drop port of the ROADM requires further
investigations and will be addressed in a future revision of this
document.]
2.8.1. Integrated ROADM Architecture with Integrated Optical
Transponders
Figure 2 and Figure 6 below show the typical architecture of an
integrated ROADM node, which contains the optical transponders as an
integral part of the ROADM node. Such an integrated ROADM node
provides DWDM interfaces as external interfaces for interconnecting
the device with its neighboring ROADMs (see OTS link above). The
number of these interfaces denote also the degree of the ROADM. A
degree 3 ROADM for example has 3 DWDM links that interconnect the
ROADM node with 3 neighboring ROADMs. Additionally, the ROADM
provides client interfaces for interconnecting the ROADM with client
devices such as IP routers or Ethernet switches. These client
interfaces are the client interfaces of the integrated optical
transponders.
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. . . . . . . . . . . . . . . . . .
+-----.-------------------------------- .-----+
| . ROADM . |
| . /| +-----------------+ |\ . |
Line | . / |--| |--| \ . | Line
WEST | /| . | |--| |--| | . |\ | EAST
------+-/ |-.-| |--| OCX |--| |-.-| \-+-----
------+-\ |-.-| |--| |--| |-.-| /-+-----
| \| . | |--| |--| | . |/ |
| . \ |--| |--| / . |
| . \| +-----------------+ |/ . |
| . . |
| . +---+ +---+ +---+ +---+ . |
| . | O | | O | | O | | O | . |
| . | T | | T | | T | | T | . |
| . +---+ +---+ +---+ +---+ . |
| . | | | | | | | | . |
+-----.------+-+---+-+---+-+---+-+------.-----+
. . . .|.| . |.| . |.| . |.|. . . .
| | | | | | | | TE Node
Client Interfaces
Figure 6: ROADM Architectiure with Integrated Transponders
2.8.2. Integrated ROADMs with Integrated Optical Transponders and
Single Channel Add/Drop Interfaces for Remote Optical
Transponders
Figure 7 below shows the extreme case where all optical transponders
are not integral parts of the ROADM but are separate devices that are
interconnected with add/drop ports of the ROADM. If the optical
transponders and the ROADM are collocated and if short single channel
fiber links are used to interconnect the optical transponders with an
add/drop port of the ROADM, the optical domain controller may present
these optical transponders in the same way as integrated optical
transponders. If, however, the optical impairments of the single
channel fiber link between the optical transponder and the add/drop
port of the ROADM cannot be neglected, it is necessary to represent
the fiber link with its optical impairments in the topology model
This also implies that the optical transponders belong to a separate
TE node
[Editor's note: this requires further study].
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. . . . . . . . . . . . . . . . . .
. Abstracted ROADM .
+-----.-------------------------------- .-----+
| . ROADM . |
| . /| +-----------------+ |\ . |
Line | . / |--| |--| \ . | Line
WEST | /| . | |--| |--| | . |\ | EAST
------+-/ |-.-| |--| OCX |--| |-.-| \-+-----
------+-\ |-.-| |--| |--| |-.-| /-+-----
| \| . | |--| |--| | . |/ |
| . \ |--| |--| / . |
| . \| +-----------------+ |/ . |
+-----.---------|----|---|----|---------.-----|
Colored OT . +-+ ++ ++ +-+ .
line I/F . | | | | .
. +---+ +---+ +---+ +---+ .
. | O | | O | | O | | O | .
. | T | | T | | T | | T | .
. +---+ +---+ +---+ +---+ .
. . . .|.| . |.| . |.| . |.|. . . .
| | | | | | | | TE Node
Client Interfaces
Figure 7: ROADM Architectiure with Remote Transponders
2.8.3. Disaggregated ROADMs Subdivided into Degree, Add/Drop, and
Optical Transponder Subsystems
Recently, some DWDM network operators started demanding ROADM
subsystems from their vendors. An example is the OpenROADM project
where multiple operators and vendors are developing related YANG
models. The subsystems of a disaggregated ROADM are: single degree
subsystems, add/drop subsystems and optical transponder subsystems.
These subsystems separate network elements and each network element
provides a separate management and control interface. The subsystems
are typically interconnected using short fiber patch cables and form
together a disaggregated ROADM node. This disaggregated ROADM
architecture is depicted in Figure 8 below.
As this document defines TE topology YANG model augmentations
[RFC8795] for the TE topology YANG model provided at the north-bound
interface of the optical domain controller, it is a valid assumption
that the optical domain controller abstracts the subsystems of a
disaggregated ROADM and presents the disaggregated ROADM in the same
way as an integrated ROADM hiding all the interconnects that are not
relevant from an external TE topology view.
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. . . . . . . . . . . . . . . . . .
. Abstracted ROADM .
+-----.----------+ +----------.-----+
| Degree 1 | | Degree 2 |
Line | . +-----+ | + +-----+ . | Line
1 | /| . | W |-|------------|-| W | . |\ | 2
-----+-/ |-.--| S ******** ******** S |--.-| \-+-----
-----+-\ |-.--| S | | * * | | S |--.-| /-+-----
| \| . | |-|-+ * * +-|-| | . |/ |
| . +-+-+-+ | | * * | | +-+-+-+ . |
+-----.----|-----+ | * * | +-----|----.-----+
. | | * * | | .
+-----.----|-----+ | * * | +-----|----.-----+
| Degree 4 | | | * * | | | Degree 3 |
Line | . +-----+ | | * * | | +-----+ . | Line
4 | /| . | W |-|-|--*--*--+ | | W | . |\ | 3
-----+-/ |-.--| S | | +--*--*----|-| S |--.-| \-+-----
-----+-\ |-.--| S |-|----*--*----|-| S |--.-| /-+-----
| \| . | | | * * | | | . |/ |
| . +--*--+ | * * | +--*--+ . |
+-----.-----*----+ * * +----*-----.-----+
. * * * * .
. +--*---------*--*---------*--+ .
. | ADD | .
. | DROP | .
. +----------------------------+ .
Colored OT . | | | | .
Line I/F . +---+ +---+ +---+ +---+ .
. | O | | O | | O | | O | .
. | T | | T | | T | | T | .
. +---+ +---+ +---+ +---+ .
. . .|.| . |.| . |.| . |.|. . .
| | | | | | | | TE Node
Client Interfaces
Figure 8: Disaggregated ROADM Architecture with Remote Transponders
2.8.4. Optical Impairments Imposed by ROADM Nodes
When an optical OTSi signal traverses a ROADM node, optical
impairments are imposed on the signal by various passive or active
optical components inside the ROADM node. Examples of optical
impairments are:
o Chromatic dispersion (CD)
o Polarization mode dispersion (PMD)
o Polarization dependent loss (PDL)
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o Optical amplifier noise due to amplified spontaneous emission
(ASE)
o In-band cross-talk
o Filtering effects (for further study)
A ROADM node contains a wavelength selective photonic switching
function (WSS)that is capable of switching media channels (MCs)
described in Section 2.3.4. These MCs can be established between two
line ports of the ROADM or between a line port and an Add/Drop port
of the ROADM. The Add/Drop ports of a ROADM are those ports to which
optical transponders are connected. Typically, this is a single
channel signal (single OTSi), but principally this could also be a
group of OTSi signals. The optical impairments associated with these
MCs are different and the paths of the MCs inside the ROADM node can
be categorized as follows:
o Express path: MC path between two line ports of the ROADM
(unidirectional)
o Add Path: MC path from an Add port to a line port of the ROADM
o Drop path: MC path from a line port to a Drop port of the ROADM
Due to the symmetrical architecture of the ROADM node, the optical
impairments associated with the express path are typically the same
between any two line ports of the ROADM whereas the optical
impairments for the add and drop paths are different and therefore
have to be modeled separately.
The optical impairments associated with each of the three types of
ROADM-node-internal paths described above are modeled as optical
impairment parameter sets. These parameter sets are modeled as an
augmentation of the te-node-attributes defined in [RFC8795]. The te-
node-attributes are augmented with a list of roadm-path-impairments
for the three ROADM path types distinguished by the impairment-type.
Each roadm-path-impairments list entry contains the set of optical
impairment parameters for one of the three path types indicated by
the impairment-type. For the optical feasibility calculation based
on the optical impairments, it is necessary to know whether the
optical power of the OTSi stays within a certain power window. This
is reflected by some optical power related parameters such as loss
parameters or power parameters, which are included in the optical
impairment parameter sets (see tree view in Section 3).
[RFC8795] defines a connectivity matrix and a local link connectivity
list for the TE node. The connectivity matrix describes the
connectivity for the express paths between the different lines of the
ROADM and the local link connectivity list describes the connectivity
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for the Add and Drop paths of the ROADM. These matrices are
augmented with a new roadm-path-impairment matrix element, an add-
path-impairment, and drop-path-impairment matrix element,
respectively, which are defined as a pointer to the corresponding
entry in the roadm-path-impairments list (leaf-ref).
[Editor's note: this section is still work in progress]
3. YANG Model (Tree Structure)
module: ietf-optical-impairment-topology
augment /nw:networks/nw:network/nw:network-types/tet:te-topology:
+--rw optical-impairment-topology!
augment /nw:networks/nw:network/nt:link/tet:te
/tet:te-link-attributes:
+--ro OMS-attributes
+--ro generalized-snr? l0-types-ext:snr
+--ro equalization-mode identityref
+--ro (power-param)?
| +--:(channel-power)
| | +--ro nominal-channel-power? decimal64
| +--:(power-spectral-density)
| +--ro nominal-power-spectral-density? decimal64
+--ro media-channel-group* [i]
| +--ro i int16
| +--ro media-channels* [flexi-n]
| +--ro flexi-n l0-types:flexi-n
| +--ro flexi-m? l0-types:flexi-m
| +--ro OTSiG-ref? leafref
| +--ro OTSi-ref? leafref
+--ro OMS-elements* [elt-index]
+--ro elt-index uint16
+--ro oms-element-uid? string
+--ro (element)
+--:(amplifier)
| +--ro amplifier
| +--ro type-variety string
| +--ro operational
| +--ro amplifier-element* []
| +--ro name?
| | string
| +--ro frequency-range
| | +--ro lower-frequency?
| | | l0-types-ext:frequency-thz
| | +--ro upper-frequency?
| | l0-types-ext:frequency-thz
| +--ro actual-gain
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| | decimal64
| +--ro tilt-target
| | decimal64
| +--ro out-voa
| | decimal64
| +--ro in-voa
| | decimal64
| +--ro (power-param)?
| +--:(channel-power)
| | +--ro nominal-channel-power?
| | decimal64
| +--:(power-spectral-density)
| +--ro nominal-power-spectral-density?
| decimal64
+--:(fiber)
| +--ro fiber
| +--ro type-variety string
| +--ro length decimal64
| +--ro loss-coef decimal64
| +--ro total-loss decimal64
| +--ro pmd? decimal64
| +--ro conn-in? decimal64
| +--ro conn-out? decimal64
+--:(concentratedloss)
+--ro concentratedloss
+--ro loss decimal64
augment /nw:networks/nw:network/nw:node/tet:te
/tet:tunnel-termination-point:
+--ro otsi-group* [otsi-group-id]
| +--ro otsi-group-id int16
| +--ro otsi* [otsi-carrier-id]
| +--ro otsi-carrier-id int16
| +--ro transponder-ref? leafref
| +--ro transceiver-ref? leafref
| +--ro configured-mode? leafref
| +--ro OTSi-carrier-frequency? frequency-thz
| +--ro tx-channel-power? dbm-t
| +--ro rx-channel-power? dbm-t
| +--ro rx-total-power? dbm-t
+--ro transponder* [transponder-id]
+--ro transponder-id uint32
+--ro transceiver* [transceiver-id]
+--ro transceiver-id uint32
+--ro supported-modes
+--ro supported-mode* [mode-id]
+--ro mode-id string
+--ro (mode)
+--:(G.698.2)
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| +--ro standard-mode? standard-mode
+--:(organizational-mode)
| +--ro organizational-mode
| +--ro operational-mode?
| | operational-mode
| +--ro organization-identifier?
| | organization-identifier
| +--ro min-central-frequency?
| | frequency-thz
| +--ro max-central-frequency?
| | frequency-thz
| +--ro minimum-channel-spacing?
| | frequency-ghz
| +--ro tx-channel-power-min? dbm-t
| +--ro tx-channel-power-max? dbm-t
| +--ro rx-channel-power-min? dbm-t
| +--ro rx-channel-power-max? dbm-t
| +--ro rx-total-power-max? dbm-t
+--:(explicit-mode)
+--ro explicit-mode
+--ro supported-modes
| +--ro supported-application-codes*
| | -> ../../../mode-id
| +--ro supported-organizational-modes*
| -> ../../../mode-id
+--ro line-coding-bitrate?
| identityref
+--ro max-polarization-mode-dispersion?
| decimal64
+--ro max-chromatic-dispersion?
| decimal64
+--ro chromatic-and-polarization-dispersion-penalty* []
| +--ro chromatic-dispersion
| | decimal64
| +--ro polarization-mode-dispersion
| | decimal64
| +--ro penalty
| decimal64
+--ro max-diff-group-delay?
| int32
+--ro max-polarization-dependent-loss?
| decimal64
+--ro available-modulation-type?
| identityref
+--ro OTSi-carrier-bandwidth?
| frequency-ghz
+--ro min-OSNR?
| snr
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+--ro min-Q-factor?
| int32
+--ro available-baud-rate?
| uint32
+--ro available-fec-type?
| identityref
+--ro fec-code-rate?
| decimal64
+--ro fec-threshold?
| decimal64
+--ro min-central-frequency?
| frequency-thz
+--ro max-central-frequency?
| frequency-thz
+--ro minimum-channel-spacing?
| frequency-ghz
+--ro tx-channel-power-min?
| dbm-t
+--ro tx-channel-power-max?
| dbm-t
+--ro rx-channel-power-min?
| dbm-t
+--ro rx-channel-power-max?
| dbm-t
+--ro rx-total-power-max?
dbm-t
augment /nw:networks/nw:network/nw:node/tet:te
/tet:tunnel-termination-point:
+--ro sliceable-transponder-list* [carrier-id]
+--ro carrier-id uint32
augment /nw:networks/nw:network/nw:node/tet:te
/tet:te-node-attributes:
+--ro roadm-path-impairments* [roadm-path-impairments-id]
+--ro roadm-path-impairments-id uint32
+--ro (impairment-type)?
+--:(roadm-express-path)
| +--ro roadm-express-path
| +--ro roadm-pmd? decimal64
| +--ro roadm-cd? decimal64
| +--ro roadm-pdl? decimal64
| +--ro roadm-inband-crosstalk? decimal64
| +--ro roadm-maxloss? decimal64
+--:(roadm-add-path)
| +--ro roadm-add-path
| +--ro roadm-pmd? decimal64
| +--ro roadm-cd? decimal64
| +--ro roadm-pdl? decimal64
| +--ro roadm-inband-crosstalk? decimal64
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| +--ro roadm-maxloss? decimal64
| +--ro roadm-pmax? decimal64
| +--ro roadm-osnr? l0-types-ext:snr
| +--ro roadm-noise-figure? decimal64
+--:(roadm-drop-path)
+--ro roadm-drop-path
+--ro roadm-pmd? decimal64
+--ro roadm-cd? decimal64
+--ro roadm-pdl? decimal64
+--ro roadm-inband-crosstalk? decimal64
+--ro roadm-maxloss? decimal64
+--ro roadm-minloss? decimal64
+--ro roadm-typloss? decimal64
+--ro roadm-pmin? decimal64
+--ro roadm-pmax? decimal64
+--ro roadm-ptyp? decimal64
+--ro roadm-osnr? l0-types-ext:snr
+--ro roadm-noise-figure? decimal64
augment /nw:networks/nw:network/nw:node/tet:te
/tet:information-source-entry/tet:connectivity-matrices:
+--ro roadm-path-impairments? leafref
augment /nw:networks/nw:network/nw:node/tet:te
/tet:information-source-entry/tet:connectivity-matrices
/tet:connectivity-matrix:
+--ro roadm-path-impairments? leafref
augment /nw:networks/nw:network/nw:node/tet:te
/tet:te-node-attributes/tet:connectivity-matrices:
+--ro roadm-path-impairments?
-> ../../roadm-path-impairments/roadm-path-impairments-id
augment /nw:networks/nw:network/nw:node/tet:te
/tet:te-node-attributes/tet:connectivity-matrices
/tet:connectivity-matrix:
+--ro roadm-path-impairments? leafref
augment /nw:networks/nw:network/nw:node/tet:te
/tet:tunnel-termination-point
/tet:local-link-connectivities:
+--ro add-path-impairments? leafref
+--ro drop-path-impairments? leafref
augment /nw:networks/nw:network/nw:node/tet:te
/tet:tunnel-termination-point
/tet:local-link-connectivities
/tet:local-link-connectivity:
+--ro add-path-impairments? leafref
+--ro drop-path-impairments? leafref
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4. Optical Impairment Topology YANG Model
[Editor's note: YANG code below may have to be updated before
submission!]
<CODE BEGINS>
module ietf-optical-impairment-topology {
yang-version 1.1;
namespace "urn:ietf:params:xml"
+":ns:yang:ietf-optical-impairment-topology";
prefix "optical-imp-topo";
import ietf-network {
prefix "nw";
}
import ietf-network-topology {
prefix "nt";
}
import ietf-te-topology {
prefix "tet";
}
import ietf-layer0-types {
prefix "l0-types";
}
import ietf-layer0-types-ext {
prefix "l0-types-ext";
}
organization
"IETF CCAMP Working Group";
contact
"Editor: Young Lee <younglee.tx@gmail.com>
Editor: Haomian Zheng <zhenghaomian@huawei.com>
Editor: Nicola Sambo <nicosambo@gmail.com>
Editor: Victor Lopez <victor.lopezalvarez@telefonica.com>
Editor: Gabriele Galimberti <ggalimbe@cisco.com>
Editor: Giovanni Martinelli <giomarti@cisco.com>
Editor: Jean-Luc Auge <jeanluc.auge@orange.com>
Editor: Le Rouzic Esther <esther.lerouzic@orange.com>
Editor: Julien Meuric <julien.meuric@orange.com>
Editor: Italo Busi <Italo.Busi@huawei.com>
Lee, et al. Expires August 26, 2021 [Page 27]
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Editor: Dieter Beller <dieter.beller@nokia.com>
Editor: Sergio Belotti <Sergio.belotti@nokia.com>
Editor: Griseri Enrico <enrico.griseri@nokia.com>
Editor: Gert Grammel <ggrammel@juniper.net>";
description
"This module contains a collection of YANG definitions for
impairment-aware optical networks.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD
License set forth in Section 4.c of the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove
// this note
// replace the revision date with the module publication date
// the format is (year-month-day)
revision 2021-02-16 {
description
"Initial Version";
reference
"RFC XXXX: A Yang Data Model for Impairment-aware
Optical Networks";
}
// grouping
grouping transponder-attributes {
description "Configuration of an optical transponder";
leaf-list available-modulation-types {
type identityref {
base l0-types-ext:modulation;
}
config false;
description
"List of modulation types the OTSi supports";
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}
leaf configured-modulation-type {
type identityref {
base l0-types-ext:modulation;
}
config false;
description
"Currently configured OTSi modulation type";
}
leaf-list available-baud-rates {
type uint32;
units Bd;
config false;
description
"list of available baud-rates.
Baud-rate is the unit for
symbol rate or modulation rate
in symbols per second or
pulses per second.
It is the number of distinct symbol
changes (signal events) made to the
transmission medium
per second in a digitally
modulated signal or a line code";
}
leaf configured-baud-rate {
type uint32;
units Bd;
config false;
description "configured baud-rate";
}
leaf-list available-FEC-types {
type identityref {
base l0-types-ext:fec-type;
}
config false;
description "List determining all the available FEC";
}
leaf configured-FEC-type {
type identityref {
base l0-types-ext:fec-type;
}
config false;
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description
"FEC type configured for the transponder";
}
leaf FEC-code-rate {
type decimal64 {
fraction-digits 8;
range "0..max";
}
config false;
description "FEC-code-rate";
}
leaf FEC-threshold {
type decimal64 {
fraction-digits 8;
range "0..max";
}
config false;
description
"Threshold on the BER, for which FEC
is able to correct errors";
}
}
grouping sliceable-transponder-attributes {
description
"Configuration of a sliceable transponder.";
list sliceable-transponder-list {
key "carrier-id";
config false;
description "List of carriers";
leaf carrier-id {
type uint32;
config false;
description "Identifier of the carrier";
}
}
}
grouping optical-fiber-data {
description
"optical link (fiber) attributes with impairment data";
leaf fiber-type {
type fiber-type;
config false;
description "fiber-type";
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}
leaf span-length {
type decimal64 {
fraction-digits 2;
}
units "km";
config false;
description "the lenght of the fiber span in km";
}
leaf input-power {
type decimal64 {
fraction-digits 2;
}
units "dBm";
config false;
description
"Average input power level estimated at the receiver
of the link";
}
leaf output-power {
type decimal64 {
fraction-digits 2;
}
units "dBm";
description
"Mean launched power at the transmitter of the link";
}
leaf pmd {
type decimal64 {
fraction-digits 8;
range "0..max";
}
units "ps/(km)^0.5";
config false;
description
"Polarization Mode Dispersion";
}
leaf cd {
type decimal64 {
fraction-digits 5;
}
units "ps/nm/km";
config false;
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description
"Cromatic Dispersion";
}
leaf osnr {
type l0-types-ext:snr;
config false;
description
"Optical Signal-to-Noise Ratio (OSNR) estimated
at the receiver";
}
leaf sigma {
type decimal64 {
fraction-digits 5;
}
units "dB";
config false;
description
"sigma in the Gausian Noise Model";
}
}
grouping optical-channel-data {
description
"optical impairment data per channel/wavelength";
leaf bit-rate {
type decimal64 {
fraction-digits 8;
range "0..max";
}
units "Gbit/s";
config false;
description
"Gross bit rate";
}
leaf BER {
type decimal64 {
fraction-digits 18;
range "0..max";
}
config false;
description
"BER (Bit Error Rate)";
}
leaf ch-input-power {
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type decimal64 {
fraction-digits 2;
}
units "dBm";
config false;
description
"Per channel average input power level
estimated at the receiver of the link";
}
leaf ch-pmd {
type decimal64 {
fraction-digits 8;
range "0..max";
}
units "ps/(km)^0.5";
config false;
description
"per channel Polarization Mode Dispersion";
}
leaf ch-cd {
type decimal64 {
fraction-digits 5;
}
units "ps/nm/km";
config false;
description
"per channel Cromatic Dispersion";
}
leaf ch-osnr {
type l0-types-ext:snr;
config false;
description
"per channel Optical Signal-to-Noise Ratio
(OSNR) estimated at the receiver";
}
leaf q-factor {
type decimal64 {
fraction-digits 5;
}
units "dB";
config false;
description
"q-factor estimated at the receiver";
}
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}
/*
* Identities
*/
identity type-power-mode {
description
"power equalization mode used within the
OMS and its elements";
}
identity power-spectral-density {
base type-power-mode;
description
"all elements must use power spectral density (W/Hz)";
}
identity channel-power {
base type-power-mode;
description
"all elements must use power (dBm)";
}
/*
* Typedefs
*/
typedef fiber-type {
type enumeration {
enum G.652 {
description "G.652 Standard Singlemode Fiber";
}
enum G.654 {
description "G.654 Cutoff Shifted Fiber";
}
enum G.653 {
description "G.653 Dispersion Shifted Fiber";
}
enum G.655 {
description "G.655 Non-Zero Dispersion Shifted Fiber";
}
enum G.656 {
description "G.656 Non-Zero Dispersion for Wideband
Optical Transport";
}
enum G.657 {
description "G.657 Bend-Insensitive Fiber";
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}
}
description
"ITU-T based fiber-types";
}
/*
* Groupings
*/
grouping amplifier-params {
description "describes parameters for an amplifier";
container amplifier{
description
"amplifier type, operatonal parameters are described.";
leaf type-variety {
type string ;
mandatory true ;
description
"String identifier of amplifier type referencing
a specification in a separate equipment catalog";
}
container operational {
description "amplifier operational parameters";
list amplifier-element {
description
"The list of parallel amplifier elements within an
amplifier used to amplify different frequency ranges.";
leaf name {
type string;
description
"The name of the amplifier element as specified in
the vendor's specification associated with the
type-variety.";
}
container frequency-range {
description
"The frequency range amplified by the amplifier
element.";
leaf lower-frequency {
type l0-types-ext:frequency-thz;
description
"The lower frequency boundary of the
frequency range.";
}
leaf upper-frequency {
type l0-types-ext:frequency-thz;
description
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"The upper frequency boundary of the
frequency range.";
}
}
leaf actual-gain {
type decimal64 {
fraction-digits 2;
}
units dB ;
mandatory true ;
description "..";
}
leaf tilt-target {
type decimal64 {
fraction-digits 2;
}
mandatory true ;
description "..";
}
leaf out-voa {
type decimal64 {
fraction-digits 2;
}
units dB;
mandatory true;
description "..";
}
leaf in-voa {
type decimal64 {
fraction-digits 2;
}
units dB;
mandatory true;
description "..";
}
uses power-param;
} // list amplifier-element
} // container operational
} // container amplifier
} // grouping amplifier-params
grouping fiber-params {
description
"String identifier of fiber type referencing a
specification in a separate equipment catalog";
container fiber {
description "fiber characteristics";
leaf type-variety {
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type string ;
mandatory true ;
description "fiber type";
}
leaf length {
type decimal64 {
fraction-digits 2;
}
units km;
mandatory true ;
description "length of fiber";
}
leaf loss-coef {
type decimal64 {
fraction-digits 2;
}
units dB/km;
mandatory true ;
description "loss coefficient of the fiber";
}
leaf total-loss {
type decimal64 {
fraction-digits 2;
}
units dB;
mandatory true ;
description
"includes all losses: fiber loss and conn-in and
conn-out losses";
}
leaf pmd{
type decimal64 {
fraction-digits 2;
}
units sqrt(ps);
description "pmd of the fiber";
}
leaf conn-in{
type decimal64 {
fraction-digits 2;
}
units dB;
description "connector-in";
}
leaf conn-out{
type decimal64 {
fraction-digits 2;
}
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units dB;
description "connector-out";
}
}
}
grouping roadm-express-path {
description "roadm express path optical impairments";
container roadm-express-path {
description "roadm parameters per express path";
leaf roadm-pmd {
type decimal64 {
fraction-digits 8;
range "0..max";
}
units "ps/(km)^0.5";
description
"Polarization Mode Dispersion";
}
leaf roadm-cd {
type decimal64 {
fraction-digits 5;
}
units "ps/nm";
description "Chromatic Dispersion";
}
leaf roadm-pdl {
type decimal64 {
fraction-digits 2;
}
units dB ;
description "Polarization dependent loss";
}
leaf roadm-inband-crosstalk {
type decimal64 {
fraction-digits 2;
}
units dB;
description
"In-band crosstalk, or coherent crosstalk, can occur in
components that can have multiple same wavelength inputs
with the inputs either routed to different output ports,
or all but 1 blocked";
}
leaf roadm-maxloss {
type decimal64 {
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fraction-digits 2;
}
units dB;
description
"This is the maximum expected add path loss from the
ROADM ingress to the ROADM egress
assuming no additional add path loss is added";
}
}
}
grouping roadm-add-path {
description "roadm add block path optical impairments";
container roadm-add-path {
description "roadm optical impairment parameters
per add path";
leaf roadm-pmd {
type decimal64 {
fraction-digits 8;
range "0..max";
}
units "ps";
description
"Polarization Mode Dispersion";
}
leaf roadm-cd {
type decimal64 {
fraction-digits 5;
}
units "ps/nm";
description "Cromatic Dispersion";
}
leaf roadm-pdl {
type decimal64 {
fraction-digits 2;
}
units dB ;
description "Polarization dependent loss";
}
leaf roadm-inband-crosstalk {
type decimal64 {
fraction-digits 2;
}
units dB ;
description
"In-band crosstalk, or coherent crosstalk,
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can occur in components that can have multiple same
wavelength inputs,with the inputs either
routed to different output ports,
or all but 1 blocked.
In the case of add path it is the total
of the add block
+ egress WSS crosstalk contributions.";
}
leaf roadm-maxloss {
type decimal64 {
fraction-digits 2;
}
units dB ;
description
"This is the maximum expected add path loss from
the add/drop port input to the ROADM egress,
assuming no additional add path loss is added.
This is used to establish the minimum required
transponder output power required
to hit the ROADM egress target power
levels and preventing
to hit the WSS attenuation limits.
If the add path contains an internal amplifier
this loss value should be based
on worst case expected amplifier gain due to
ripple or gain uncertainty";
}
leaf roadm-pmax {
type decimal64 {
fraction-digits 2;
}
units dBm ;
description
"This is the maximum (per carrier) power level
permitted at the add block input ports,
that can be handled by the ROADM node.
This may reflect either add amplifier power
contraints or WSS adjustment limits.
Higher power transponders would need to have
their launch power reduced
to this value or lower";
}
leaf roadm-osnr {
type l0-types-ext:snr;
description
"Optical Signal-to-Noise Ratio (OSNR).
If the add path contains the ability to adjust the
carrier power levels into an add path amplifier
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(if present) to a target value,
this reflects the OSNR contribution of the
add amplifier assuming this target value is obtained.
The worst case OSNR based on the input power and
NF calculation method, and this value, should be used
(if both are defined).";
}
leaf roadm-noise-figure {
type decimal64 {
fraction-digits 5;
}
units "dB";
description
"Noise Figure. If the add path contains an amplifier,
this is the noise figure of that amplifier inferred
to the add port.
This permits add path OSNR calculation based
on the input power levels to the add block
without knowing the ROADM path losses to
the add amplifier.";
}
}
}
grouping roadm-drop-path {
description "roadm drop block path optical impairments";
container roadm-drop-path {
description "roadm optical impairment parameters
per drop path";
leaf roadm-pmd {
type decimal64 {
fraction-digits 8;
range "0..max";
}
units "ps/(km)^0.5";
description
"Polarization Mode Dispersion";
}
leaf roadm-cd {
type decimal64 {
fraction-digits 5;
}
units "ps/nm";
description "Chromatic Dispersion";
}
leaf roadm-pdl {
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type decimal64 {
fraction-digits 2;
}
units dB ;
description "Polarization dependent loss";
}
leaf roadm-inband-crosstalk {
type decimal64 {
fraction-digits 2;
}
units dB;
description
"In-band crosstalk, or coherent crosstalk, can occur in
components that can have multiple same wavelength
inputs,with the inputs either routed to different
output ports,or all but 1 blocked.
In the case of drop path it is the total
of the ingress
to drop e.g. WSS and drop block crosstalk
contributions.";
}
leaf roadm-maxloss {
type decimal64 {
fraction-digits 2;
}
units dB ;
description
"The net loss from the ROADM input,to the output
of the drop block.
If ROADM ingress to drop path includes an amplifier,
the amplifier gain reduces the net loss.
This is before any additional drop path attenuation
that may be required
due to drop amplifier power contraints.
The max value correspond to worst case expected loss,
including amplifier gain ripple or uncertainty.
It is the maximum output power of the drop
amplifier.";
}
leaf roadm-minloss {
type decimal64 {
fraction-digits 2;
}
units dB ;
description
"The net loss from the ROADM input, to the
output of the drop block.
If this ROADM ingress to drop path includes
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an amplifier,the amplifier gain reduces the net loss.
This is before any additional drop path attenuation
that may be required due to drop amplifier power
contraints.
The min value correspond to best case expected loss,
including amplifier gain ripple or uncertainty.";
}
leaf roadm-typloss {
type decimal64 {
fraction-digits 2;
}
units dB ;
description
"The net loss from the ROADM input,
to the output of the drop block.
If this ROADM ingress to drop path
includes an amplifier,
the amplifier gain reduces the net loss.
This is before any additional drop path
attenuation
that may be required due to drop amplifier
power contraints.
The typ value correspond to typical case
expected loss.";
}
leaf roadm-pmin {
type decimal64 {
fraction-digits 2;
}
units dBm ;
description
"If the drop path has additional loss
that is added, for example,
to hit target power levels into a
drop path amplifier, or simply, to reduce the
power of a strong carrier
(due to ripple,for example),
then the use of the ROADM input power levels and
the above drop losses is not appropriate.
This parameter corresponds to the min per
carrier power levels
expected at the output of the drop block.
A detail example of the comparison using
these parameters is
detailed in section xxx of the document yyy.";
}
leaf roadm-pmax {
type decimal64 {
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fraction-digits 2;
}
units dBm ;
description
"If the drop path has additional loss that is added,
for example, to hit target power levels into a
drop path amplifier,or simply,to reduce the power
of a strong carrier(due to ripple,for example),
then the use of the ROADM input power levels and the
above drop losses is not appropriate.
This parameter corresponds to the best case per
carrier power levels expected at the output of the
drop block.
A detail example of the comparison using
these parameters
is detailed in section xxx of the document yyy";
}
leaf roadm-ptyp {
type decimal64 {
fraction-digits 2;
}
units dBm ;
description
"If the drop path has additional loss that is added,
for example, to hit target power levels into a
drop path amplifier,or simply,to reduce the
power of a strong carrier(due to ripple,for example),
then the use of the ROADM input power levels and
the above drop losses is not appropriate.
This parameter corresponds to the typical case
per carrier power levels expected
at the output of the drop block.";
}
leaf roadm-osnr {
type l0-types-ext:snr;
description
"Optical Signal-to-Noise Ratio (OSNR).
Expected OSNR contribution of the drop path
amplifier(if present)
for the case of additional drop path loss
(before this amplifier)
in order to hit a target power level (per carrier).
If both, the OSNR based on the ROADM
input power level
(Pcarrier =
Pref+10Log(carrier-baudrate/ref-baud) + delta-power)
and the input inferred NF(NF.drop),
and this OSNR value, are defined,
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the minimum value between these two should be used";
}
leaf roadm-noise-figure {
type decimal64 {
fraction-digits 5;
}
units "dB";
description
"Drop path Noise Figure.
If the drop path contains an amplifier,
this is the noise figure
of that amplifier, inferred to the
ROADM ingress port.
This permits to determine
amplifier OSNR contribution
without having to specify the
ROADM node's losses to that amplifier.
This applies for the case of no
additional drop path loss,
before the amplifier, in order to reduce the power
of the carriers to a target value";
}
}
}
grouping concentratedloss-params{
description "concentrated loss";
container concentratedloss{
description "concentrated loss";
leaf loss {
type decimal64 {
fraction-digits 2;
}
units dB ;
mandatory true;
description "..";
}
}
}
grouping power-param{
description
"optical power or PSD after the ROADM or after the out-voa";
choice power-param {
description
"select the mode: channel power or power spectral density";
case channel-power {
/* when "equalization-mode='channel-power'"; */
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leaf nominal-channel-power{
type decimal64 {
fraction-digits 1;
}
units dBm ;
description
" Reference channel power after the ROADM or after
the out-voa. ";
}
}
case power-spectral-density{
/* when "equalization-mode='power-spectral-density'"; */
leaf nominal-power-spectral-density{
type decimal64 {
fraction-digits 16;
}
units W/Hz ;
description
" Reference power spectral density after
the ROADM or after the out-voa.
Typical value : 3.9 E-14, resolution 0.1nW/MHz";
}
}
}
}
grouping oms-general-optical-params {
description "OMS link optical parameters";
leaf generalized-snr {
type l0-types-ext:snr;
description "generalized snr";
}
leaf equalization-mode{
type identityref {
base type-power-mode;
}
mandatory true;
description "equalization mode";
}
uses power-param;
}
grouping OTSiG {
description "OTSiG definition , representing client
digital information stream supported by 1 or more OTSi";
list otsi {
key "otsi-carrier-id";
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config false;
description
"list of OTSi contained in 1 OTSiG.
The list could also be of only 1 element";
leaf otsi-carrier-id {
type int16;
description "OTSi carrier-id";
}
/*any OTSi as signal generated by transceiver and*/
/* attached to a transponder.*/
leaf transponder-ref {
type leafref {
path "/nw:networks/nw:network/nw:node/tet:te" +
"/tet:tunnel-termination-point" +
"/transponder/transponder-id";
}
description
"Reference to the configured transponder";
}
leaf transceiver-ref {
type leafref {
path "/nw:networks/nw:network/nw:node/tet:te" +
"/tet:tunnel-termination-point/"
+"transponder[transponder-id=current()"
+"/../transponder-ref]/"
+ "transceiver/transceiver-id" ;
}
description
"Reference to the configured transceiver " ;
}
leaf configured-mode {
type leafref {
path "/nw:networks/nw:network/nw:node/tet:te" +
"/tet:tunnel-termination-point/"
+"transponder[transponder-id=current()"
+"/../transponder-ref]/"+
"transceiver[transceiver-id=current()/"+
"../transceiver-ref]/supported-modes/"+
"supported-mode/mode-id";
}
description
"Reference to the configured mode for transceiver
compatibility approach";
}
uses l0-types-ext:common-transceiver-configured-param;
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} // OTSi list
} // OTSiG grouping
grouping media-channel-groups {
description "media channel groups";
list media-channel-group {
key "i";
description
"list of media channel groups";
leaf i {
type int16;
description "index of media channel group member";
}
list media-channels {
key "flexi-n";
description
"list of media channels represented as (n,m)";
// this grouping add both n.m values
uses l0-types:flexi-grid-frequency-slot;
leaf OTSiG-ref {
type leafref {
path "/nw:networks/nw:network/nw:node/tet:te" +
"/tet:tunnel-termination-point" +
"/otsi-group/otsi-group-id" ;
}
description
"Reference to the otsi-group list to get otsi-group
identifier of the
OTSiG carried by this media channel
that reports the transient stat";
}
leaf OTSi-ref {
type leafref {
path "/nw:networks/nw:network/nw:node/tet:te" +
"/tet:tunnel-termination-point/"
+"otsi-group[otsi-group-id=current()"
+"/../OTSiG-ref]/"
+ "otsi/otsi-carrier-id" ;
}
description
"Reference to the otsi list supporting
the related OTSiG to get otsi identifier";
}
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} // media channels list
} // media-channel-groups list
} // media media-channel-groups grouping
grouping oms-element {
description "OMS description";
list OMS-elements {
key "elt-index";
description
"defines the spans and the amplifier blocks of
the amplified lines";
leaf elt-index {
type uint16;
description
"ordered list of Index of OMS element
(whether it's a Fiber, an EDFA or a
Concentratedloss)";
}
leaf oms-element-uid {
type string;
description
"unique id of the element if it exists";
}
choice element {
mandatory true;
description "OMS element type";
case amplifier {
uses amplifier-params ;
}
case fiber {
uses fiber-params ;
}
case concentratedloss {
uses concentratedloss-params ;
}
}
}
}
/* Data nodes */
augment "/nw:networks/nw:network/nw:network-types"
+ "/tet:te-topology" {
description "optical-impairment topology augmented";
container optical-impairment-topology {
presence "indicates an impairment-aware topology of
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optical networks";
description
"Container to identify impairment-aware topology type";
}
}
augment "/nw:networks/nw:network/nt:link/tet:te"
+ "/tet:te-link-attributes" {
when "/nw:networks/nw:network/nw:network-types"
+"/tet:te-topology/"
+"optical-imp-topo:optical-impairment-topology" {
description
"This augment is only valid for Optical Impairment.";
}
description "Optical Link augmentation for impairment data.";
container OMS-attributes {
config false;
description "OMS attributes";
uses oms-general-optical-params;
uses media-channel-groups;
uses oms-element;
}
}
augment "/nw:networks/nw:network/nw:node/tet:te"
+ "/tet:tunnel-termination-point" {
when "/nw:networks/nw:network/nw:network-types"
+"/tet:te-topology/optical-imp-topo:optical-impairment-topology"{
description
"This augment is only valid for Impairment with non-sliceable
transponder model";
}
description
"Tunnel termination point augmentation for non-sliceable
transponder model.";
list otsi-group {
key "otsi-group-id";
config false;
description
"the list of possible OTSiG representing client digital
stream";
leaf otsi-group-id {
type int16;
description "index of otsi-group element";
}
uses OTSiG;
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} // list of OTSiG
list transponder {
key "transponder-id";
config false;
description "list of transponder";
leaf transponder-id {
type uint32;
description "transponder identifier";
}
list transceiver {
key "transceiver-id";
config false;
description "list of transceiver related to a transponder";
leaf transceiver-id {
type uint32;
description "transceiver identifier";
}
uses l0-types-ext:transceiver-capabilities;
} // end of list of transceiver
} // end list of transponder
} // end of augment
augment "/nw:networks/nw:network/nw:node/tet:te"
+ "/tet:tunnel-termination-point" {
when "/nw:networks/nw:network/nw:network-types"
+"/tet:te-topology/"
+ "optical-imp-topo:optical-impairment-topology" {
description
"This augment is only valid for optical impairment
with sliceable transponder model";
}
description
"Tunnel termination point augmentation for sliceable
transponder model.";
uses sliceable-transponder-attributes;
}
augment "/nw:networks/nw:network/nw:node/tet:te"
+ "/tet:te-node-attributes" {
when "/nw:networks/nw:network/nw:network-types"
+ "/tet:te-topology"
+ "/optical-imp-topo:optical-impairment-topology" {
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description
"This augment is only valid for Optical Impairment
topology";
}
description
"node attributes augmentantion for optical-impairment ROADM
node";
list roadm-path-impairments {
key "roadm-path-impairments-id";
config false;
description "list of set of optical impairments related
to ROADM ";
leaf roadm-path-impairments-id {
type uint32;
description "index of the ROADM path-impairment list";
}
choice impairment-type {
description "type path impairment";
case roadm-express-path {
uses roadm-express-path;
}
case roadm-add-path {
uses roadm-add-path;
}
case roadm-drop-path {
uses roadm-drop-path;
}
}
} // list path impairments
} // augmentation for optical-impairment ROADM
augment "/nw:networks/nw:network/nw:node/tet:te/"
+ "tet:information-source-entry/tet:connectivity-matrices"{
when "/nw:networks/nw:network/nw:network-types"
+ "/tet:te-topology/"
+ "optical-imp-topo:optical-impairment-topology" {
description
"This augment is only valid for Optical Impairment
topology ";
}
description
"Augment default TE node connectivity matrix information
source.";
leaf roadm-path-impairments {
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type leafref {
path "../../../tet:te-node-attributes/"
+ "roadm-path-impairments/roadm-path-impairments-id";
}
description "pointer to the list set of ROADM optical
impairments";
}
} // augmentation connectivity-matrices information-source
augment "/nw:networks/nw:network/nw:node/tet:te/"
+ "tet:information-source-entry/tet:connectivity-matrices/"
+ "tet:connectivity-matrix" {
when "/nw:networks/nw:network/nw:network-types"
+ "/tet:te-topology/"
+ "optical-imp-topo:optical-impairment-topology" {
description
"This augment is only valid for Optical Impairment
topology ";
}
description
"Augment TE node connectivity matrix entry information
source.";
leaf roadm-path-impairments {
type leafref {
path "../../../../tet:te-node-attributes/"
+ "roadm-path-impairments/roadm-path-impairments-id";
}
description "pointer to the list set of ROADM optical
impairments";
}
} // augmentation connectivity-matrix information-source
augment "/nw:networks/nw:network/nw:node/tet:te/"
+ "tet:te-node-attributes/tet:connectivity-matrices" {
when "/nw:networks/nw:network/nw:network-types"
+ "/tet:te-topology/"
+ "optical-imp-topo:optical-impairment-topology" {
description
"This augment is only valid for Optical Impairment
topology ";
}
description
"Augment default TE node connectivity matrix.";
leaf roadm-path-impairments {
type leafref {
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path "../../roadm-path-impairments/"
+ "roadm-path-impairments-id";
}
config false; /*the identifier in the list */
/*"roadm-path-impairments" of ROADM optical impairment*/
/*is read-only as the rest of attributes*/
description "pointer to the list set of ROADM optical
impairments";
}
} // augmentation connectivity-matrices
augment "/nw:networks/nw:network/nw:node/tet:te/"
+ "tet:te-node-attributes/"
+ "tet:connectivity-matrices/tet:connectivity-matrix" {
when "/nw:networks/nw:network/nw:network-types"
+ "/tet:te-topology/"
+ "optical-imp-topo:optical-impairment-topology" {
description
"This augment is only valid for
Optical Impairment topology ";
}
description
"Augment TE node connectivity matrix entry.";
leaf roadm-path-impairments {
type leafref {
path "../../../roadm-path-impairments/"
+ "roadm-path-impairments-id";
}
config false;
description "pointer to the list set of ROADM optical
impairments";
}
} // augmentation connectivity-matrix
augment "/nw:networks/nw:network/nw:node/tet:te/"
+ "tet:tunnel-termination-point/"
+ "tet:local-link-connectivities" {
when "/nw:networks/nw:network/nw:network-types"
+ "/tet:te-topology/"
+ "optical-imp-topo:optical-impairment-topology" {
description
"This augment is only valid for Optical Impairment topology ";
}
description
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"Augment default TTP LLC.";
leaf add-path-impairments {
type leafref {
path "../../../tet:te-node-attributes/"
+ "roadm-path-impairments/roadm-path-impairments-id" ;
}
config false;
description "pointer to the list set of ROADM optical
impairments";
}
leaf drop-path-impairments {
type leafref {
path "../../../tet:te-node-attributes/"
+ "roadm-path-impairments/roadm-path-impairments-id" ;
}
config false;
description "pointer to the list set of ROADM
optical impairments";
}
} // augmentation local-link-connectivities
augment "/nw:networks/nw:network/nw:node/tet:te/"
+ "tet:tunnel-termination-point/"
+ "tet:local-link-connectivities/"
+ "tet:local-link-connectivity" {
when "/nw:networks/nw:network/nw:network-types"
+ "/tet:te-topology/"
+ "optical-imp-topo:optical-impairment-topology" {
description
"This augment is only valid for
Optical Impairment topology ";
}
description
"Augment TTP LLC entry.";
leaf add-path-impairments {
type leafref {
path "../../../../tet:te-node-attributes/"
+ "roadm-path-impairments/roadm-path-impairments-id" ;
}
config false;
description "pointer to the list set of ROADM optical
impairments";
}
leaf drop-path-impairments {
type leafref {
path "../../../../tet:te-node-attributes/"
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+ "roadm-path-impairments/roadm-path-impairments-id" ;
}
config false;
description "pointer to the list set of ROADM optical
impairments";
}
} // augmentation local-link-connectivity
}
<CODE ENDS>
5. Security Considerations
The configuration, state, and action data defined in this document
are designed to be accessed via a management protocol with a secure
transport layer, such as NETCONF [RFC6241]. The NETCONF access
control model [RFC8341] provides the means to restrict access for
particular NETCONF users to a preconfigured subset of all available
NETCONF protocol operations and content.
A number of configuration data nodes defined in this document are
read-only; however, these data nodes may be considered sensitive or
vulnerable in some network environments (TBD).
6. IANA Considerations
This document registers the following namespace URIs in the IETF XML
registry [RFC3688]:
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-optical-impairment-topology
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
This document registers the following YANG modules in the YANG Module
Names registry [RFC7950]:
--------------------------------------------------------------------
name: ietf-optical-impairment-topology
namespace: urn:ietf:params:xml:ns:yang:ietf-optical-impairment-
topology
prefix: optical-imp-topo
reference: RFC XXXX (TDB)
--------------------------------------------------------------------
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7. Acknowledgments
We thank Daniele Ceccarelli and Oscar G. De Dios for useful
discussions and motivation for this work.
8. References
8.1. Normative References
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
[RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
O. Gonzalez de Dios, "YANG Data Model for Traffic
Engineering (TE) Topologies", RFC 8795,
DOI 10.17487/RFC8795, August 2020,
<https://www.rfc-editor.org/info/rfc8795>.
8.2. Informative References
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC6566] Lee, Y., Ed., Bernstein, G., Ed., Li, D., and G.
Martinelli, "A Framework for the Control of Wavelength
Switched Optical Networks (WSONs) with Impairments",
RFC 6566, DOI 10.17487/RFC6566, March 2012,
<https://www.rfc-editor.org/info/rfc6566>.
[RFC7446] Lee, Y., Ed., Bernstein, G., Ed., Li, D., and W. Imajuku,
"Routing and Wavelength Assignment Information Model for
Wavelength Switched Optical Networks", RFC 7446,
DOI 10.17487/RFC7446, February 2015,
<https://www.rfc-editor.org/info/rfc7446>.
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[RFC7579] Bernstein, G., Ed., Lee, Y., Ed., Li, D., Imajuku, W., and
J. Han, "General Network Element Constraint Encoding for
GMPLS-Controlled Networks", RFC 7579,
DOI 10.17487/RFC7579, June 2015,
<https://www.rfc-editor.org/info/rfc7579>.
[RFC7581] Bernstein, G., Ed., Lee, Y., Ed., Li, D., Imajuku, W., and
J. Han, "Routing and Wavelength Assignment Information
Encoding for Wavelength Switched Optical Networks",
RFC 7581, DOI 10.17487/RFC7581, June 2015,
<https://www.rfc-editor.org/info/rfc7581>.
[RFC7698] Gonzalez de Dios, O., Ed., Casellas, R., Ed., Zhang, F.,
Fu, X., Ceccarelli, D., and I. Hussain, "Framework and
Requirements for GMPLS-Based Control of Flexi-Grid Dense
Wavelength Division Multiplexing (DWDM) Networks",
RFC 7698, DOI 10.17487/RFC7698, November 2015,
<https://www.rfc-editor.org/info/rfc7698>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
[RFC8345] Clemm, A., Medved, J., Varga, R., Bahadur, N.,
Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
2018, <https://www.rfc-editor.org/info/rfc8345>.
[RFC8453] Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for
Abstraction and Control of TE Networks (ACTN)", RFC 8453,
DOI 10.17487/RFC8453, August 2018,
<https://www.rfc-editor.org/info/rfc8453>.
[I-D.ietf-ccamp-wson-yang]
Zheng, H., Lee, Y., Guo, A., Lopez, V., and D. King, "A
YANG Data Model for WSON (Wavelength Switched Optical
Networks)", draft-ietf-ccamp-wson-yang-28 (work in
progress), December 2020.
[I-D.ietf-ccamp-layer0-types]
Zheng, H., Lee, Y., Guo, A., Lopez, V., and D. King, "A
YANG Data Model for Layer 0 Types", draft-ietf-ccamp-
layer0-types-09 (work in progress), December 2020.
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[I-D.ietf-ccamp-dwdm-if-param-yang]
Galimberti, G., Kunze, R., Burk, A., Hiremagalur, D., and
G. Grammel, "A YANG model to manage the optical interface
parameters for an external transponder in a WDM network",
draft-ietf-ccamp-dwdm-if-param-yang-05 (work in progress),
November 2020.
[G.807] "Generic functional architecture of the optical media
network", ITU-T Recommendation G.807 - in publication
process, February 2020.
[G.709] "Interfaces for the Optical Transport Network (OTN)",
ITU-T Recommendation G.709, June 2016.
[G.694.1] "Spectral grids for WDM applications: DWDM frequency
grid", ITU-T Recommendation G.694.1, February 2012.
[G.959.1] "Optical transport network physical layer interfaces",
ITU-T Recommendation G.959.1, February 2012.
[G.872] "Architecture of optical transport networks",
ITU-T Recommendation G.872, January 2017.
[G.698.2] "Amplified multichannel dense wavelength division
multiplexing applications with single channel optical
interfaces", ITU-T Recommendation G.698.2, November 2018.
Appendix A. Contributors
Aihua Guo
Huawei Technologies
Email: aguo@futurewei.com
Jonas Martensson
RISE
Email: jonas.martensson@ri.se
Appendix B. Additional Authors
Haomian Zheng
Huawei Technologies
Email: zhenghaomian@huawei.com
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Italo Busi
Huawei Technologies
Email: Italo.Busi@huawei.com
Nicola Sambo
Scuola Superiore Sant'Anna
Email: nicosambo@gmail.com
Giovanni Martinelli
Cisco
Email: giomarti@cisco.com
Esther Le Rouzic
Orange
Email: esther.lerouzic@orange.com
Julien Meuric
Orange
Email: julien.meuric@orange.com
Sergio Belotti
Nokia
Email: Sergio.belotti@nokia.com
Griseri Enrico
Nokia
Email: Enrico.Griseri@nokia.com
Gert Grammel
Juniper
Email: ggrammel@juniper.net
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Authors' Addresses
Young Lee
SKKU (Sung Kyun Kwan University)
Email: younglee.tx@gmail.com
Jean-Luc Auge
Orange
Email: jeanluc.auge@orange.com
Victor Lopez
Telefonica
Email: victor.lopezalvarez@telefonica.com
G. Galimberti
Cisco
Email: ggalimbe@cisco.com
Dieter Beller
Nokia
Email: Dieter.Beller@nokia.com
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