| RFC 9093 | A YANG Data Model for Layer 0 Types | July 2021 |
| Zheng, et al. | Standards Track | [Page] |
This document defines a collection of common data types and groupings in the YANG data modeling language. These derived common types and groupings are intended to be imported by modules that model Layer 0 optical Traffic Engineering (TE) configuration and state capabilities such as Wavelength Switched Optical Networks (WSONs) and flexi-grid Dense Wavelength Division Multiplexing (DWDM) networks.¶
This is an Internet Standards Track document.¶
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.¶
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc9093.¶
Copyright (c) 2021 IETF Trust and the persons identified as the document authors. All rights reserved.¶
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.¶
YANG [RFC7950] is a data modeling language used to model configuration data, state data, Remote Procedure Calls, and notifications for network management protocols such as the Network Configuration Protocol (NETCONF) [RFC6241]. The YANG language supports a small set of built-in data types and provides mechanisms to derive other types from the built-in types.¶
This document introduces a collection of common data types derived from the built-in YANG data types. The derived types and groupings are designed to be the common types applicable for modeling Traffic Engineering (TE) features as well as non-TE features (e.g., physical network configuration aspects) for Layer 0 optical networks in model(s) defined outside of this document. The applicability of Layer 0 types specified in this document includes Wavelength Switched Optical Networks (WSONs) [RFC6163] [ITU-Tg6982] and flexi-grid Dense Wavelength Division Multiplexing (DWDM) networks [RFC7698] [ITU-Tg6941].¶
Refer to [RFC7446] and [RFC7581] for the key terms used in this document, and the terminology for describing YANG data models can be found in [RFC7950].¶
The YANG data model in this document conforms to the Network Management Datastore Architecture defined in [RFC8342].¶
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.¶
| Prefix | YANG module | Reference |
|---|---|---|
| l0-types | ietf-layer0-types | RFC 9093 |
The YANG module "ietf-layer0-types" (defined in Section 3) references [RFC4203], [RFC6163], [RFC6205], [RFC7698], [RFC7699], [RFC8363], [ITU-Tg6941], and [ITU-Tg6942].¶
This document defines a YANG module for common Layer 0 types, ietf-layer0-types. This module is used for WSON and flexi-grid DWDM networks. The "ietf-layer0-types" module contains the following YANG reusable types and groupings:¶
<CODE BEGINS> file "ietf-layer0-types@2021-07-20.yang"
module ietf-layer0-types {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-layer0-types";
prefix l0-types;
organization
"IETF CCAMP Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/ccamp/>
WG List: <mailto:ccamp@ietf.org>
Editor: Haomian Zheng
<mailto:zhenghaomian@huawei.com>
Editor: Young Lee
<mailto:younglee.tx@gmail.com>
Editor: Aihua Guo
<mailto:aihuaguo.ietf@gmail.com>
Editor: Victor Lopez
<mailto:victor.lopez@nokia.com>
Editor: Daniel King
<mailto:d.king@lancaster.ac.uk>";
description
"This module defines Optical Layer 0 types. This module
provides groupings that can be applicable to Layer 0
Fixed Optical Networks (e.g., CWDM (Coarse Wavelength
Division Multiplexing) and DWDM (Dense Wavelength Division
Multiplexing)) and flexi-grid 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
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC 9093; see
the RFC itself for full legal notices.";
revision 2021-07-20 {
description
"Initial version";
reference
"RFC 9093: A YANG Data Model for Layer 0 Types";
}
typedef dwdm-n {
type int16;
description
"The given value 'N' is used to determine the nominal central
frequency.
The nominal central frequency, 'f', is defined by:
f = 193100.000 GHz + N x channel spacing (measured in GHz),
where 193100.000 GHz (193.100000 THz) is the ITU-T 'anchor
frequency' for transmission over the DWDM grid, and where
'channel spacing' is defined by the dwdm-ch-spc-type.";
reference
"RFC6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers,
ITU-T G.694.1 (10/2020): Spectral grids for WDM applications:
DWDM frequency grid";
}
typedef cwdm-n {
type int16;
description
"The given value 'N' is used to determine the nominal central
wavelength.
The nominal central wavelength is defined by:
Wavelength = 1471 nm + N x channel spacing (measured in nm)
where 1471 nm is the conventional 'anchor wavelength' for
transmission over the CWDM grid, and where 'channel spacing'
is defined by the cwdm-ch-spc-type.";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers,
ITU-T G.694.2 (12/2003): Spectral grids for WDM applications:
CWDM wavelength grid";
}
typedef flexi-n {
type int16;
description
"The given value 'N' is used to determine the nominal central
frequency.
The nominal central frequency, 'f', is defined by:
f = 193100.000 GHz + N x channel spacing (measured in GHz),
where 193100.000 GHz (193.100000 THz) is the ITU-T 'anchor
frequency' for transmission over the DWDM grid, and where
'channel spacing' is defined by the flexi-ch-spc-type.
Note that the term 'channel spacing' can be substituted by the
term 'nominal central frequency granularity' defined in
clause 8 of ITU-T G.694.1.";
reference
"RFC 7698: Framework and Requirements for GMPLS-Based Control
of Flexi-Grid Dense Wavelength Division Multiplexing (DWDM)
Networks,
ITU-T G.694.1 (10/2020): Spectral grids for WDM applications:
DWDM frequency grid";
}
typedef flexi-m {
type uint16;
description
"The given value 'M' is used to determine the slot width.
A slot width is defined by:
slot width = M x SWG (measured in GHz),
where SWG is defined by the flexi-slot-width-granularity.";
reference
"RFC 7698: Framework and Requirements for GMPLS-Based Control
of Flexi-Grid Dense Wavelength Division Multiplexing (DWDM)
Networks.
ITU-T G.694.1 (10/2020): Spectral grids for WDM applications:
DWDM frequency grid";
}
identity l0-grid-type {
description
"Layer 0 grid type";
reference
"RFC 6163: Framework for GMPLS and Path Computation Element
(PCE) Control of Wavelength Switched Optical Networks (WSONs),
ITU-T G.694.1 (10/2020): Spectral grids for WDM applications:
DWDM frequency grid,
ITU-T G.694.2 (12/2003): Spectral grids for WDM applications:
CWDM wavelength grid";
}
identity flexi-grid-dwdm {
base l0-grid-type;
description
"Flexi-grid";
reference
"RFC 7698: Framework and Requirements for GMPLS-Based Control
of Flexi-Grid Dense Wavelength Division Multiplexing (DWDM)
Networks,
ITU-T G.694.1 (10/2020): Spectral grids for WDM applications:
DWDM frequency grid";
}
identity wson-grid-dwdm {
base l0-grid-type;
description
"DWDM grid";
reference
"RFC 6163:Framework for GMPLS and Path Computation Element
(PCE) Control of Wavelength Switched Optical Networks (WSONs),
ITU-T G.694.1 (10/2020): Spectral grids for WDM applications:
DWDM frequency grid";
}
identity wson-grid-cwdm {
base l0-grid-type;
description
"CWDM grid";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers,
ITU-T G.694.2 (12/2003): Spectral grids for WDM applications:
CWDM wavelength grid";
}
identity dwdm-ch-spc-type {
description
"DWDM channel-spacing type";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers,
ITU-T G.694.1 (10/2020): Spectral grids for WDM applications:
DWDM frequency grid";
}
identity dwdm-100ghz {
base dwdm-ch-spc-type;
description
"100 GHz channel spacing";
}
identity dwdm-50ghz {
base dwdm-ch-spc-type;
description
"50 GHz channel spacing";
}
identity dwdm-25ghz {
base dwdm-ch-spc-type;
description
"25 GHz channel spacing";
}
identity dwdm-12p5ghz {
base dwdm-ch-spc-type;
description
"12.5 GHz channel spacing";
}
identity flexi-ch-spc-type {
description
"Flexi-grid channel-spacing type";
reference
"RFC 7698: Framework and Requirements for GMPLS-Based Control
of Flexi-Grid Dense Wavelength Division Multiplexing (DWDM)
Networks,
ITU-T G.694.1 (10/2020): Spectral grids for WDM applications:
DWDM frequency grid";
}
identity flexi-ch-spc-6p25ghz {
base flexi-ch-spc-type;
description
"6.25 GHz channel spacing";
}
identity flexi-slot-width-granularity {
description
"Flexi-grid slot width granularity";
}
identity flexi-swg-12p5ghz {
base flexi-slot-width-granularity;
description
"12.5 GHz slot width granularity";
}
identity cwdm-ch-spc-type {
description
"CWDM channel-spacing type";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers,
ITU-T G.694.2 (12/2003): Spectral grids for WDM applications:
CWDM wavelength grid";
}
identity cwdm-20nm {
base cwdm-ch-spc-type;
description
"20nm channel spacing";
}
/* Groupings. */
grouping wson-label-start-end {
description
"The WSON label-start or label-end used to specify WSON label
range.";
choice grid-type {
description
"Label for DWDM or CWDM grid";
case dwdm {
leaf dwdm-n {
when "derived-from-or-self(../../../grid-type,
\"wson-grid-dwdm\")" {
description
"Valid only when grid type is DWDM.";
}
type l0-types:dwdm-n;
description
"The central frequency of DWDM.";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable
(LSC) Label Switching Routers";
}
}
case cwdm {
leaf cwdm-n {
when "derived-from-or-self(../../../grid-type,
\"wson-grid-cwdm\")" {
description
"Valid only when grid type is CWDM.";
}
type l0-types:cwdm-n;
description
"Channel wavelength computing input.";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable
(LSC) Label Switching Routers";
}
}
}
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers";
}
grouping wson-label-hop {
description
"Generic label-hop information for WSON";
choice grid-type {
description
"Label for DWDM or CWDM grid";
case dwdm {
choice single-or-super-channel {
description
"single or super channel";
case single {
leaf dwdm-n {
type l0-types:dwdm-n;
description
"The given value 'N' is used to determine the
nominal central frequency.";
}
}
case super {
leaf-list subcarrier-dwdm-n {
type l0-types:dwdm-n;
description
"The given values 'N' are used to determine the
nominal central frequency for each subcarrier
channel.";
reference
"ITU-T Recommendation G.694.1: Spectral grids for
WDM applications: DWDM frequency grid";
}
}
}
}
case cwdm {
leaf cwdm-n {
type l0-types:cwdm-n;
description
"The given value 'N' is used to determine the nominal
central wavelength.";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable
(LSC) Label Switching Routers";
}
}
}
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers";
}
grouping l0-label-range-info {
description
"Information about Layer 0 label range.";
leaf grid-type {
type identityref {
base l0-grid-type;
}
description
"Grid type";
}
leaf priority {
type uint8;
description
"Priority in Interface Switching Capability Descriptor
(ISCD).";
reference
"RFC 4203: OSPF Extensions in Support of Generalized
Multi-Protocol Label Switching (GMPLS)";
}
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers";
}
grouping wson-label-step {
description
"Label step information for WSON";
choice l0-grid-type {
description
"Grid type: DWDM, CWDM, etc.";
case dwdm {
leaf wson-dwdm-channel-spacing {
when "derived-from-or-self(../../grid-type,
\"wson-grid-dwdm\")" {
description
"Valid only when grid type is DWDM.";
}
type identityref {
base dwdm-ch-spc-type;
}
description
"Label-step is the channel spacing (GHz), e.g., 100.000,
50.000, 25.000, or 12.500 GHz for DWDM.";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable
(LSC) Label Switching Routers";
}
}
case cwdm {
leaf wson-cwdm-channel-spacing {
when "derived-from-or-self(../../grid-type,
\"wson-grid-cwdm\")" {
description
"Valid only when grid type is CWDM.";
}
type identityref {
base cwdm-ch-spc-type;
}
description
"Label-step is the channel spacing (nm), i.e., 20 nm
for CWDM, which is the only value defined for CWDM.";
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable
(LSC) Label Switching Routers";
}
}
}
reference
"RFC 6205: Generalized Labels for Lambda-Switch-Capable (LSC)
Label Switching Routers,
ITU-T G.694.2 (12/2003): Spectral grids for WDM applications:
CWDM wavelength grid";
}
grouping flexi-grid-label-start-end {
description
"The flexi-grid label-start or label-end used to specify
flexi-grid label range.";
leaf flexi-n {
type l0-types:flexi-n;
description
"The given value 'N' is used to determine the nominal
central frequency.";
}
reference
"RFC 7698: Framework and Requirements for GMPLS-Based Control
of Flexi-Grid Dense Wavelength Division Multiplexing (DWDM)
Networks";
}
grouping flexi-grid-frequency-slot {
description
"Flexi-grid frequency slot grouping.";
uses flexi-grid-label-start-end;
leaf flexi-m {
type l0-types:flexi-m;
description
"The given value 'M' is used to determine the slot width.";
}
reference
"RFC 7698: Framework and Requirements for GMPLS-Based Control
of Flexi-Grid Dense Wavelength Division Multiplexing (DWDM)
Networks";
}
grouping flexi-grid-label-hop {
description
"Generic label-hop information for flexi-grid";
choice single-or-super-channel {
description
"single or super channel";
case single {
uses flexi-grid-frequency-slot;
}
case super {
list subcarrier-flexi-n {
key "flexi-n";
uses flexi-grid-frequency-slot;
description
"List of subcarrier channels for flexi-grid super
channel.";
}
}
}
reference
"RFC 7698: Framework and Requirements for GMPLS-Based Control
of Flexi-Grid Dense Wavelength Division Multiplexing (DWDM)
Networks";
}
grouping flexi-grid-label-range-info {
description
"Flexi-grid-specific label range related information";
uses l0-label-range-info;
container flexi-grid {
description
"flexi-grid definition";
leaf slot-width-granularity {
type identityref {
base flexi-slot-width-granularity;
}
default "flexi-swg-12p5ghz";
description
"Minimum space between slot widths. Default is 12.500
GHz.";
reference
"RFC 7698: Framework and Requirements for GMPLS-Based
Control of Flexi-Grid Dense Wavelength Division
Multiplexing (DWDM) Networks";
}
leaf min-slot-width-factor {
type uint16 {
range "1..max";
}
default "1";
description
"A multiplier of the slot width granularity, indicating
the minimum slot width supported by an optical port.
Minimum slot width is calculated by:
Minimum slot width (GHz) =
min-slot-width-factor * slot-width-granularity.";
reference
"RFC 8363: GMPLS OSPF-TE Extensions in Support of Flexi-
Grid Dense Wavelength Division Multiplexing (DWDM)
Networks";
}
leaf max-slot-width-factor {
type uint16 {
range "1..max";
}
must '. >= ../min-slot-width-factor' {
error-message
"Maximum slot width must be greater than or equal to
minimum slot width.";
}
description
"A multiplier of the slot width granularity, indicating
the maximum slot width supported by an optical port.
Maximum slot width is calculated by:
Maximum slot width (GHz) =
max-slot-width-factor * slot-width-granularity
If specified, maximum slot width must be greater than or
equal to minimum slot width. If not specified, maximum
slot width is equal to minimum slot width.";
reference
"RFC 8363: GMPLS OSPF-TE Extensions in Support of Flexi-
Grid Dense Wavelength Division Multiplexing (DWDM)
Networks";
}
}
}
grouping flexi-grid-label-step {
description
"Label step information for flexi-grid";
leaf flexi-grid-channel-spacing {
type identityref {
base flexi-ch-spc-type;
}
default "flexi-ch-spc-6p25ghz";
description
"Label-step is the nominal central frequency granularity
(GHz), e.g., 6.25 GHz.";
reference
"RFC 7699: Generalized Labels for the Flexi-Grid in Lambda
Switch Capable (LSC) Label Switching Routers";
}
leaf flexi-n-step {
type uint8;
description
"This attribute defines the multiplier for the supported
values of 'N'.
For example, given a grid with a nominal central frequency
granularity of 6.25 GHz, the granularity of the supported
values of the nominal central frequency could be 12.5 GHz.
In this case, the values of flexi-n should be even and this
constraint is reported by setting the flexi-n-step to 2.
This attribute is also known as central frequency
granularity in RFC 8363.";
reference
"RFC 8363: GMPLS OSPF-TE Extensions in Support of Flexi-Grid
Dense Wavelength Division Multiplexing (DWDM) Networks";
}
}
}
<CODE ENDS>¶
The YANG module specified in this document defines a schema for data that is designed to be accessed via network management protocols such as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer is the secure transport layer, and the mandatory-to-implement secure transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer is HTTPS, and the mandatory-to-implement secure transport is TLS [RFC8446].¶
The Network Configuration Access Control Model (NACM) [RFC8341] provides the means to restrict access for particular NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. The NETCONF protocol over Secure Shell (SSH) specification [RFC6242] describes a method for invoking and running NETCONF within a Secure Shell (SSH) session as an SSH subsystem.¶
The objects in this YANG module are common data types and groupings. No object in this module can be read or written to. These definitions can be imported and used by other Layer 0 specific modules. It is critical to consider how imported definitions will be utilized and accessible via RPC operations, as the resultant schema will have data nodes that can be writable, or readable, and will have a significant effect on the network operations if used incorrectly or maliciously. All of these considerations belong in the document that defines the modules that import from this YANG module. Therefore, it is important to manage access to resultant data nodes that are considered sensitive or vulnerable in some network environments.¶
The security considerations spelled out in the YANG 1.1 specification [RFC7950] apply for this document as well.¶
IANA has assigned new URIs from the "IETF XML Registry" [RFC3688] as follows:¶
This document registers the following YANG module in the "YANG Module Names" registry [RFC7950].¶
The authors and the working group give their sincere thanks to Robert Wilton for the YANG doctor review and Tom Petch for his comments during the model and document development.¶