Internet Engineering Task Force (IETF) G. Bernstein, Ed.

Internet Engineering Task Force (IETF) G. Bernstein, Ed.
Request for Comments: 7581 Grotto Networking
Category: Standards Track Y. Lee, Ed.
ISSN: 2070-1721 D. Li
Huawei
W. Imajuku
NTT
J. Han
Huawei
June 2015

Routing and Wavelength Assignment Information Encoding for
Wavelength Switched Optical Networks

Abstract

A Wavelength Switched Optical Network (WSON) requires certain key
information fields be made available to facilitate path computation
and the establishment of Label Switched Paths (LSPs). The
information model described in "Routing and Wavelength Assignment
Information Model for Wavelength Switched Optical Networks" (RFC
7446) shows what information is required at specific points in the
WSON. Part of the WSON information model contains aspects that may
be of general applicability to other technologies, while other parts
are specific to WSONs.

This document provides efficient, protocol-agnostic encodings for the
WSON-specific information fields. It is intended that protocol-
specific documents will reference this memo to describe how
information is carried for specific uses. Such encodings can be used
to extend GMPLS signaling and routing protocols. In addition, these
encodings could be used by other mechanisms to convey this same
information to a Path Computation Element (PCE).

Status of This Memo

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 5741.

Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7581.

Bernstein, et al. Standards Track [Page 1]

RFC 7581 WSON Information Encoding June 2015

Copyright Notice

Copyright (c) 2015 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
(http://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.

Bernstein, et al. Standards Track [Page 2]

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Table of Contents

1. Introduction ....................................................4
1.1. Terminology ................................................4
1.2. Conventions Used in This Document ..........................5
2. Resources, Resource Blocks, and the Resource Pool ...............5
2.1. Resource Block Set Field ...................................6
3. Resource Accessibility/Availability .............................7
3.1. Resource Accessibility Field ...............................7
3.2. Resource Wavelength Constraints Field ......................9
3.3. Resource Block Pool State Field ...........................10
3.4. Resource Block Shared Access Wavelength
Availability Field ........................................12
4. Resource Block Information Field ...............................13
4.1. Optical Interface Class List Subfield .....................15
4.1.1. ITU-T G.698.1 Application Code Mapping .............17
4.1.2. ITU-T G.698.2 Application Code Mapping .............18
4.1.3. ITU-T G.959.1 Application Code Mapping .............20
4.1.4. ITU-T G.695 Application Code Mapping ...............22
4.2. Acceptable Client Signal List Subfield ....................23
4.3. Input Bit Rate List Subfield ..............................24
4.4. Processing Capability List Subfield .......................24
5. Security Considerations ........................................26
6. IANA Considerations ............................................26
6.1. Types for Subfields of WSON Resource Block Information ....26
7. References .....................................................27
7.1. Normative References ......................................27
7.2. Informative References ....................................28
Appendix A. Encoding Examples .....................................30
A.1. Wavelength Converter Accessibility Field ..................30
A.2. Wavelength Conversion Range Field .........................32
A.3. An OEO Switch with DWDM Optics ............................32
Contributors ......................................................35
Authors' Addresses ................................................37

Bernstein, et al. Standards Track [Page 3]

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1. Introduction

A Wavelength Switched Optical Network (WSON) is a Wavelength Division
Multiplexing (WDM) optical network in which switching is performed
selectively based on the center wavelength of an optical signal.

[RFC6163] describes a framework for Generalized Multiprotocol Label
Switching (GMPLS) and Path Computation Element (PCE) control of a
WSON. Based on this framework, [RFC7446] describes an information
model that specifies what information is needed at various points in
a WSON in order to compute paths and establish Label Switched Paths
(LSPs).

This document provides efficient encodings of information needed by
the Routing and Wavelength Assignment (RWA) process in a WSON. Such
encodings can be used to extend GMPLS signaling and routing
protocols. In addition, these encodings could be used by other
mechanisms to convey this same information to a PCE. Note that since
these encodings are efficient, they can provide more accurate
analysis of the control-plane communications/processing load for
WSONs looking to utilize a GMPLS control plane.

In parallel to this document, [RFC7579] provides efficient encodings
of information needed by the routing and label assignment process
that are potentially applicable to a wider range of technologies.

1.1. Terminology

Refer to [RFC6163] for definitions of the following:

o Coarse Wavelength Division Multiplexing (CWDM)

o Dense Wavelength Division Multiplexing (DWDM)

o Routing and Wavelength Assignment (RWA)

o Wavelength Division Multiplexing (WDM)

Refer to Section 5 of [RFC7446] for definitions of the following:

o resource

o resource block

o resource pool

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The Optical Interface (OI) Code Point is a unique number that
identifies all information related to optical characteristics of a
physical interface.

1.2. Conventions Used in This Document

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].

2. Resources, Resource Blocks, and the Resource Pool

This section provides encodings for the information fields defined in
[RFC7446] that have applicability to WSON. The encodings are
designed to be suitable for use in the GMPLS routing protocols OSPF
[RFC4203] and IS-IS [RFC5307] and in the PCE Communication Protocol
(PCEP) [RFC5440]. Note that the information distributed in [RFC4203]
and [RFC5307] is arranged via the nesting of sub-TLVs within TLVs;
this document defines elements to be used within such constructs.
Specific constructs of sub-TLVs and the nesting of sub-TLVs of the
information fields defined by this document will be defined in the
respective protocol enhancement documents.

This document defines the following information fields pertaining to
resources within an optical node:

o Resource Accessibility <ResourceAccessibility>

o Resource Wavelength Constraints <ResourceWaveConstraints>

o Resource Block Pool State <RBPoolState>

o Resource Block Shared Access Wavelength Availability
<RBSharedAccessWaveAvailability>

o Resource Block Information <ResourceBlockInfo>

Each of these information fields works with one or more sets of
resources rather than just a single resource block. This motivates
the field definition in Section 2.1.

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2.1. Resource Block Set Field

In a WSON node that includes resource blocks (RBs), denoting subsets
of these blocks allows one to efficiently describe common properties
of the blocks and to describe the structure and characteristics, if
nontrivial, of the resource pool. The Resource Block Set (RB Set)
Field is defined in a similar manner to the label set concept of
[RFC3471].

The information carried in an RB Set Field is defined as follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action |C| Reserved | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Identifier 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Identifier n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Action: 8 bits

0 - Inclusive List

Indicates that the TLV contains one or more RB elements that
are included in the list.

1 - Inclusive Range(s)

Indicates that the TLV contains one or more ranges of RBs.
Each individual range is denoted by two 32-bit RB identifiers.
The first 32 bits is the RB identifier for the start of the
range, and the next 32 bits is the RB identifier for the end
of the range. Note that the Length field is used to determine
the number of ranges.

C (Connectivity bit)

Set to 0 to denote fixed (possibly multicast) connectivity, and
set to 1 to denote potential (switched) connectivity. Used in
Resource Accessibility field. Ignored elsewhere.

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Reserved: 7 bits

This field is reserved. It MUST be set to zero on transmission
and MUST be ignored on receipt.

Length: 16 bits

The total length of this field in bytes.

RB Identifier:

The RB identifier represents the ID of the resource block, which
is a 32-bit integer. The scope of the RB identifier is local to
the node on which it is applied.

Usage Note: The inclusive range "Action" can result in very compact
encoding of resource sets, and it can be advantageous to number
resource blocks in such a way so that status updates (dynamic
information) can take advantage of this efficiency.

3. Resource Accessibility/Availability

This section defines the information fields for dealing with
accessibility and availability of resource blocks within a pool of
resources. These include the <ResourceAccessibility>,
<ResourceWaveConstraints>, <RBPoolState>, and
<RBSharedAccessWaveAvailability> fields.

3.1. Resource Accessibility Field

This information field describes the structure of the resource pool
in relation to the switching device. In particular, it indicates the
ability of an input port to reach sets of resources and the ability
of sets of resources to reach a particular output port. This is the
<PoolInputMatrix> and <PoolOutputMatrix> of [RFC7446].

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The Resource Accessibility field is defined as follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Reserved(8bits)|C| Reserved (23 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Input Link Set Field A #1 |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field A #1 |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Additional Link set and RB set pairs as needed to |
: specify PoolInputMatrix :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Output Link Set Field B #1 |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set B Field #1 (for output connectivity) |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Additional Link Set and RB set pairs as needed to |
: specify PoolOutputMatrix :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where:

C (Connectivity bit): Connectivity indicates how the input/output
ports connect to the resource blocks.

0 - the device is fixed (e.g., a connected port must go through
the resource block)

1 - the device is switched (e.g., a port can be configured to go
through a resource but isn't required)

For the Input and Output Link Set Fields, the Link Set Field encoding
defined in [RFC7579] is to be used.

Note that the direction parameter within the Link Set Field is used
to indicate whether the link set is an input or output link set, and
the bidirectional value for this parameter is not permitted in this
field.

See Appendix A.1 for an illustration of this encoding.

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3.2. Resource Wavelength Constraints Field

Resources, such as wavelength converters, etc., may have limited
input or output wavelength ranges. Additionally, due to the
structure of the optical system, not all wavelengths can necessarily
reach or leave all the resources. These properties are described by
using one or more Resource Wavelength Constraints fields as defined
below:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|I|O|B| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Input Wavelength Constraints |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Output Wavelength Constraints |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

I (Input):

1 - indicates the presence of the Input Wavelength Constraints
field

0 - indicates otherwise.

O (Output):

1 - indicates the presence of the Output Wavelength Constraints
field

0 - indicates otherwise.

B (Both):

1 - indicates that a single Wavelength Constraints field
represents both Input and Output Wavelength Constraints
fields.

Currently, the only valid combinations of (I,O,B) are (1,0,0),
(0,1,0), (1,1,0), and (0,0,1).

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RB Set Field:

A set of resource blocks (RBs) that have the same wavelength
restrictions.

Input Wavelength Constraints:

Indicates the wavelength input restrictions of the RBs in the
corresponding RB set. This field is encoded via the Label Set
Field of [RFC7579].

Output Wavelength Constraints:

Indicates the wavelength output restrictions of RBs in the
corresponding RB set. This field is encoded via the Label Set
Field of [RFC7579].

3.3. Resource Block Pool State Field

The state of the pool is given by the number of resources available
with particular characteristics. A resource block set is used to
encode all or a subset of the resources of interest. The usage state
of resources within a resource block set is encoded as either a list
of 16-bit integer values or a bitmap indicating whether a single
resource is available or in use. The bitmap encoding is appropriate
when resource blocks consist of a single resource. This information
can be relatively dynamic, i.e., can change when a connection (LSP)
is established or torn down.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Usage State |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where:

Action = 0 denotes a list of 16-bit integers, and Action = 1 denotes
a bitmap. Action = 0 covers the case where there are multiple
elements for each resource block. Action = 1 covers the case where
each resource block only contains a single element.

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In both cases, the elements of the RB Set Field are in a one-to-one
correspondence with the values in the RB Usage State area.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action = 0 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB#1 State | RB#2 State |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB#n-1 State | RB#n State or Padding |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

RB#i State (16 bits, unsigned integer): Indicates the number of
resources available in Resource Block #i.

Whether the last 16 bits is a wavelength converter (RB) state or
padding is determined by the number of elements in the RB Set Field.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action = 1 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Usage State Bitmap |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ...... | Padding Bits |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

RB Usage State Bitmap: Variable length but must be a multiple of 4
bytes.

Each bit indicates the usage status of one RB with 0 indicating the
RB is available and 1 indicating the RB is in use. The sequence of
the bitmap is ordered according to the RB Set Field with this
element.

Padding bits: Variable length

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3.4. Resource Block Shared Access Wavelength Availability Field

Resource blocks may be accessed via a shared fiber. If this is the
case, then wavelength availability on these shared fibers is needed
to understand resource availability.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|I|O|B| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Input Available Wavelength Set Field |
: (Optional) :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Output Available Wavelength Set Field |
: (Optional) :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

I (Input):

1 - indicates the presence of the Input Available Wavelength Set
Field.

0 - indicates the absence of the Input Available Wavelength Set
Field.

O (Output):

1 - indicates the presence of the Output Available Wavelength Set
Field.

0 - indicates the absence of the Output Available Wavelength Set
Field.

B (Both):

1 - indicates that a single Available Wavelength Set Field
represents both Input and Output Available Wavelength Set
Fields.

Currently, the only valid combinations of (I,O,B) are (1,0,0),
(0,1,0), (1,1,0), and (0,0,1).

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RB Set Field:

A resource block set in which all the members share the same input
or output fiber or both.

Input Available Wavelength Set Field:

Indicates the wavelengths currently available (not being used) on
the input fiber to this resource block. This field is encoded via
the Label Set Field of [RFC7579].

Output Available Wavelength Set Field:

Indicates the wavelengths currently available (not being used) on
the output fiber from this resource block. This field is encoded
via the Label Set Field of [RFC7579].

4. Resource Block Information Field

As defined in [RFC7446], the Resource Block Information
<ResourceBlockInfo> field is used to represent resource signal
constraints and processing capabilities of a node.

The fundamental properties of a resource block are:

o Optical Interface Class List(s)

o Acceptable Client Signal (shared input, modulation, Forward Error
Correction (FEC), bit rate, and Generalized Protocol Identifier
(G-PID))

o Input Bit Rate

o Processing Capabilities (number of resources in a block,
regeneration, performance monitoring, vendor specific)

<ResourceBlockInfo> fields are used to convey relatively static
information about individual resource blocks, including the resource
block properties and the number of resources in a block.

When more than one <ResourceBlockInfo> field is used, there are no
ordering requirements amongst these fields. The length of the
<ResourceBlockInfo> field is determined from the length of the object
that includes it.

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The <ResourceBlockInfo> field has the following format:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|I|O|B| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Subfield 1 |
: ... :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: : :
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Subfield N |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The RB Set Field is described in Section 2.1.

The shared input or output indication is indicated by the first bit
(I), the second bit (O), and the third bit (B).

I (Input):

1 - indicates if the resource blocks identified in the RB Set
Field utilized a shared fiber for input access.

0 - indicates otherwise.

O (Output):

1 - indicates if the resource blocks identified in the RB Set
Field utilized a shared fiber for output access.

0 - indicates otherwise.

B (Both):

1 - indicates if the resource blocks identified in the RB Set
Field utilized a shared fiber for both input and output
access.

0 - indicates otherwise.

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Currently, the only valid combinations of (I,O,B) are (1,0,0),
(0,1,0), (1,1,0), and (0,0,1).

Zero or more Optional Subfields MAY be present. Optional Subfields
have the following format:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Value... |
. .
. .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The Length field defines the length of the value portion in bytes
(thus, a subfield with no value portion would have a length of zero).
The subfield is padded to 4-byte alignment; padding is not included
in the Length field (so a 3-byte value would have a length of three,
but the total size of the subfield would be 8 bytes). Unrecognized
types are not processed. If multiple subfields of the same type are
present, only the first of the type SHOULD be processed.

The following sub-TLV types are defined:

Value Length Sub-TLV Type

1 variable Optical Interface Class List
2 variable Acceptable Client Signal List
3 variable Input Bit Rate List
4 variable Processing Capability List

See the IANA Considerations section for allocation of new types.

4.1. Optical Interface Class List Subfield

The Optical Interface Class List subfield has the following format:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |I|O|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optical Interface Classes |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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The following I and O combination are defined:

I O
-----
0 0 Invalid

1 0 Optical Interface Class List acceptable in input

0 1 Optical Interface Class List available in output

1 1 Optical Interface Class List available on both input and
output.

The resource block MAY contain one or more lists according to the
input/output flags.

The Optical Interface Classes format is defined as follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S| Reserved | OI Code Points |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optical Interface Class |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optical Interface Class (Cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where the first 32 bits of the encoding shall be used to identify the
semantics of the Optical Interface Class in the following way:

S (Standard bit):

S=0: identifies non-ITU code points

S=1: identifies ITU application codes

With S=0, the OI Code Points field can take the following value:

0: reserved

Future work may add support for vendor-specific application codes
once the ITU-T has completed its work in that area.

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With S=1, the OI Code Points field can take the following values:

0: reserved

1: [G.698.1] application code

2: [G.698.2] application code

3: [G.959.1] application code

4: [G.695] application code

In the case of ITU application codes, the mapping between the string
defining the application code and the 64 bits implementing the
optical interface class is given in the following sections.

4.1.1. ITU-T G.698.1 Application Code Mapping

[G.698.1] defines the following application codes: DScW-ytz(v) and
B-DScW-ytz(v). Where:

B: means Bidirectional

D: means a DWDM application

S: takes values N (narrow spectral excursion) or W (wide spectral
excursion)

c: Channel Spacing (GHz)

W: takes values S (short-haul) or L (long-haul)

y: takes values 1 (NRZ 2.5G) or 2 (NRZ 10G)

t: only D value is defined (link does not contain optical
amplifier)

z: takes values 2 ([G.652] fibre), 3 ([G.653] fibre), or 5
([G.655] fibre)

v: takes values S (Short wavelength), C (Conventional), or L (Long
wavelength)

The F flag indicates the presence or absence of an optional FEC
encoding suffix.

Bernstein, et al. Standards Track [Page 17]

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These get mapped into the 64-bit Optical Interface Class field as
follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|B| D |S| c | W | y | t | z | v | F |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where (values between parentheses refer to ITU-defined values as
reported above):

B: 1 bidirectional, 0 otherwise

D (prefix): 0 reserved, 1 (D)

S: 0 (N), 1 (W)

c: Channel Spacing, 4 bits mapped according to the same definition
as in the third figure in Section 3.2 of [RFC6205] (note that
DWDM spacing applies here).

W: 0 reserved, 2 (S), 3 (L)

y: 0 reserved, 1 (1), 2 (2)

t: 0 reserved, 4 (D)

z: 0 reserved, 2 (2), 3 (3), 5 (5)

v: 0 reserved, 1 (S), 2 (C), 3 (L)

F (suffix): 0 No FEC encoding suffix present, 1 FEC encoding
suffix present

Values not mentioned here are not allowed in this application code;
the last 32 bits are reserved and shall be set to zero.

4.1.2. ITU-T G.698.2 Application Code Mapping

[G.698.2] defines the following application codes: DScW-ytz(v) and
B-DScW-ytz(v). Where:

B: means Bidirectional

D: means a DWDM application

Bernstein, et al. Standards Track [Page 18]

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S: takes values N (narrow spectral excursion) or W (wide spectral
excursion)

c: Channel Spacing (GHz)

W: takes values C (link is dispersion compensated) or U (link is
dispersion uncompensated)

y: takes values 1 (NRZ 2.5G) or 2 (NRZ 10G)

t: takes value A (link may contains optical amplifier)

z: takes values 2 ([G.652] fibre), 3 ([G.653] fibre), or 5
([G.655] fibre)

v: takes values S (Short wavelength), C (Conventional), or L (Long
wavelength)

An optional F can be added to indicate a FEC encoding.

These get mapped into the 64-bit Optical Interface Class field as
follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|B| D |S| c | W | y | t | z | v | F |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where (values between parentheses refer to ITU-defined values as
reported above):

B: 1 bidirectional, 0 otherwise

D (prefix): 0 reserved, 1 (D)

S: 0 (N), 1 (W)

c: Channel Spacing, 4 bits mapped according to the same definition
as in the third figure in Section 3.2 of [RFC6205] (note that
DWDM spacing applies here).

W: 0 reserved, 10 (C), 11 (U)

y: 0 reserved, 1 (1), 2 (2)

Bernstein, et al. Standards Track [Page 19]

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t: 0 reserved, 1 (A)

z: 0 reserved, 2 (2), 3 (3), 5 (5)

v: 0 reserved, 1 (S), 2 (C), 3 (L)

F (suffix): 0 reserved, 1 FEC encoding

Values not mentioned here are not allowed in this application code.
The last 32 bits are reserved and shall be set to zero.

4.1.3. ITU-T G.959.1 Application Code Mapping

[G.959.1] defines the following application codes: PnWx-ytz and
BnWx-ytz. Where:

P,B: when present, indicate Plural or Bidirectional

n: maximum number of channels supported by the application code
(i.e., an integer number)

W: takes values I (intra-office), S (short-haul), L (long-haul), V
(very long-haul), or U (ultra long-haul)

x: maximum number of spans allowed within the application code
(i.e., an integer number)

y: takes values 1 (NRZ 2.5G), 2 (NRZ 10G), 9 (NRZ 25G), 3 (NRZ
40G), or 7 (RZ 40G)

t: takes values A (power levels suitable for a booster amplifier
in the originating ONE and power levels suitable for a pre-
amplifier in the terminating ONE), B (booster amplifier only),
C (pre-amplifier only), or D (no amplifiers)

z: takes values 1 (1310 nm sources on [G.652] fibre), 2 (1550 nm
sources on [G.652] fibre), 3 (1550 nm sources on [G.653]
fibre), or 5 (1550 nm sources on [G.655] fibre).

The following list of suffixes can be added to these application
codes:

F: FEC encoding

D: Adaptive dispersion compensation

E: receiver capable of dispersion compensation

Bernstein, et al. Standards Track [Page 20]

RFC 7581 WSON Information Encoding June 2015

r: reduced target distance

a: power levels appropriate to APD receivers

b: power levels appropriate to PIN receivers

These values are encoded as follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| p | P | n | W | x | reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| y | t | z | suffix | reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where (values between parentheses refer to ITU-defined values as
reported above):

p (prefix): 0 otherwise, 1 Bidirectional (B)

P (optional): 0 not present, 2 (P).

n: maximum number of channels (10 bits, up to 1023 channels)

W: 0 reserved, 1 (I), 2 (S), 3 (L), 4 (V), 5 (U)

x: number of spans (6 bits, up to 64 spans)

y: 0 reserved, 1 (1), 2 (2), 3 (3), 7 (7), 9 (9)

t: 0 reserved, 1 (A), 2 (B), 3 (C), 4 (D)

z: 0 reserved, 1 (1), 2 (2), 3 (3), 5 (5)

suffix: a 6-bit bitmap, where a "1" in the appropriate slot
indicates that the corresponding suffix has been added.

0 1 2 3 4 5
+-+-+-+-+-+-+
|F|D|E|r|a|b|
+-+-+-+-+-+-+

Bernstein, et al. Standards Track [Page 21]

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4.1.4. ITU-T G.695 Application Code Mapping

[G.695] defines the following application codes: CnWx-ytz,
B-CnWx-ytz, and S-CnWx-ytz.

Where the optional prefixes are:

B: Bidirectional

S: a system using a black link approach

And the rest of the application code is defined as:

C: CWDM (Coarse WDM) application

n: maximum number of channels supported by the application code
(i.e., an integer number)

W: takes values S (short-haul) or L (long-haul)

x: maximum number of spans allowed

y: takes values 0 (NRZ 1.25G), 1 (NRZ 2.5G), or 2 (NRZ 10G).

t: takes value D (link does not contain any optical amplifier).

z: takes values 1 (1310 nm region for [G.652] fibre), 2 (ITU-T
[G.652] fibre), 3 ([G.653] fibre), or 5 ([G.655] fibre)

The following list of suffixes can be added to these application
codes:

F: FEC encoding

Since the application codes are very similar to the ones from the
[G.959.1] section, most of the fields are reused. The 64-bit Optical
Interface Class field is encoded as follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| p | C | n | W | x | reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| y | t | z | suffix | reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Bernstein, et al. Standards Track [Page 22]

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Where (values between parentheses refer to ITU-defined values as
reported above):

p: 0 no prefix, 1 (B) bidirectional, 2 (S) black link

C: 0 reserved, 3 (C)

n: maximum number of channels (10 bits, up to 1023 channels)

W: 0 reserved, 1 reserved, 2 (S), 3 (L), > 3 reserved

x: number of spans (6 bits, up to 64 spans)

y: 0 (0), 1 (1), 2 (2), > 2 reserved

t: 4 (D), all other values are reserved

z: 0 reserved, 1 (1), 2 (2), 3 (3)

suffix: a 6-bit bitmap, where a "1" in the appropriate slot
indicates that the corresponding suffix has been added.

0 1 2 3 4 5
+-+-+-+-+-+-+
|F|0|0|0|0|0|
+-+-+-+-+-+-+

4.2. Acceptable Client Signal List Subfield

This subfield contains a list of acceptable input client signal
types.

The acceptable client signal list is a list of Generalized Protocol
Identifiers (G-PIDs).

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Number of G-PIDs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| G-PID #1 | G-PID #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: | :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| G-PID #N | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Bernstein, et al. Standards Track [Page 23]

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Number of G-PIDs: an integer greater than or equal to one.

G-PIDs: assigned by IANA. Many are defined in [RFC3471] and
[RFC4328].

4.3. Input Bit Rate List Subfield

This subfield contains a list of bit rates of each input client
signal type specified in the Input Client Signal List.

The number of Input Bit Rates MUST match the number of G-PIDs.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Input Bit Rate of G-PID #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Input Bit Rate of G-PID #N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Input Bit Rates are in IEEE 754 floating point format [IEEE].

4.4. Processing Capability List Subfield

The Processing Capability List subfield is a list of capabilities
that can be achieved through the referred resources:

1. Regeneration capability

2. Fault and performance monitoring

3. Vendor-specific capability

Fault and performance monitoring and vendor-specific capability have
no additional capability parameters.

Bernstein, et al. Standards Track [Page 24]

RFC 7581 WSON Information Encoding June 2015

The Processing Capability List subfield is defined as:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Processing Cap ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Possible additional capability parameters depending upon |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: the processing ID :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The Processing Cap ID field defines the following processing
capabilities:

0: Reserved

1: Regeneration capability

2: Fault and performance monitoring

3: Vendor-specific capability

When the Processing Cap ID is "Regeneration capability", the
following additional capability parameters are provided in the
following field:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| T | C | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where the T bit indicates the type of regenerator:

T=0: Reserved

T=1: 1R Regenerator

T=2: 2R Regenerator

T=3: 3R Regenerator

Bernstein, et al. Standards Track [Page 25]

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And where the C bit indicates the capability of the regenerator:

C=0: Reserved

C=1: Fixed Regeneration Point

C=2: Selective Regeneration Pools

Note that when the capability of the regenerator is indicated to be
"Selective Regeneration Pools", regeneration pool properties such as
input and output restrictions and availability need to be specified.
These properties will be encoded in the field providing additional
capability parameters, starting with the bits marked Reserved in the
figure immediately above. An additional specification describing the
encoding of these parameters is required before the value C=2 can be
used.

5. Security Considerations

This document defines protocol-independent encodings for WSON
information and does not introduce any security issues.

However, other documents that make use of these encodings within
protocol extensions need to consider the issues and risks associated
with inspection, interception, modification, or spoofing of any of
this information. It is expected that any such documents will
describe the necessary security measures to provide adequate
protection. A general discussion on security in GMPLS networks can
be found in [RFC5920].

6. IANA Considerations

This document introduces a new top-level registry for GMPLS routing
parameters for WSON encoding. This new IANA registry has been
created to make the assignment of a new type and new values for the
new "GMPLS Routing Parameters for WSON" registry. Note that this
registry is only used in routing, not in signaling.

6.1. Types for Subfields of WSON Resource Block Information

Under the new "GMPLS Routing Parameters for WSON" registry, a new
IANA subregistry has been created for nested subfields of the
Resource Block Information field to create a new section named "Types
for Subfields of WSON Resource Block Information Registry". This
registry will be maintained via Standards Action as defined by
[RFC5226].

Bernstein, et al. Standards Track [Page 26]

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The initial values in the registry are as follows:

Value Length Description Reference
----- ------ ------------ ---------
0 Reserved
1 variable Optical Interface Class List [RFC7581]
2 variable Acceptable Client Signal List [RFC7581]
3 variable Input Bit Rate List [RFC7581]
4 variable Processing Capability List [RFC7581]
5-65535 Unassigned

7. References

7.1. Normative References

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.

[RFC4328] Papadimitriou, D., Ed., "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Extensions for G.709 Optical
Transport Networks Control", RFC 4328,
DOI 10.17487/RFC4328, January 2006,
<http://www.rfc-editor.org/info/rfc4328>.

[RFC6205] Otani, T., Ed., and D. Li, Ed., "Generalized Labels for
Lambda-Switch-Capable (LSC) Label Switching Routers",
RFC 6205, DOI 10.17487/RFC6205, March 2011,
<http://www.rfc-editor.org/info/rfc6205>.

[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,
<http://www.rfc-editor.org/info/rfc7446>.

[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,
<http://www.rfc-editor.org/info/rfc7579>.

Bernstein, et al. Standards Track [Page 27]

RFC 7581 WSON Information Encoding June 2015

7.2. Informative References

[G.652] ITU-T, "Characteristics of a single-mode optical fibre and
cable", ITU-T Recommendation G.652, November 2009.

[G.653] ITU-T, "Characteristics of a dispersion-shifted, single-
mode optical fibre and cable", ITU-T Recommendation G.653,
July 2010.

[G.655] ITU-T, "Characteristics of a non-zero dispersion-shifted
single-mode optical fibre and cable", ITU-T Recommendation
G.655, November 2009.

[G.695] ITU-T, "Optical interfaces for coarse wavelength division
multiplexing applications", ITU-T Recommendation G.695,
January 2015.

[G.698.1] ITU-T, "Multichannel DWDM applications with single-channel
optical interfaces", ITU-T Recommendation G.698.1,
November 2009.

[G.698.2] ITU-T, "Amplified multichannel dense wavelength division
multiplexing applications with single channel optical
interfaces", ITU-T Recommendation G.698.2, November 2009.

[G.959.1] ITU-T, "Optical transport network physical layer
interfaces", ITU-T Recommendation G.959.1, February 2012.

[IEEE] IEEE, "IEEE Standard for Binary Floating-Point
Arithmetic", IEEE Standard 754.

[RFC3471] Berger, L., Ed., "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Functional Description",
RFC 3471, DOI 10.17487/RFC3471, January 2003,
<http://www.rfc-editor.org/info/rfc3471>.

[RFC4203] Kompella, K., Ed., and Y. Rekhter, Ed., "OSPF Extensions
in Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 4203, DOI 10.17487/RFC4203, October 2005,
<http://www.rfc-editor.org/info/rfc4203>.

[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
DOI 10.17487/RFC5226, May 2008,
<http://www.rfc-editor.org/info/rfc5226>.

Bernstein, et al. Standards Track [Page 28]

RFC 7581 WSON Information Encoding June 2015

[RFC5307] Kompella, K., Ed., and Y. Rekhter, Ed., "IS-IS Extensions
in Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 5307, DOI 10.17487/RFC5307, October 2008,
<http://www.rfc-editor.org/info/rfc5307>.

[RFC5440] Vasseur, JP., Ed., and JL. Le Roux, Ed., "Path Computation
Element (PCE) Communication Protocol (PCEP)", RFC 5440,
DOI 10.17487/RFC5440, March 2009,
<http://www.rfc-editor.org/info/rfc5440>.

[RFC5511] Farrel, A., "Routing Backus-Naur Form (RBNF): A Syntax
Used to Form Encoding Rules in Various Routing Protocol
Specifications", RFC 5511, DOI 10.17487/RFC5511, April
2009, <http://www.rfc-editor.org/info/rfc5511>.

[RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, DOI 10.17487/RFC5920, July 2010,
<http://www.rfc-editor.org/info/rfc5920>.

[RFC6163] Lee, Y., Ed., Bernstein, G., Ed., and W. Imajuku,
"Framework for GMPLS and Path Computation Element (PCE)
Control of Wavelength Switched Optical Networks (WSONs)",
RFC 6163, DOI 10.17487/RFC6163, April 2011,
<http://www.rfc-editor.org/info/rfc6163>.

Bernstein, et al. Standards Track [Page 29]

RFC 7581 WSON Information Encoding June 2015

Appendix A. Encoding Examples

A.1. Wavelength Converter Accessibility Field

Figure 1 shows a wavelength converter pool architecture known as
"shared per fiber". In this case, the input and output pool matrices
are simply:

+-----+ +-----+
| 1 1 | | 1 0 |
WI =| |, WE =| |
| 1 1 | | 0 1 |
+-----+ +-----+

+-----------+ +------+
| |--------------------->| |
| |--------------------->| C |
/| | |--------------------->| o |
/D+--->| |--------------------->| m |
+ e+--->| | | b |=======>
========>| M| | Optical | +-----------+ | i | Port O1
Port I1 + u+--->| Switch | | WC Pool | | n |
\x+--->| | | +-----+ | | e |
\| | +----+->|WC #1|--+---->| r |
| | | +-----+ | +------+
| | | | +------+
/| | | | +-----+ | | |
/D+--->| +----+->|WC #2|--+---->| C |
+ e+--->| | | +-----+ | | o |
========>| M| | | +-----------+ | m |=======>
Port I2 + u+--->| | | b | Port O2
\x+--->| |--------------------->| i |
\| | |--------------------->| n |
| |--------------------->| e |
| |--------------------->| r |
+-----------+ +------+

Figure 1: An Optical Switch Featuring a Shared Per-Fiber Wavelength
Converter Pool Architecture

Bernstein, et al. Standards Track [Page 30]

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The wavelength converters are resource blocks and the wavelength
converter pool is a resource block pool. This can be encoded as
follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |1| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: I1,I2 can connect to either WC1 or WC2
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0| Reserved | Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1| Reserved | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB ID = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB ID = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: WC1 can only connect to O1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1| Reserved | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0| Reserved | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB ID = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: WC2 can only connect to O2
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1| Reserved | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0| | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB ID = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Bernstein, et al. Standards Track [Page 31]

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A.2. Wavelength Conversion Range Field

This example, based on Figure 1, shows how to represent the
wavelength conversion range of wavelength converters. Suppose the
wavelength range of input and output of WC1 and WC2 are {L1, L2, L3,
L4}:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
Note: WC Set
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1| Reserved | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| WC ID = #1 | WC ID = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: wavelength input range
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 2 | Num Wavelengths = 4 | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: wavelength output range
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 2 | Num Wavelengths = 4 | Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

A.3. An OEO Switch with DWDM Optics

Figure 2 shows an electronic switch fabric surrounded by DWDM optics.
In this example, the electronic fabric can handle either G.709 or
Synchronous Digital Hierarchy (SDH) signals only (2.5 or 10 Gbps).
To describe this node, the following information in Reduced Backus-
Naur Form (RBNF) form [RFC5511] is needed:

<Node_Info> ::= <Node_ID>

[Other GMPLS info-elements]

[<ConnectivityMatrix>...]

[<ResourcePool>]

[<RBPoolState>]

Bernstein, et al. Standards Track [Page 32]

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In this case, there is complete port-to-port connectivity, so the
<ConnectivityMatrix> is not required. In addition, since there are
sufficient ports to handle all wavelength signals, the <RBPoolState>
element is not needed.

Hence, the attention will be focused on the <ResourcePool> field:

<ResourcePool> ::= <ResourceBlockInfo>

[<RBAccessibility>...]

[<ResourceWaveConstraints>...]

/| +-----------+ +-------------+ +------+
/D+--->| +--->|Tunable Laser|-->| |
+ e+--->| | +-------------+ | C |
========>| M| | | ... | o |=======>
Port I1 + u+--->| | +-------------+ | m | Port O1
\x+--->| |--->|Tunable Laser|-->| b |
\| | Electric | +-------------+ +------+
| Switch |
/| | | +-------------+ +------+
/D+--->| +--->|Tunable Laser|-->| |
+ e+--->| | +-------------+ | C |
========>| M| | | ... | o |=======>
Port I2 + u+--->| | +-------------+ | m | Port O2
\x+--->| +--->|Tunable Laser|-->| b |
\| | | +-------------+ +------+
| |
/| | | +-------------+ +------+
/D+--->| |--->|Tunable Laser|-->| |
+ e+--->| | +-------------+ | C |
========>| M| | | ... | o |=======>
Port I3 + u+--->| | +-------------+ | m | Port O3
\x+--->| |--->|Tunable Laser|-->| b |
\| +-----------+ +-------------+ +------+

Figure 2: An Optical Switch Built around
an Electronic Switching Fabric

The resource block information will tell us about the processing
constraints of the receivers, transmitters, and the electronic
switch. The resource availability information, although very simple,
tells us that all signals must traverse the electronic fabric (fixed
connectivity). The resource wavelength constraints are not needed
since there are no special wavelength constraints for the resources
that would not appear as port/wavelength constraints.

Bernstein, et al. Standards Track [Page 33]

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The <ResourceBlockInfo> is encoded as follows:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field |
: (only one resource block in this example with shared |
| input/output case) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1|1|0| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optical Interface Class List(s) |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Input Client Signal Type |
: (G-PIDs for SDH and G.709) :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Input Bit Rate Range List |
: (2.5 Gbps, 10 Gbps) :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Processing Capabilities List |
: Fixed (non optional) 3R regeneration :
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Since there is fixed connectivity to resource blocks (the electronic
switch), the <RBAccessibility> is:

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Connectivity=0|Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Input Link Set Field A #1 |
: (All input links connect to resource) :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RB Set Field A #1 |
: (trivial set only one resource block) :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Output Link Set Field B #1 |
: (All output links connect to resource) :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Bernstein, et al. Standards Track [Page 34]

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Contributors

Diego Caviglia
Ericsson
Via A. Negrone 1/A 16153
Genoa
Italy
Phone: +39 010 600 3736
EMail: [email protected]

Anders Gavler
Acreo AB
Electrum 236
SE - 164 40 Kista
Sweden
EMail: [email protected]

Jonas Martensson
Acreo AB
Electrum 236
SE - 164 40 Kista
Sweden
EMail: [email protected]

Itaru Nishioka
NEC Corp.
1753 Simonumabe
Nakahara-ku, Kawasaki, Kanagawa 211-8666
Japan
Phone: +81 44 396 3287
EMail: [email protected]

Pierre Peloso
ALU
EMail: [email protected]

Cyril Margaria
EMail: [email protected]

Giovanni Martinelli
Cisco
EMail: [email protected]

Gabriele M Galimberti
Cisco
EMail: [email protected]

Bernstein, et al. Standards Track [Page 35]

RFC 7581 WSON Information Encoding June 2015

Lyndon Ong
Ciena Corporation
EMail: [email protected]

Daniele Ceccarelli
Ericsson
EMail: [email protected]

Bernstein, et al. Standards Track [Page 36]

RFC 7581 WSON Information Encoding June 2015

Authors' Addresses

Greg M. Bernstein (editor)
Grotto Networking
Fremont, California
United States
Phone: (510) 573-2237
EMail: [email protected]

Young Lee (editor)
Huawei Technologies
5340 Legacy Drive Build 3
Plano, TX 75024
United States
Phone: (469) 277-5838
EMail: [email protected]

Dan Li
Huawei Technologies Co., Ltd.
F3-5-B R&D Center, Huawei Base,
Bantian, Longgang District
Shenzhen 518129
China
Phone: +86-755-28973237
EMail: [email protected]

Wataru Imajuku
NTT Network Innovation Labs
1-1 Hikari-no-oka, Yokosuka, Kanagawa
Japan
Phone: +81-(46) 859-4315
EMail: [email protected]

Jianrui Han
Huawei Technologies Co., Ltd.
F3-5-B R&D Center, Huawei Base,
Bantian, Longgang District
Shenzhen 518129
China
Phone: +86-755-28972916
EMail: [email protected]

Bernstein, et al. Standards Track [Page 37]