Internet DRAFT - draft-ietf-ccamp-general-constraint-encode
draft-ietf-ccamp-general-constraint-encode
Network Working Group G. Bernstein
Internet Draft Grotto Networking
Intended status: Standards Track Y. Lee
Expires: June 2015 D. Li
Huawei
W. Imajuku
NTT
February 23, 2015
General Network Element Constraint Encoding for GMPLS Controlled
Networks
draft-ietf-ccamp-general-constraint-encode-20.txt
Abstract
Generalized Multiprotocol Label Switching can be used to control a
wide variety of technologies. In some of these technologies, network
elements and links may impose additional routing constraints such as
asymmetric switch connectivity, non-local label assignment, and
label range limitations on links.
This document provides efficient, protocol-agnostic encodings for
general information elements representing connectivity and label
constraints as well as label availability. It is intended that
protocol-specific documents will reference this memo to describe how
information is carried for specific uses.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with
the provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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Internet-Drafts are draft documents valid for a maximum of six
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at any time. It is inappropriate to use Internet-Drafts as
reference material or to cite them other than as "work in progress."
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The list of current Internet-Drafts can be accessed at
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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
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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.
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].
Table of Contents
1. Introduction...................................................3
1.1. Node Switching Asymmetry Constraints......................4
1.2. Non-Local Label Assignment Constraints....................4
2. Encoding.......................................................5
2.1. Connectivity Matrix Field.................................5
2.2. Port Label Restriction Field..............................7
2.2.1. SIMPLE_LABEL.........................................8
2.2.2. CHANNEL_COUNT........................................9
2.2.3. LABEL_RANGE..........................................9
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2.2.4. SIMPLE_LABEL & CHANNEL_COUNT........................10
2.2.5. Link Label Exclusivity..............................10
2.3. Link Set Field...........................................11
2.4. Available Labels Field...................................13
2.5. Shared Backup Labels Field...............................14
2.6. Label Set Field..........................................14
2.6.1. Inclusive/Exclusive Label Lists.....................15
2.6.2. Inclusive/Exclusive Label Ranges....................16
2.6.3. Bitmap Label Set....................................17
3. Security Considerations.......................................17
4. IANA Considerations...........................................18
5. Acknowledgments...............................................18
APPENDIX A: Encoding Examples....................................19
A.1. Link Set Field...........................................19
A.2. Label Set Field..........................................19
A.3. Connectivity Matrix......................................20
A.4. Connectivity Matrix with Bi-directional Symmetry.........23
A.5. Priority Flags in Available/Shared Backup Labels.........25
6. References....................................................27
6.1. Normative References.....................................27
6.2. Informative References...................................28
7. Contributors..................................................29
Authors' Addresses...............................................30
1. Introduction
Some data plane technologies that wish to make use of a GMPLS
control plane contain additional constraints on switching capability
and label assignment. In addition, some of these technologies must
perform non-local label assignment based on the nature of the
technology, e.g., wavelength continuity constraint in Wavelength
Switched Optical Networks (WSON) [RFC6163]. Such constraints can
lead to the requirement for link by link label availability in path
computation and label assignment.
This document provides efficient encodings of information needed by
the routing and label assignment process in technologies such as
WSON and are potentially applicable to a wider range of
technologies. 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).
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1.1. Node Switching Asymmetry Constraints
For some network elements, the ability of a signal or packet on a
particular input port to reach a particular output port may be
limited. In addition, in some network elements the connectivity
between some input ports and output ports may be fixed, e.g., a
simple multiplexer. To take into account such constraints during
path computation, we model this aspect of a network element via a
connectivity matrix.
The connectivity matrix (ConnectivityMatrix) represents either the
potential connectivity matrix for asymmetric switches or fixed
connectivity for an asymmetric device such as a multiplexer. Note
that this matrix does not represent any particular internal blocking
behavior but indicates which input ports and labels (e.g.,
wavelengths) could possibly be connected to a particular output port
and label pair. Representing internal state dependent blocking for a
node is beyond the scope of this document and, due to its highly
implementation-dependent nature, would most likely not be subject to
standardization in the future. The connectivity matrix is a
conceptual M*m by N*n matrix where M represents the number of input
ports each with m labels and N the number of output ports each with
n labels.
1.2. Non-Local Label Assignment Constraints
If the nature of the equipment involved in a network results in a
requirement for non-local label assignment, we can have constraints
based on limits imposed by the ports themselves and those that are
implied by the current label usage. Note that constraints such as
these only become important when label assignment has a non-local
character. For example, in MPLS an LSR may have a limited range of
labels available for use on an output port, and a set of labels
already in use on that port, and hence unavailable for use. This
information, however, does not need to be shared unless there is
some limitation on the LSR's label swapping ability. For example, if
a TDM node lacks the ability to perform time-slot interchange, or a
WSON lacks the ability to perform wavelength conversion, then the
label assignment process is not local to a single node. In this
case, it may be advantageous to share the label assignment
constraint information for use in path computation.
Port label restrictions (PortLabelRestriction) model the label
restrictions that the network element (node) and link may impose on
a port. These restrictions tell us what labels may or may not be
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used on a link and are intended to be relatively static. More
dynamic information is contained in the information on available
labels. Port label restrictions are specified relative to the port
in general or to a specific connectivity matrix for increased
modeling flexibility. Reference [Switch] gives an example where both
switch and fixed connectivity matrices are used and both types of
constraints occur on the same port.
2. Encoding
This section provides encodings for the information elements defined
in [RWA-Info] 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 protocol (PCEP)
[RFC5440]. Note that the information distributed in [RFC4203] and
[RFC5307] is arranged via the nesting of sub-TLVs within TLVs and
this document defines elements to be used within such constructs.
Specific constructs of sub-TLVs and the nesting of sub-TLVs of the
information element defined by this document will be defined in the
respective protocol enhancement documents.
2.1. Connectivity Matrix Field
The Connectivity Matrix Field represents how input ports are
connected to output ports for network elements. The switch and fixed
connectivity matrices can be compactly represented in terms of a
minimal list of input and output port set pairs that have mutual
connectivity. As described in [Switch], such a minimal list
representation leads naturally to a graph representation for path
computation purposes that involves the fewest additional nodes and
links.
The Connectivity Matrix is uniquely identified only by the
advertising node. There may be more than one Field associated with a
node as a node can partition the switch matrix into several sub-
matrices. This partitioning is primarily to limit the size of any
individual information element used to represent the matrix and to
enable incremental updates. When the matrix is partitioned into sub-
matrices, each sub-matrix will be mutually exclusive to one another
in representing which ports/labels are associated with each sub-
matrix. This implies that two matrices will not have the same {src
port, src label, dst port, dst label}.
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Each sub-matrix is identified via a different Matrix ID which MUST
represent a unique combination of {src port, src label, dst port,
dst label}.
A TLV encoding of this list of link set pairs 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Conn | MatrixID | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Set A #1 |
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Set B #1 :
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Additional Link set pairs as needed |
: to specify connectivity :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where
Connectivity (Conn) (4 bit) is the device type.
0 -- the device is fixed
1 -- the device is switched (e.g., ROADM/OXC)
MatrixID represents the ID of the connectivity matrix and is an 8
bit integer. The value of 0xFF is reserved for use with port label
constraints and should not be used to identify a connectivity matrix.
Link Set A #1 and Link Set B #1 together represent a pair of link
sets. See Section 2.3. for a detail description of the link set
field. There are two permitted combinations for the link set field
parameter "dir" for Link Set A and B pairs:
o Link Set A dir=input, Link Set B dir=output
In this case, the meaning of the pair of link sets A and B in this
case is that any signal that inputs a link in set A can be
potentially switched out of an output link in set B.
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o Link Set A dir=bidirectional, Link Set B dir=bidirectional
The meaning of the pair of link sets A and B in this case is that
any signal that inputs on the links in set A can potentially
output on a link in set B, and any input signal on the links in
set B can potentially output on a link in set A. If link set A is
an input and link set B is an output for a signal, then it
implies that link set A is an output and link set B is an input
for that signal.
See Appendix A for both types of encodings as applied to a ROADM
example.
2.2. Port Label Restriction Field
Port Label Restriction Field tells us what labels may or may not be
used on a link.
The port label restriction can be encoded as follows: More than one
of these fields may be needed to fully specify a complex port
constraint. When more than one of these fields are present, the
resulting restriction is the union of the restrictions expressed in
each field. The use of the reserved value of 0xFF for the MatrixID
indicates that a restriction applies to the port, and not to a
specific connectivity matrix.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MatrixID | RstType | SwitchingCap | Encoding |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Additional Restriction Parameters per Restriction Type |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where:
MatrixID: either is the value in the corresponding Connectivity
Matrix field or takes the value 0xFF to indicate the restriction
applies to the port regardless of any Connectivity Matrix.
RstType (Restriction Type) can take the following values and
meanings:
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0: SIMPLE_LABEL (Simple label selective restriction; See
Section 2.2.1 for details)
1: CHANNEL_COUNT (Channel count restriction; See Section 2.2.2
for details)
2: LABEL_RANGE (Label range device with a movable center label
and width; See Section 2.2.3 for details)
3: SIMPLE_LABEL & CHANNEL_COUNT (Combination of SIMPLE_LABEL
and CHANNEL_COUNT restriction. The accompanying label set and
channel count indicate labels permitted on the port and the
maximum number of channels that can be simultaneously used on
the port; See Section 2.2.4 for details)
4: LINK_LABEL_EXCLUSIVITY (A label may be used at most once
amongst a set of specified ports; See Section 2.2.5 for
details)
SwitchingCap (Switching Capability) is defined in [RFC4203] and
Encoding in [RFC3471]. The combination of these fields defines the
type of labels used in specifying the port label restrictions as
well as the interface type to which these restrictions apply.
Additional Restriction Parameters per RestrictionType field is an
optional field that describes additional restriction parameters for
each RestrictionType pertaining to specific protocols.
2.2.1. SIMPLE_LABEL
In the case of the SIMPLE_LABEL, The format is given by:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MatrixID | RstType = 0 | SwitchingCap | Encoding |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Set Field |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In this case the accompanying label set indicates the labels
permitted on the port/matrix.
See Section 2.6 for the definition of label set.
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2.2.2. CHANNEL_COUNT
In the case of the CHANNEL_COUNT, the format is given by:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MatrixID | RstType = 1 | SwitchingCap | Encoding |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MaxNumChannels |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In this case the accompanying MaxNumChannels indicates the maximum
number of channels (labels) that can be simultaneously used on the
port/matrix.
MaxNumChannels is a 32-bit integer.
2.2.3. LABEL_RANGE
In the case of the LABEL_RANGE, the format is given by:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MatrixID | RstType = 2 | Switching Cap | Encoding |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MaxLabelRange |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Set Field |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
This is a generalization of the waveband device. The MaxLabelRange
indicates the maximum width of the waveband in terms of the channels
spacing given in the Label Set Field. The corresponding label set is
used to indicate the overall tuning range.
MaxLabelRange is a 32-bit integer.
See Section 2.6.2 for the explanation of label range.
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2.2.4. SIMPLE_LABEL & CHANNEL_COUNT
In the case of the SIMPLE_LABEL & CHANNEL_COUNT the format is given
by:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MatrixID | RstType = 3 | SwitchingCap | Encoding |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MaxNumChannels |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Set Field |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In this case the accompanying label set and MaxNumChannels indicate
labels permitted on the port and the maximum number of labels that
can be simultaneously used on the port.
See Section 2.6 for the definition of label set.
2.2.5. Link Label Exclusivity
In the case of the Link Label Exclusivity the format is given by:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MatrixID | RstType = 4 | SwitchingCap | Encoding |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Set Field |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In this case the accompanying link set indicates that a label may be
used at most once among the ports in the link set field. See Section
2.3 for the definition of link set.
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2.3. Link Set Field
We will frequently need to describe properties of groups of links.
To do so efficiently we can make use of a link set concept similar
to the label set concept of [RFC3471]. This Link Set Field is used
in the <ConnectivityMatrix>, which is defined in Section 2.1. The
information carried in a Link Set is defined by:
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 |Dir| Format | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Identifier 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: : :
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Identifier N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Action: 8 bits
0 - Inclusive List
Indicates that one or more link identifiers are included in the Link
Set. Each identifies a separate link that is part of the set.
1 - Inclusive Range
Indicates that the Link Set defines a range of links. It contains
two link identifiers. The first identifier indicates the start of
the range. The second identifier indicates the end of the range. All
links with numeric values between the bounds are considered to be
part of the set. A value of zero in either position indicates that
there is no bound on the corresponding portion of the range. Note
that the Action field can be set to 0x01 (Inclusive Range) only when
identifier for unnumbered link is used.
Dir: Directionality of the Link Set (2 bits)
0 -- bidirectional
1 -- input
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2 -- output
For example, in optical networks we think in terms of unidirectional
as well as bidirectional links. For example, label restrictions or
connectivity may be different for an input port, than for its
"companion" output port if one exists. Note that "interfaces" such
as those discussed in the Interfaces MIB [RFC2863] are assumed to be
bidirectional. This also applies to the links advertised in various
link state routing protocols.
Format: The format of the link identifier (6 bits)
0 -- Link Local Identifier
Indicates that the links in the Link Set are identified by link
local identifiers. All link local identifiers are supplied in the
context of the advertising node.
1 -- Local Interface IPv4 Address
2 -- Local Interface IPv6 Address
Indicates that the links in the Link Set are identified by Local
Interface IP Address.
Others -- Reserved for future use.
Note that all link identifiers in the same list must be of the same
type.
Length: 16 bits
This field indicates the total length in bytes of the Link Set field.
Link Identifier: length is dependent on the link format
The link identifier represents the port which is being described
either for connectivity or label restrictions. This can be the link
local identifier of [RFC4202], GMPLS routing, [RFC4203] GMPLS OSPF
routing, and [RFC5307] IS-IS GMPLS routing. The use of the link
local identifier format can result in more compact encodings when
the assignments are done in a reasonable fashion.
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2.4. Available Labels Field
The Available Labels Field consists of priority flags, and a single
variable length label set 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PRI | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Set Field |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where
PRI (Priority Flags, 8 bits): A bitmap used to indicate which
priorities are being advertised. The bitmap is in ascending order,
with the leftmost bit representing priority level 0 (i.e., the
highest) and the rightmost bit representing priority level 7 (i.e.,
the lowest). A bit MUST be set (1) corresponding to each priority
represented in the sub-TLV, and MUST NOT be set (0) when the
corresponding priority is not represented. If a label is available
at priority M it MUST be advertised available at each priority N <
M. At least one priority level MUST be advertised.
The PRI field indicates the availability of the labels for use in
LSP set up and pre-emption as described in [RFC3209].
When a label is advertised as available for priorities 0, 1, ... M
it may be used by any LSP of priority N <= M. When a label is in use
by an LSP of priority M it may be used by an LSP of priority N < M
if LSP preemption is supported.
When a label was initially advertised as available for priorities,
0, 1, ... M and once a label is used for an LSP at a priority, say N
(N<=M), then this label is advertised as available for 0, ... N-1.
Note that Label Set Field is defined in Section 2.6. See Appendix
A.5. for illustrative examples.
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2.5. Shared Backup Labels Field
The Shared Backup Labels Field consists of priority flags, and
single variable length label set 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PRI | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Set Field |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where
PRI (Priority Flags, 8 bits): A bitmap used to indicate which
priorities are being advertised. The bitmap is in ascending order,
with the leftmost bit representing priority level 0 (i.e., the
highest) and the rightmost bit representing priority level 7 (i.e.,
the lowest). A bit MUST be set (1) corresponding to each priority
represented in the sub-TLV, and MUST NOT be set (0) when the
corresponding priority is not represented. If a label is available
at priority M it MUST be advertised available at each priority N <
M. At least one priority level MUST be advertised.
The same LSP set up and pre-emption rules specified in Section 2.4
apply here.
Note that Label Set Field is defined in Section 2.6. See Appendix
A.5. for illustrative examples.
2.6. Label Set Field
Label Set Field is used within the <AvailableLabels> or the
<SharedBackupLabels>, which is defined in Sections 2.4. and 2.5.,
respectively. It is also used within the <SIMPLE_LABEL>,
<LABEL_RANGE>, <SIMPLE_LABEL> or <CHANNEL_COUNT>, which is defined
in Sections 2.1.1. - 2.1.4., respectively.
The general format for a label set is given below. This format uses
the Action concept from [RFC3471] with an additional Action to
define a "bit map" type of label set. Labels are variable in length.
Action specific fields are defined below.
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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| Num Labels = N | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Base Label |
| . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| (Action specific fields) |
| . . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Action:
0 - Inclusive List
1 - Exclusive List
2 - Inclusive Range
3 - Exclusive Range
4 - Bitmap Set
Num Labels is generally the number of labels. It has a specific
meaning depending on the action value. See Sections 2.6.1 - 2.6.3
for details. Num Labels is a 12 bit integer.
Length is the length in bytes of the entire label set field.
2.6.1. Inclusive/Exclusive Label Lists
In the case of the inclusive/exclusive lists the wavelength set
format is given by:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 or 1 | Num Labels = 2 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label #1 |
| . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label #N |
| . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where:
Label #1 is the first Label to be included/excluded and Label #N is
the last Label to be included/excluded. Num Labels MUST match with
N.
2.6.2. Inclusive/Exclusive Label Ranges
In the case of inclusive/exclusive ranges the label set format is
given by:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|2 or 3 | Num Labels | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Start Label |
| . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| End Label |
| . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note that Start Label is the first Label in the range to be
included/excluded and End Label is the last label in the same range.
Num Labels MUST be two.
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2.6.3. Bitmap Label Set
In the case of Action = 4, the bitmap the label set format is given
by:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 4 | Num Labels | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Base Label |
| . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bit Map Word #1 (Lowest numerical labels) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bit Map Word #N (Highest numerical labels) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where Num Labels in this case tells us the number of labels
represented by the bit map. Each bit in the bit map represents a
particular label with a value of 1/0 indicating whether the label is
in the set or not. Bit position zero represents the lowest label and
corresponds to the base label, while each succeeding bit position
represents the next label logically above the previous.
The size of the bit map is Num Labels bits, but the bit map is
padded out to a full multiple of 32 bits so that the field is a
multiple of four bytes. Bits that do not represent labels (i.e.,
those in positions (Num Labels) and beyond) SHOULD be set to zero
and MUST be ignored.
3. 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
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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].
4. IANA Considerations
This document provides general protocol independent information
encodings. There is no IANA allocation request for the information
elements defined in this document. IANA allocation requests will be
addressed in protocol specific documents based on the encodings
defined here.
5. Acknowledgments
This document was prepared using 2-Word-v2.0.template.dot.
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APPENDIX A: Encoding Examples
Here we give examples of the general encoding extensions applied to
some simple ROADM network elements and links.
A.1. Link Set Field
Suppose that we wish to describe a set of input ports that are have
link local identifiers number 3 through 42. In the link set field we
set the Action = 1 to denote an inclusive range; the Dir = 1 to
denote input links; and, the Format = 0 to denote link local
identifiers. In particular we have:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=1 |0 1|0 0 0 0 0 0| Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #42 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
A.2. Label Set Field
Example:
A 40 channel C-Band DWDM system with 100GHz spacing with lowest
frequency 192.0THz (1561.4nm) and highest frequency 195.9THz
(1530.3nm). These frequencies correspond to n = -11, and n = 28
respectively. Now suppose the following channels are available:
Frequency (THz) n Value bit map position
--------------------------------------------------
192.0 -11 0
192.5 -6 5
193.1 0 11
193.9 8 19
194.0 9 20
195.2 21 32
195.8 27 38
Using the label format defined in [RFC6205], with the Grid value set
to indicate an ITU-T A/2 [G.694.1] DWDM grid, C.S. set to indicate
100GHz this lambda bit map set would then be encoded as follows:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 4 | Num Labels = 40 | Length = 16 bytes |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = -11 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1 0 0 0 0 0 1 0| Not used in 40 Channel system (all zeros) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
To encode this same set as an inclusive list we would have:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0 | Num Labels = 7 | Length = 32 bytes |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = -11 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = -6 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = -0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = 9 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = 21 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. | Reserved | n for lowest frequency = 27 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
A.3. Connectivity Matrix
Example:
Suppose we have a typical 2-degree 40 channel ROADM. In addition to
its two line side ports it has 80 add and 80 drop ports. The picture
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below illustrates how a typical 2-degree ROADM system that works
with bi-directional fiber pairs is a highly asymmetrical system
composed of two unidirectional ROADM subsystems.
(Tributary) Ports #3-#42
Input added to Output dropped from
West Line Output East Line Input
vvvvv ^^^^^
| |||.| | |||.|
+-----| |||.|--------| |||.|------+
| +----------------------+ |
| | | |
Output | | Unidirectional ROADM | | Input
-----------------+ | | +--------------
<=====================| |===================<
-----------------+ +----------------------+ +--------------
| |
Port #1 | | Port #2
(West Line Side) | |(East Line Side)
-----------------+ +----------------------+ +--------------
>=====================| |===================>
-----------------+ | Unidirectional ROADM | +--------------
Input | | | | Output
| | _ | |
| +----------------------+ |
+-----| |||.|--------| |||.|------+
| |||.| | |||.|
vvvvv ^^^^^
(Tributary) Ports #43-#82
Output dropped from Input added to
West Line Input East Line Output
Referring to the figure we see that the Input direction of ports #3-
#42 (add ports) can only connect to the output on port #1. While the
Input side of port #2 (line side) can only connect to the output on
ports #3-#42 (drop) and to the output on port #1 (pass through).
Similarly, the input direction of ports #43-#82 can only connect to
the output on port #2 (line). While the input direction of port #1
can only connect to the output on ports #43-#82 (drop) or port #2
(pass through). We can now represent this potential connectivity
matrix as follows. This representation uses only 29 32-bit words.
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Conn = 1 | MatrixID | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: adds to line
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=1 |0 1|0 0 0 0 0 0| Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #42 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1 0|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: line to drops
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 1|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=1 |1 0|0 0 0 0 0 0| Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #42 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: line to line
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 1|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1 0|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: adds to line
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=1 |0 1|0 0 0 0 0 0| Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #43 |
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #82 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1 0|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: line to drops
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 1|0 0 0 0 0 0|| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=1 |1 0|0 0 0 0 0 0| Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #43 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #82 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: line to line
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 1|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1 0|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
A.4. Connectivity Matrix with Bi-directional Symmetry
If one has the ability to renumber the ports of the previous example
as shown in the next figure then we can take advantage of the bi-
directional symmetry and use bi-directional encoding of the
connectivity matrix. Note that we set dir=bidirectional in the link
set fields.
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(Tributary)
Ports #3-42 Ports #43-82
West Line Output East Line Input
vvvvv ^^^^^
| |||.| | |||.|
+-----| |||.|--------| |||.|------+
| +----------------------+ |
| | | |
Output | | Unidirectional ROADM | | Input
-----------------+ | | +--------------
<=====================| |===================<
-----------------+ +----------------------+ +--------------
| |
Port #1 | | Port #2
(West Line Side) | |(East Line Side)
-----------------+ +----------------------+ +--------------
>=====================| |===================>
-----------------+ | Unidirectional ROADM | +--------------
Input | | | | Output
| | _ | |
| +----------------------+ |
+-----| |||.|--------| |||.|------+
| |||.| | |||.|
vvvvv ^^^^^
Ports #3-#42 Ports #43-82
Output dropped from Input added to
West Line Input East Line Output
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Conn = 1 | MatrixID | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Add/Drops #3-42 to Line side #1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=1 |0 0|0 0 0 0 0 0| Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #42 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 0|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: line #2 to add/drops #43-82
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 0|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=1 |0 0|0 0 0 0 0 0| Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #43 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #82 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: line to line
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 0|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 0|0 0 0 0 0 0| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
A.5. Priority Flags in Available/Shared Backup Labels
If one wants to make a set of labels (indicated by Label Set Field
#1) available only for the highest priority level (Priority Level 0)
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while allowing a set of labels (indicated by Label Set Field #2)
available to all priority levels, the following encoding will
express such need.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1 0 0 0 0 0 0 0| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Set Field #1 |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1 1 1 1 1 1 1 1| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Set Field #2 |
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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6. References
6.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB", RFC 2863, June 2000.
[RFC3209] Awduche, D., et al. "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, December 2001.
[RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Functional Description", RFC 3471,
January 2003.
[G.694.1] ITU-T Recommendation G.694.1, "Spectral grids for WDM
applications: DWDM frequency grid", June, 2002.
[RFC4202] Kompella, K., Ed., and Y. Rekhter, Ed., "Routing
Extensions in Support of Generalized Multi-Protocol Label
Switching (GMPLS)", RFC 4202, October 2005
[RFC4203] Kompella, K., Ed., and Y. Rekhter, Ed., "OSPF Extensions
in Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 4203, October 2005.
[RFC5307] Kompella, K., Ed., and Y. Rekhter, Ed., "IS-IS Extensions
in Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 5307, October 2008.
[RFC6205] T. Otani, Ed. and D. Li, Ed., "Generalized Labels for
Lambda-Switch-Capable (LSC) Label Switching Routers", RFC
6205, March 2011.
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6.2. Informative References
[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) communication Protocol (PCEP) - Version 1",
RFC5440.
[RFC5920] L. Fang, Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, July 2010.
[RFC6163] Y. Lee, G. Bernstein, W. Imajuku, "Framework for GMPLS and
Path Computation Element (PCE) Control of Wavelength
Switched Optical Networks (WSONs)", RFC 6163, April 2011.
[Switch] G. Bernstein, Y. Lee, A. Gavler, J. Martensson, "Modeling
WDM Wavelength Switching Systems for Use in GMPLS and
Automated Path Computation", Journal of Optical
Communications and Networking, vol. 1, June, 2009, pp.
187-195.
[RWA-Info] G. Bernstein, Y. Lee, D. Li, W. Imajuku, "Routing and
Wavelength Assignment Information Model for Wavelength
Switched Optical Networks", work in progress: draft-ietf-
ccamp-rwa-info.
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7. Contributors
Diego Caviglia
Ericsson
Via A. Negrone 1/A 16153
Genoa Italy
Phone: +39 010 600 3736
Email: diego.caviglia@ericsson.com
Anders Gavler
Acreo AB
Electrum 236
SE - 164 40 Kista Sweden
Email: Anders.Gavler@acreo.se
Jonas Martensson
Acreo AB
Electrum 236
SE - 164 40 Kista, Sweden
Email: Jonas.Martensson@acreo.se
Itaru Nishioka
NEC Corp.
1753 Simonumabe, Nakahara-ku, Kawasaki, Kanagawa 211-8666
Japan
Phone: +81 44 396 3287
Email: i-nishioka@cb.jp.nec.com
Rao Rajan
Infinera
Email: rrao@infinera.com
Giovanni Martinelli
CISCO
Email: giomarti@cisco.com
Remi Theillaud
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Marben
remi.theillaud@marben-products.com
Authors' Addresses
Greg M. Bernstein (ed.)
Grotto Networking
Fremont California, USA
Phone: (510) 573-2237
Email: gregb@grotto-networking.com
Young Lee (ed.)
Huawei Technologies
1700 Alma Drive, Suite 100
Plano, TX 75075
USA
Phone: (972) 509-5599 (x2240)
Email: ylee@huawei.com
Dan Li
Huawei Technologies Co., Ltd.
F3-5-B R&D Center, Huawei Base,
Bantian, Longgang District
Shenzhen 518129 P.R.China
Phone: +86-755-28973237
Email: danli@huawei.com
Wataru Imajuku
NTT Network Innovation Labs
1-1 Hikari-no-oka, Yokosuka, Kanagawa
Japan
Phone: +81-(46) 859-4315
Email: imajuku.wataru@lab.ntt.co.jp
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Jianrui Han
Huawei Technologies Co., Ltd.
F3-5-B R&D Center, Huawei Base,
Bantian, Longgang District
Shenzhen 518129 P.R.China
Phone: +86-755-28972916
Email: hanjianrui@huawei.com
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