One document matched: draft-bernstein-ccamp-wson-info-00.txt
Network Working Group Greg Bernstein
Internet Draft Grotto Networking
Intended status: Standards Track Young Lee
Expires: April 2008 Dan Li
Huawei
October 30, 2007
Routing and Wavelength Assignment Information for Wavelength
Switched Optical Networks
draft-bernstein-ccamp-wson-info-00.txt
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Copyright Notice
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Copyright (C) The IETF Trust (2007).
Abstract
This memo provides compact encodings for information needed for path
computation and wavelength assignment in wavelength switched optical
networks. Such encodings can be used in extensions to Generalized
Multi-Protocol Label Switching (GMPLS) routing for control of
wavelength switched optical networks (WSON).
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
2. Terminology....................................................3
3. Generic Information............................................3
3.1. Wavelength Information Encoding...........................3
3.2. Link Sets.................................................4
3.3. Wavelength Sets...........................................6
3.3.1. Inclusive/Exclusive Wavelength Lists.................7
3.3.2. Inclusive/Exclusive Wavelength Ranges................7
3.3.3. Bitmap Wavelength Set................................8
4. WSON Information for Routing and Wavelength Assignment.........9
4.1. Connectivity Matrix......................................10
4.2. Port Wavelength Restrictions.............................11
4.3. WDM Link Characterization................................13
4.4. Laser Transmitter Range..................................13
4.5. Wavelength Converter Characterization....................13
4.6. Wavelength Availability..................................13
5. Security Considerations.......................................14
6. IANA Considerations...........................................14
7. Acknowledgments...............................................14
8. References....................................................15
8.1. Normative References.....................................15
8.2. Informative References...................................15
9. Contributors..................................................16
Author's Addresses...............................................16
Intellectual Property Statement..................................16
Disclaimer of Validity...........................................17
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1. Introduction
This document provides efficient encodings of information needed by
the routing and wavelength assignment (RWA) process in wavelength
switched optical networks (WSONs). Such encodings can be applied to
GMPLS IGP extensions to accommodate this WSON/RWA information. In
addition these encodings could be used by other mechanisms to convey
this same information to a path computation element (PCE). Note since
these encodings are relatively efficient they can provide more
accurate analysis of the control plane communications/processing load
for WSONs looking to utilize a GMPLS control plane.
2. Terminology
CWDM: Coarse Wavelength Division Multiplexing.
DWDM: Dense Wavelength Division Multiplexing.
FOADM: Fixed Optical Add/Drop Multiplexer.
ROADM: Reconfigurable Optical Add/Drop Multiplexer. A reduced port
count wavelength selective switching element featuring ingress and
egress line side ports as well as add/drop side ports.
RWA: Routing and Wavelength Assignment.
Wavelength Conversion/Converters: The process of converting an
information bearing optical signal centered at a given wavelength to
one with "equivalent" content centered at a different wavelength.
Wavelength conversion can be implemented via an optical-electronic-
optical (OEO) process or via a strictly optical process.
WDM: Wavelength Division Multiplexing.
Wavelength Switched Optical Networks (WSON): WDM based optical
networks in which switching is performed selectively based on the
center wavelength of an optical signal.
3. Generic Information
The following encodings have multiple uses in specifying WSON
information.
3.1. Wavelength Information Encoding
This document makes frequent use of the lambda label format defined
in [Otani] shown 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. |S| Reserved | n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where
Grid is used to indicate which ITU-T grid specification is being
used.
C.S. = Channel spacing used in a DWDM system, i.e., with a ITU-T
G.694.1 grid.
S = sign of the offset from the center frequency of 193.1THz for the
ITU-T 6.694.1 grid.
n = Used to specify the frequency as 193.1THz +/- n*(channel spacing)
where the + or - is chosen based on the sign (S) bit.
3.2. Link Sets
We will frequently want to describe properties of links. To do so
efficiently we can make use of a link set concept similar to the
label set concept of [RFC3471]. All links will be denoted by their
local link identifier as defined an used in[RFC4202, RFC4203,
RFC4205].
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 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Identifier 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: : :
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Identifier N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Action: 8 bits
0 - Inclusive List
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Indicates that the object/TLV contains one or more link elements
that are included in the Link Set.
1 - Exclusive List
Indicates that the object/TLV contains one or more link elements that
are excluded from the Link Set.
2 - Inclusive Range
Indicates that the object/TLV contains a range of links. The
object/TLV contains two link elements. The first element indicates
the start of the range. The second element indicates the end of the
range. A value of zero indicates that there is no bound on the
corresponding portion of the range.
3 - Exclusive Range
Indicates that the object/TLV contains a range of links that are
excluded from the Link Set. The object/TLV contains two link
elements. The first element indicates the start of the range. The
second element indicates the end of the range. A value of zero
indicates that there is no bound on the corresponding portion of the
range.
Dir: Directionality of the Link Set (2 bits)
0 -- bidirectional
1 -- ingress
2 -- egress
In optical networks we think in terms of unidirectional as well as
bidirectional links. For example wavelength restrictions or
connectivity may be much different for an ingress port, than for its
"companion" egress port if it has one. Note that "interfaces" such as
discussed in the Interfaces MIB are assumed bidirectional, as well as
the links of various link state IGPs.
Format: The format of the link identifier (6 bits)
0 -- Link Local Identifier
Others TBD.
Reserved: 16 bits
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This field is reserved. It MUST be set to zero on transmission and
MUST be ignored on receipt.
Link Identifier:
The link identifier represents the port which is being described
either for connectivity or wavelength restrictions. This can be the
link local identifier of [RFC4202], GMPLS routing, [RFC4203] GMPLS
OSPF routing, and [RFC4205] IS-IS GMPLS routing. The use of the link
local identifier format can result in more compact WSON encodings
when the assignments are done in a reasonable fashion.
3.3. Wavelength Sets
Wavelength sets come up frequently in WSONs to describe the range of
a laser transmitter, the wavelength restrictions on ROADM ports, or
the availability of wavelengths on a DWDM link. The general format
for a wavelength 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. Note that the second 32 bit field is a lambda
label in the previously defined format. This provides important
information on the WDM grid type and channel spacing that will be
used in the compact encodings listed.
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 | Num Wavelengths |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. |S| Reserved | n for lowest frequency |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Additional fields as necessary per action |
|
Action:
0 - Inclusive List
1 - Exclusive List
2 - Inclusive Range
3 - Exclusive Range
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4 - Bitmap Set
Note that the "Application" field will be used initially in the
specification of ROADM/OXC wavelength restrictions, but may be used
in other contexts as well.
3.3.1. Inclusive/Exclusive Wavelength Lists
In the case of the inclusive/exclusive lists the wavelength 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Action=0 or 1 | Reserved | Num Wavelengths |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. |S| Reserved | n for lowest frequency |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| n2 | n3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| nm | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where Num Wavelengths tells us the number of wavelength in this
inclusive or exclusive list this does not include the initial
wavelength in the list hence if the number of wavelengths is odd then
zero padding of the last half word is required.
3.3.2. Inclusive/Exclusive Wavelength Ranges
In the case of inclusive/exclusive ranges the wavelength 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Action=2 or 3 | Reserved | Num Wavelengths |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. |S| Reserved | n for lowest frequency |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In this case Num Wavelengths specifies the number of wavelengths in
the range starting at the given wavelength and incrementing the Num
Wavelengths number of channel spacing up in frequency (regardless of
the value of the sign bit).
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3.3.3. Bitmap Wavelength Set
In the case of Action = the bitmap the wavelength 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action = 4 | Reserved | Num Wavelengths |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. |S| Reserved | n for lowest frequency |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bit Map Word #1 (Lowest frequency channels) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bit Map Word #N (Highest frequency channels) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where Num Wavelengths in this case tells us the number of wavelengths
represented by the bit map which is required to be ceiling[(Num
Wavelengths)/32]. Each bit in the bit map represents a particular
frequency with a value of 1/0 indicating whether the frequency is in
the set or not. Bit position zero represents the lowest frequency,
while each succeeding bit position represents the next frequency a
channel spacing (C.S.) above the previous.
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
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With the Grid value set to indicate an ITU-T G.694.1 DWDM grid, C.S.
set to indicate 100GHz, and with S (sign) set to indicate negative
this lambda bit map set would then 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action = 4 | Reserved | Num Wavelengths = 40 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S. |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) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4. WSON Information for Routing and Wavelength Assignment
From [WSON-Frame] the following WSON information needs to be conveyed
via GMPLS routing or some other mechanism.
Information Static/Dynamic Node/Link
------------------------------------------------------------------
Connectivity matrix Static Node
Per port wavelength restrictions Static Node(1)
WDM link (fiber) lambda ranges Static(4) Link
WDM link channel spacing Static(4) Link
Laser Transmitter range Static(4) Link(2)
Wavelength conversion capabilities Static(3),(4) Node
Wavelength Availability Dynamic(4) Link
Notes:
1. These are the per port wavelength restrictions of an optical
device such as a ROADM and are independent of any optical
constraints imposed by a fiber link.
2. This could also be viewed as a node capability.
3. This could be dynamic in the case of a limited pool of converters
where the number available can change with connection
establishment. Note we may want to include regeneration
capabilities here since OEO converters are also regenerators.
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4. Not necessarily needed in the case of distributed wavelength
assignment via signaling.
See [WSON-Frame] for more details on these types of WSON information
and their use.
4.1. Connectivity Matrix
The potential connectivity matrix for asymmetric switches (e.g.
ROADMs and such) and the connectivity matrix for asymmetric fixed
devices can be represented by a matrix A where Amn = 0 or 1,
depending upon whether a wavelength on ingress port m can be
connected to egress port n.
This can be compactly represented link sets 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Connectivity | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ingress Link Set #1 |
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Egress Link Set #1
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Additional Link set pairs as needed |
: to specify connectivity :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where Connectivity = 0 if the device is fixed
1 if the device is reconfigurable (ROADM/OXC)
Example:
Suppose we have a 2-degree 40 channel ROADM. In addition to its line
side ingress and egress ports it has 40 add and 40 drop ports. Assume
that the line side ingress port is given the link local identifier
#1, the 40 add ports are given the link local identifiers #2-#41, the
egress line side port is given the link local identifier #42, and the
40 drop ports are given the link local identifiers #43-#82. Then to
express the connectivity of this ROADM, i.e., that the line side
ingress can connect to any drop port or the line side egress, and
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that the add ports can only connect to the line side egress (but not
the drop ports) we 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Conn = 1 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: Ingress Link Set A
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=2 |0 1|0 0 0 0 0 0|Reserved(Note:inclusive range) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #41 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: Egress Link Set A
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |1 0|0 0 0 0 0 0|Reserved (Note:inclusive list) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #42 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: Ingress Link Set B line side ingress
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=0 |0 1|0 0 0 0 0 0|Reserved (Note:inclusive list) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Note: Egress Link Set #B drop ports
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action=2 |1 0|0 0 0 0 0 0|Reserved(Note: inclusive range)|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #43 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Local Identifier = #82 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
For a total of eleven 32 bit words.
4.2. Port Wavelength Restrictions
An optical switching device can have the following wavelength
restrictions:
o Multiple wavelengths, full range port
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o Single wavelength, full range port
o Single wavelength, fixed lambda port
o Multiple wavelengths, reduced range port (like wave band
switching)
This can be encoded as a doublet of link set and wavelength set
information:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|M| Mapping | Multiplier | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Set |
| .. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Wavelength Set |
| .. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where the "M" bit indicates whether the set of ports are single
wavelength M = 0, or multi-wavelength, M = 1, ports.
The "Mapping" tells us how the wavelengths in the wavelength set get
assigned to the links in the link set.
Mapping = 0: One to Many
Each link in the link set can take any of the values in the
wavelength set. This is applicable to both single channel and multi-
channel ports.
Mapping = 1: One to One
Links are assigned a single wavelength with respect to the order of
links and wavelengths in their respective sets. This is applicable
only to single channel ports (M=0).
Mapping = 2: One to One via ranges and increments
For single channel ports (M=0) where the wavelength is specified via
a range then the frequency assigned to a port is given by
Freq = freq_low + k*(Multiplier + 1)*(C.S.)
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Where k is the ordinal of the link in the link set starting from
zero, C.S. the channel spacing, and freq_low is the lowest frequency
in the wavelength range. Such a formulation gives a compact way to
represent ROADMs with colored drop ports with a regular frequency
plan.
Note that the link set has an indication of whether these constraints
apply to ingress, egress or bidirectionally to the ports.
4.3. WDM Link Characterization
This has the same form as the port wavelength restrictions of a
device, hence can be encoded in the same way as was done in section
4.2.
4.4. Laser Transmitter Range
The tuning range of a laser transmitter can be represented via the
wavelength set mechanism of section 3.3.
4.5. Wavelength Converter Characterization
An OEO based wavelength converter can be characterized by an input
wavelength set and an output wavelength set. In addition we'd want
to know constraints on the signal formats and rates accommodated by
the converter.
Hence we'd have something like:
<Wavelength Converter> := <Input Wavelength Set>, <Output Wavelength
Set>, <Signal Types supported>, <Bit Rate Range Supported>
4.6. Wavelength Availability
The availability of a specific wavelength on a WDM link is key
dynamic information that is required by the RWA process. This
information needs to be accurate; luckily it can also be represented
quite compactly via the wavelength set encodings of section 3.3.
For example a 120 channel system, utilizing the bit map wavelength
set encoding would only require four bit map words in addition to the
two general words in the encoding to fully characterize wavelength
availability. Note that a subset of the total system range could be
sent representing only those lambdas whose availabilities have
changed resulting in very efficient use of control plane bandwidth.
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5. Security Considerations
This document has no requirement for a change to the security models
within GMPLS and associated protocols. That is the OSPF-TE, RSVP-TE,
and PCEP security models could be operated unchanged.
6. IANA Considerations
TBD. Once finalized in our approach we will need identifiers for such
things and modulation types, modulation parameters, wavelength
assignment methods, etc...
7. Acknowledgments
This document was prepared using 2-Word-v2.0.template.dot.
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8. References
8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[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.
8.2. Informative References
[Otani] T. Otani, H. Guo, K. Miyazaki, D. Caviglia, "Generalized
Labels of Lambda-Switching Capable Label Switching Routers
(LSR)", work in progress: draft-otani-ccamp-gmpls-lambda-
labels-00.txt, June 2007.
[G.694.1] ITU-T Recommendation G.694.1, Spectral grids for WDM
applications: DWDM frequency grid, June 2002.
[G.694.2] ITU-T Recommendation G.694.2, Spectral grids for WDM
applications: CWDM wavelength grid, December 2003.
[RFC4205] Kompella, K., Ed., and Y. Rekhter, Ed., "Intermediate
System to Intermediate System (IS-IS) Extensions in Support
of Generalized Multi-Protocol Label Switching (GMPLS)", RFC
4205, October 2005.
[WSON-Frame] G. Bernstein, Y. Lee, W. Imajuku, "Framework for GMPLS
and PCE Control of Wavelength Switched Optical Networks",
work in progress: draft-bernstein-ccamp-wavelength-
switched-01.txt, September 2007.
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9. Contributors
Author's Addresses
Greg Bernstein (ed.)
Grotto Networking
Fremont, CA, 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
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Copyright (C) The IETF Trust (2007).
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Acknowledgment
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Bernstein and Lee Expires April 30, 2008 [Page 17]
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