Network Working Group G. Bernstein (Ed.)
Internet Draft Grotto Networking
Intended status: Informational Y. Lee (Ed.)
Huawei
Moustafa Kattan
Cisco
July 8, 2009
Expires: January 2010
Information Encoding for Impaired Optical Path Validation
draft-bernstein-wson-impairment-encode-01.txt
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Abstract
This document provides an information encoding for the optical
impairment characteristics of optical network elements for use in
path computation and optical path impairment validation. This
encoding is based on ITU-T defined optical network element
characteristics as given in ITU-T recommendation G.680 and related
specifications. This encoding is intentionally compatible with a
previous impairment free optical information encoding used in optical
path computations and wavelength assignment.
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. General Aspects Optical Impairment Information Encoding........3
2.1. Parameter Units and Grouping..............................4
2.2. Frequency Dependence of Parameters........................4
3. Network Element Wide Parameters................................6
3.1. Channel frequency range (GHz, Max, Min)...................6
3.2. Channel insertion loss deviation (dB, Max)................6
3.3. Ripple (dB, Max)..........................................6
3.4. Channel chromatic dispersion (ps/nm, Max, Min)............7
3.5. Differential group delay (ps, Max)........................7
3.6. Polarization dependent loss (dB, Max).....................7
3.7. Reflectance (passive component) (dB, Max).................7
3.8. Reconfigure time/Switching time (ms, Max, Min)............7
3.9. Channel uniformity (dB, Max)..............................7
3.10. Channel addition/removal (steady-state) gain response (dB,
Max, Min)......................................................8
3.11. Transient duration (ms, Max).............................8
3.12. Transient gain increase (dB, Max)........................8
3.13. Transient gain reduction (dB, Max).......................8
3.14. Multichannel gain-change difference (inter-channel gain-
change difference) (dB, Max)...................................8
3.15. Multichannel gain tilt (inter-channel gain-change ratio)(dB,
Max)...........................................................8
4. Per Port Parameters............................................8
4.1. Total input power range (dBm, Max, Min)...................9
4.2. Channel input power range (dBm, Max, Min).................9
4.3. Channel output power range (dBm, Max, Min)...............10
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4.4. Input reflectance (dB, Max) (with amplifiers)............10
4.5. Output reflectance (dB, Max) (with amplifiers)...........10
4.6. Maximum reflectance tolerable at input (dB, Min).........10
4.7. Maximum reflectance tolerable at output (dB, Min)........10
4.8. Maximum total output power (dBm, Max)....................10
5. Port to Port Parameters.......................................10
5.1. Insertion loss (dB, Max, Min)............................11
5.2. Isolation, adjacent channel (dB, Min)....................11
5.3. Isolation, non-adjacent channel (dB, Min)................11
5.4. Channel extinction (dB, Min).............................11
5.5. Channel signal-spontaneous noise figure (dB, Max)........11
5.6. Channel gain (dB, Max, Min)..............................12
6. Security Considerations.......................................12
7. IANA Considerations...........................................12
8. Conclusions...................................................12
9. Acknowledgments...............................................12
10. References...................................................13
10.1. Normative References....................................13
10.2. Informative References..................................14
Author's Addresses...............................................14
Intellectual Property Statement..................................14
Disclaimer of Validity...........................................15
1. Introduction
This document provides an encoding of information used for path
validation in optical networks utilizing approximate computations
based on the information model in [Imp-Info]. The definitions,
characteristics and usage of the optical parameters that form the
model [Imp-Info] and this encoding are based on ITU-T recommendation
G.680 [G.680]. This encoding of the impairment model [Imp-Info] is
intentionally made compatible with the impairment free encode of
reference [RWA-Encode].
2. General Aspects Optical Impairment Information Encoding
The units for the various parameters include GHz, dB, dBm, ms, ps,
and ps/nm. These are typically expressed as floating point numbers.
Due to the measurement limitations inherent in these parameters
single precision floating point, e.g., 32 bit IEEE floating point,
numbers should be sufficient, but we are in the process of conferring
with ITU-T SG15 Q6 on this.
In [Imp-Info] optical impairments were characterized into three
groups: (a) those that apply to the network element as a whole, (b)
those that can vary on a per port basis for a network element, and
(c) those that can vary based on ingress to egress port pairs. In
addition some parameters may also exhibit frequency dependence.
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For realistic optical network elements per port and port-to-port
parameters typically only assume a few different values. For example,
the channel gain of a ROADM is usually specified in terms of input to
drop, add to output, and input to output. This implies that many port
and port-to-port parameters could be efficiently specified, stored
and transported by making use of the Link Set Sub-TLV and
Connectivity Matrix Sub-TLV of reference [RWA-Encode]. In the
following we indicate how these structures could be used. However,
whether such facilities are used is dependent upon the specific
protocol context, e.g., OSPF, IS-IS, etc.
2.1. Parameter Units and Grouping
The encoding discussed here is assumed to occur within a type-length-
value (TLV) structure. In such a structure the type and length fields
form a "header" of sorts. From the type field we would infer the
following:
o Units of the parameter, i.e., dB, dBm, GHz, ps, etc...
o The grouping of the parameters. For some parameters such as
chromatic dispersion, maximum and minimum values are always
specified.
o Whether the parameter may exhibit frequency dependence. Encoding
of frequency dependent parameters is discussed in the next
section.
2.2. Frequency Dependence of Parameters
Some parameters may exhibit a frequency dependence that needs to be
accounted for over the frequency/wavelength of the system. We provide
here an extensible encoding of this dependence that can take into
account general purpose interpolation methods such as linear
interpolation, cubic splines, etc... as well as application specific
interpolation methods such as the 3-term and 5-term Sellmeier
formulas of Appendix A of reference [G.650.1]. The following
considerations are used in the encoding of frequency dependency:
1. Each parameter in a group of parameters will have its own
interpolation data. We know from the "type" of the parameter how
many sub-parameters are in this group.
2. Interpolation data may be broken into subranges of validity for a
formula with particular interpolation coefficients.
3. The type of interpolation to be used over the sub-ranges must be
specified
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4. We assume that each sub-range will make use of the same type of
interpolation formula (TBD if this is condition is too limiting).
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Interpolation| Num Ranges | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Start Wavelength (first range) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: Range 1, sub-parameter 1 :
+ Interpolation type particular data +
|-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-:
: Interpolation data for :
+ other sub-parameters +
|-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-:
| Start Wavelength (next range) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: Range 2, sub-parameter 1 :
+ Interpolation type particular data +
|-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-:
: More ranges if needed :
: :
|-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-|
| End Wavelength (for last range) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where
"Interpolation" is the type of interpolation to be used across the
range.
0 Piecewise Constant. In this form of interpolation a single
value of the parameter is used across each sub-range.
1 Linear Interpolation. In this form of interpolation two values
of the parameter are given corresponding to the value at each
end of the frequency sub-range. Linear interpolation is used to
obtain the parameter values for frequencies between the sub-
range limits.
Others Interpolation type are FFS.
"Num Ranges" is an integer that gives the number of sub-ranges for
the interpolation.
Each interpolation specific parameter block is preceded by a "start
wavelength" which is used to indicate the beginning of that range.
The following ranges "start wavelength" will be used as the ending
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wavelength for that range, except for the last range which requires
an explicit "end wavelength".
In the case of "no interpolation" the sub-parameter value is assumed
to be valid over the entire sub-range and no additional interpolation
related parameters or coefficients are needed.
[To be completed: examples of piecewise constant interpolation with a
particular frequency dependent impairment parameter.]
3. Network Element Wide Parameters
IEEE 754-2008 format 32 bit floating point numbers are used for the
following parameter values. Units are specified with each parameter.
Each of the following individual parameters would need to be
explicitly identified via some kind of code point mechanism.
3.1. Channel frequency range (GHz, Max, Min)
The channel frequency range is expressed in GHz.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min frequency in GHz IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max frequency in GHz IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
From the perspective of a control plane making use of standard grid
spacing and given the encoding of lambda of [Otani] it is not clear
whether this parameter is needed. Use is FFS/Liaison.
3.2. Channel insertion loss deviation (dB, Max)
A 32 bit IEEE floating point number. This parameter may be frequency
dependent.
3.3. Ripple (dB, Max)
A 32 bit IEEE floating point number.
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3.4. Channel chromatic dispersion (ps/nm, Max, Min)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min dispersion in ps/nm IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max dispersion in ps/nm IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
These parameters generally exhibit frequency dependence.
3.5. Differential group delay (ps, Max)
A 32 bit IEEE floating point number.
3.6. Polarization dependent loss (dB, Max)
A 32 bit IEEE floating point number.
3.7. Reflectance (passive component) (dB, Max)
A 32 bit IEEE floating point number.
3.8. Reconfigure time/Switching time (ms, Max, Min)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min Reconfigure time in ms IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max Reconfigure time in ms IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3.9. Channel uniformity (dB, Max)
A 32 bit IEEE floating point number.
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3.10. Channel addition/removal (steady-state) gain response (dB, Max,
Min)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min gain response in dB IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max gain response in dB IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3.11. Transient duration (ms, Max)
A 32 bit IEEE floating point number.
3.12. Transient gain increase (dB, Max)
A 32 bit IEEE floating point number.
3.13. Transient gain reduction (dB, Max)
A 32 bit IEEE floating point number.
3.14. Multichannel gain-change difference (inter-channel gain-change
difference) (dB, Max)
A 32 bit IEEE floating point number.
3.15. Multichannel gain tilt (inter-channel gain-change ratio)(dB, Max)
A 32 bit IEEE floating point number.
4. Per Port Parameters
Per port parameters fit well within the category of link parameters
that are typically disseminated by a link state protocol. However,
since many optical ports on a device tend to have the same parameters
grouping these parameters together for conveyance makes sense and can
aid in interpretation. For example, in a high channel count ROADM
with many add and drop ports the characteristics of all the add ports
would tend to be similar to each other, and likewise for the drop
ports, but these would tend to be different from each other and the
trunk (or through) ports. Hence we propose an optional simple
grouping mechanism based on grouping common per port parameters along
with a Link Set sub-TLV [RWA-Encode] that specifies the set of links
that share the same port parameters.
For example:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Set TLV |
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Port Parameter TLV #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Port Parameter TLV #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Port Parameter TLV #N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Each of the following individual parameters would need to be
explicitly identified via some kind of code point mechanism.
4.1. Total input power range (dBm, Max, Min)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min power in dBm IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max power in dBm IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.2. Channel input power range (dBm, Max, Min)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min power in dBm IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max power in dBm IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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4.3. Channel output power range (dBm, Max, Min)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min power in dBm IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max power in dBm IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.4. Input reflectance (dB, Max) (with amplifiers)
A 32 bit IEEE floating point number.
4.5. Output reflectance (dB, Max) (with amplifiers)
A 32 bit IEEE floating point number.
4.6. Maximum reflectance tolerable at input (dB, Min)
A 32 bit IEEE floating point number.
4.7. Maximum reflectance tolerable at output (dB, Min)
A 32 bit IEEE floating point number.
4.8. Maximum total output power (dBm, Max)
A 32 bit IEEE floating point number.
5. Port to Port Parameters
To specify port-to-port parameters we need to indicate the port pair
that they apply to. Since many port pairs have the same parameter
values and there maybe a great number of possible port pairs, it can
be worth while to group port pairs with the same parameter values in
our encoding. In addition, this is typically how these parameters are
specified. For example, the specification data for a simple ROADM may
give the insertion loss for the "through to drop ports" as a single
parameter, along with a separate insertion loss parameter for the
"add to through ports".
In [RWA-Encode] the Connectivity Matrix sub-TLV is essentially a
compact listing of ingress-egress port pairs. Hence we can use this
structure to communicate common port-to-port parameters for a set of
ingress-egress pairs.
For example:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Connectivity Matrix Sub-TLV |
| (list of ingress-egress port pairs with common parameters) |
: : :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Port-Port Parameter TLV #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Port-Port Parameter TLV #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Port-Port Parameter TLV #N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Each of the following individual parameters would need to be
explicitly identified via some kind of code point mechanism.
5.1. Insertion loss (dB, Max, Min)
TBD if this parameter changes with frequency.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min Insertion loss in dB IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max Insertion loss in dB IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
5.2. Isolation, adjacent channel (dB, Min)
A 32 bit IEEE floating point number.
5.3. Isolation, non-adjacent channel (dB, Min)
A 32 bit IEEE floating point number.
5.4. Channel extinction (dB, Min)
A 32 bit IEEE floating point number. This parameter may change with
frequency.
5.5. Channel signal-spontaneous noise figure (dB, Max)
A 32 bit IEEE floating point number. This parameter may change with
frequency.
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5.6. Channel gain (dB, Max, Min)
This parameter may exhibit frequency dependence.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min Channel gain in dB IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max Channel gain in dB IEEE float |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
6. Security Considerations
This document defines an encoding for an information model describing
impairments in optical networks. If such a encoding is put into use
within a network it will by its nature contain details of the
physical characteristics of an optical network. Such information
would need to be protected from intentional or unintentional
disclosure.
7. IANA Considerations
This draft does not currently require any consideration from IANA.
8. Conclusions
The state of standardization of optical device characteristics has
matured from when initial IETF work concerning optical impairments
was investigated in [RFC4054]. Relatively recent ITU-T
recommendations provide a standardized based of optical
characteristic definitions and parameters that control plane
technologies such as GMPLS and PCE can make use of in performing
optical path validation. The enclosed information model shows how
readily such ITU-T optical work can be utilized within the control
plane.
9. Acknowledgments
This document was prepared using 2-Word-v2.0.template.dot.
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10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[G.650.1] ITU-T Recommendation G.650.1, Definitions and test methods
for linear, deterministic attributes of single-mode fibre
and cable, June 2004.
[G.661] ITU-T Recommendation G.661, Definition and test methods for
the relevant generic parameters of optical amplifier
devices and subsystems, March 2006.
[G.671] ITU-T Recommendation G.671, Transmission characteristics of
optical components and subsystems, January 2005.
[G.680] ITU-T Recommendation G.680, Physical transfer functions of
optical network elements, July 2007.
[Imp-Frame] G. Bernstein, Y. Lee, D. Li, G. Martinelli, "A Framework
for the Control and Measurement of Wavelength Switched
Optical Networks (WSON) with Impairments", Work in
Progress, draft-bernstein-ccamp-wson-impairments-05.txt
[Imp-Info]Y. Lee, G. Bernstein, M. Kattan, "Information Model for
Impaired Optical Path Validation", Work in Progress, draft-
bernstein-wson-impairment-info-02.txt.
[Otani] T. Otani, H. Guo, K. Miyazaki, D. Caviglia, "Generalized
Labels for G.694 Lambda-Switching Capable Label Switching
Routers", work in progress, draft-ietf-ccamp-gmpls-g-694-
lambda-labels.
[RFC4054] Strand, J., Ed., and A. Chiu, Ed., "Impairments and Other
Constraints on Optical Layer Routing", RFC 4054, May 2005.
[RWA-Info] Y. Lee, G. Bernstein, D. Li, W. Imajuku, "Routing and
Wavelength Assignment Information Model for Wavelength
Switched Optical Networks", Work in Progress, draft-ietf-
ccamp-rwa-info.
[RWA-Encode]G. Bernstein, Y. Lee, D. Li, W. Imajuku, "Routing and
Wavelength Assignment Information Encoding for Wavelength
Switched Optical Networks" Work in progress, draft-ietf-
ccamp-rwa-wson-encode.
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10.2. Informative References
Author's Addresses
Greg Bernstein
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
Moustafa Kattan
Cisco Systems,
Dubai Internet City # 10,
Dubai, UAE
Phone (408)527-5101
Email:mkattan@cisco.com
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