Network Working Group G. Bernstein (Ed.) Internet Draft Grotto Networking Intended status: Informational Y. Lee (Ed.) Huawei Xian Zhang Huawei February 21, 2013 Expires: August 2013 Information Encoding for Impaired Optical Path Validation draft-bernstein-wson-impairment-encode-02.txt 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. 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 Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on August 21, 2013. Bernstein Expires August 21, 2013 [Page 1] Internet-Draft Optical Impairment Info Model February 2013 Copyright Notice Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. 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 [RFC2119]. 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. Table of Contents 1. Introduction...................................................3 2. General Aspects Optical Impairment Information Encoding........4 2.1. Parameter Units and Grouping..............................4 2.2. Frequency Dependence of Parameters........................4 3. Network Element Wide Parameters................................7 3.1. Channel frequency range (GHz, Max, Min)...................7 3.2. Channel insertion loss deviation (dB, Max)................7 3.3. Ripple (dB, Max)..........................................7 3.4. Channel chromatic dispersion (ps/nm, Max, Min)............8 3.5. Differential group delay (ps, Max)........................8 3.6. Polarization dependent loss (dB, Max).....................8 3.7. Reflectance (passive component) (dB, Max).................8 3.8. Reconfigure time/Switching time (ms, Max, Min)............8 Bernstein Expires August 21, 2013 [Page 2] Internet-Draft Optical Impairment Info Model February 2013 3.9. Channel uniformity (dB, Max)..............................8 3.10. Channel addition/removal (steady-state) gain response (dB, Max, Min)......................................................9 3.11. Transient duration (ms, Max).............................9 3.12. Transient gain increase (dB, Max)........................9 3.13. Transient gain reduction (dB, Max).......................9 3.14. Multichannel gain-change difference (inter-channel gain- change difference) (dB, Max)...................................9 3.15. Multichannel gain tilt (inter-channel gain-change ratio)(dB, Max)................................................9 4. Per Port Parameters............................................9 4.1. Total input power range (dBm, Max, Min)..................10 4.2. Channel input power range (dBm, Max, Min)................10 4.3. Channel output power range (dBm, Max, Min)...............11 4.4. Input reflectance (dB, Max) (with amplifiers)............11 4.5. Output reflectance (dB, Max) (with amplifiers)...........11 4.6. Maximum reflectance tolerable at input (dB, Min).........11 4.7. Maximum reflectance tolerable at output (dB, Min)........11 4.8. Maximum total output power (dBm, Max)....................11 5. Port to Port Parameters.......................................11 5.1. Insertion loss (dB, Max, Min)............................12 5.2. Isolation, adjacent channel (dB, Min)....................12 5.3. Isolation, non-adjacent channel (dB, Min)................12 5.4. Channel extinction (dB, Min).............................12 5.5. Channel signal-spontaneous noise figure (dB, Max)........12 5.6. Channel gain (dB, Max, Min)..............................13 6. Security Considerations.......................................13 7. IANA Considerations...........................................13 8. Conclusions...................................................13 9. Acknowledgments...............................................13 10. References...................................................14 10.1. Normative References....................................14 10.2. Informative References..................................15 Author's Addresses...............................................15 Intellectual Property Statement........Error! Bookmark not defined. Disclaimer of Validity.................Error! Bookmark not defined. 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]. Bernstein Expires August 21, 2013 [Page 3] Internet-Draft Optical Impairment Info Model February 2013 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. 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 Bernstein Expires August 21, 2013 [Page 4] Internet-Draft Optical Impairment Info Model February 2013 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 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). Bernstein Expires August 21, 2013 [Page 5] Internet-Draft Optical Impairment Info Model February 2013 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 wavelength for that range, except for the last range which requires an explicit "end wavelength". Bernstein Expires August 21, 2013 [Page 6] Internet-Draft Optical Impairment Info Model February 2013 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. Bernstein Expires August 21, 2013 [Page 7] Internet-Draft Optical Impairment Info Model February 2013 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. Bernstein Expires August 21, 2013 [Page 8] Internet-Draft Optical Impairment Info Model February 2013 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: Bernstein Expires August 21, 2013 [Page 9] Internet-Draft Optical Impairment Info Model February 2013 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Bernstein Expires August 21, 2013 [Page 10] Internet-Draft Optical Impairment Info Model February 2013 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: Bernstein Expires August 21, 2013 [Page 11] Internet-Draft Optical Impairment Info Model February 2013 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. Bernstein Expires August 21, 2013 [Page 12] Internet-Draft Optical Impairment Info Model February 2013 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. Bernstein Expires August 21, 2013 [Page 13] Internet-Draft Optical Impairment Info Model February 2013 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. [RFC6566] G. Bernstein, Y. Lee, D. Li, G. Martinelli, "A Framework for the Control and Measurement of Wavelength Switched Optical Networks (WSON) with Impairments", RFC 6566, March 2012. [Imp-Info] Y. Lee, G. Bernstein, M. Kattan, "Information Model for Impaired Optical Path Validation", Work in Progress, draft-bernstein-wson-impairment-info [RFC6205] T. Otani, H. Guo, K. Miyazaki, D. Caviglia, "GeneralizedLabels for G.694 Lambda-Switching Capable Label Switching Routers", RFC 6205, March 2011. [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 Bernstein Expires August 21, 2013 [Page 14] Internet-Draft Optical Impairment Info Model February 2013 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 Xian Zhang Huawei Technologies F3-5-B R&D Center, Huawei Base Bantian, Longgang District Shenzhen 518129 P.R.China Phone: +86-755-28972913 Email: zhang.xian@huawei.com Intellectual Property Statement The IETF Trust takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in any IETF Document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Copies of Intellectual Property disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr Bernstein Expires August 21, 2013 [Page 15] Internet-Draft Optical Impairment Info Model February 2013 The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement any standard or specification contained in an IETF Document. Please address the information to the IETF at ietf-ipr@ietf.org. Disclaimer of Validity All IETF Documents and the information contained therein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION THEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Bernstein Expires August 21, 2013 [Page 16]