Internet Engineering Task Force M. Kattan, Ed. Internet-Draft G. Martinelli Intended status: Informational D. Bianchi Expires: April 4, 2011 Cisco N. Ibrahim MOT/OGERO March 2011 WSON Wavelenght Property Information draft-kattan-wson-property-01 Abstract Wavelength Switched Optical Network will extend GMPLS protocols to to manage wavelength across DWDM optical networks. In many situations the control plane needs to know additional information regarding wavelengths. The current proposal identify a way to carry some property information along with wavelength information. Control plane can leverage the knowledge of such properties during its operations. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on April 4, 2011. Copyright Notice Copyright (c) 2010 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 Kattan, et al. Expires April 4, 2011 [Page 1] Internet-Draft Abbreviated Title October 2010 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. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Requirements Language . . . . . . . . . . . . . . . . . . . 3 2. Scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Lambda Properties Definitions . . . . . . . . . . . . . . . . . 5 4. Lambda Properties Encoding . . . . . . . . . . . . . . . . . . 6 4.1. OSPF Extensions . . . . . . . . . . . . . . . . . . . . . . 6 4.2. RSVP Extensions . . . . . . . . . . . . . . . . . . . . . . 7 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 8 7. Security Considerations . . . . . . . . . . . . . . . . . . . . 8 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 8.1. Normative References . . . . . . . . . . . . . . . . . . . 8 8.2. Informative References . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 9 Kattan, et al. Expires April 4, 2011 [Page 2] Internet-Draft Abbreviated Title October 2010 1. Introduction One the current Generalized MPLS (GMPLS) evolutions is toward the Wavelength Switched Optical Networks (WSON) as described in [I-D.ietf-ccamp-rwa-wson-framework]. A related work is defined within [I-D.ietf-ccamp-gmpls-g-694-lambda-labels] defining the GMPLS label in a format suitable for Lambda Switched Capable (LSC equipments). Todays WSON networks are implemented through DWDM technologies and they treats all light paths as equal regardless of the type of data, bandwidth and mission criticality of the traffic it is carrying. This draft suggests the introduction of some properties like prioritizing light paths for scenarios such as restoration, fiber congestion and resource contention. This could be achieved in assigning properties information to each light path. Following sections will describe some scenarios where such information will be useful. How those information are assigned is out of the scope of this draft. 1.1. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119]. 2. Scenarios The following list identify several scenarios occurring in operating WSON networks where some wavelength information will help. Note that this scenarios are triggered by the availability of new reconfigurable equipments allowing new level of flexibility within DWDM networks. Example of this hardware would be multi-degree Reconfigurable Optical Add Drop Multiplexers or ROADMs to support mesh DWDM networks. Fiber 1 is an example of a meshed DWDM network where multiple light path are being set up to and from node C. Kattan, et al. Expires April 4, 2011 [Page 3] Internet-Draft Abbreviated Title October 2010 +++++ + B + +++++ / | \ A-C Fiber has 30 wavelengths setup / | \ D-C Fiber has 20 Wavelengths setup / +++ \ / + D + \ / / +++ \ \ Most wavelengths on B-C fiber are used, only / / \ \ 10 wavelengths are still available. / / \ \ +++++ \ +++++ + A + ------------ + C + +++++ +++++ Figure 1 (a) Prioritize then Restore With the reference to Figure 2 we can consider a dual fiber cut on the path A-C and D-C. A lambda prioritization might be used to ensure high priority light paths be served first. This will ensure both a faster restoration time compared to other channels as well as the ability of high priority light paths to grab first (before other lower priority light paths) the available resources on the working fiber. +++++ + B + +++++ / | \ A-C Fiber has 30 wavelengths setup / | \ D-C Fiber has 20 Wavelengths setup / +++ \ / + D + \ Question is which wavelengths out of the 50 / / +++ \ \ are going to be restored (selection of / / X \ 10 only)? / / \ \ +++++ \ +++++ + A + ----- X ------ + C + +++++ +++++ Figure 2 Kattan, et al. Expires April 4, 2011 [Page 4] Internet-Draft Abbreviated Title October 2010 (b) Revertive Operation In this scenario, a fiber is being restored and hence having a high priority light paths restored first might or might not be desirable. Setting a revertive or not revertive option would be useful in this scenario. Moreover, in the event of multiple fiber cuts with only one fiber restored as an example, prioritizing light paths will ensure higher priority traffic will get the best service as well as up time once the WSON restoration mechanism kicks in. Other possibilities inlcude defining some others lambda properties like a "no not restore bit" or "Wait time to restore" to allow the control plane operates according to different restoration strategies. (c) Network Optimization Similar to revertive operation, prioritizing light paths will also be useful in network optimization. High priority traffic will always get the option to ride on the best available fiber path. Also high priority light path could be provided with the option to get the best performance OI parameters to chose from. (d) Service Level Agreement support This could be useful for DWDM service providers where light paths are tagged with different parameters so that to create a desirable and configurable level of SLA. This SLA could be derived from bandwidth (100G, 40G and 10G), traffic type (TDM vs IP/Eth or FC payload) or just a network management defined requirement. (e) Resource Contention In the event of one or multiple fiber cuts, we could be faced with a situation whereby the number of light paths to be restored is larger than the available light path resources on the working fiber (see Figure 2 above). Having light paths prioritization together with a wait-time-to-restore will ensure that the high priority traffic will be served first and hence will be able to grab the available resources first. 3. Lambda Properties Definitions This section provide a list of wavelengths properties that worths to include in a control plane. Priority. This information will allow a preferred treatment to a Kattan, et al. Expires April 4, 2011 [Page 5] Internet-Draft Abbreviated Title October 2010 wavelength with higher priority. Do Not Restore. If this information will not restore try to restore the wavelength after a failure. Lambda-Timer. This timer can be used as either hold-off-timer or wait-time-to-restore to control how the wavelelenght is managed during a protection and/or restoration actions. 4. Lambda Properties Encoding The lambda priority will be encoded over three bits. There are different encoding possibility depending on the protocol used to distribute this information over the control plane. It worth noting that GMPLS extension in [RFC4202] and [RFC4203] already define LSP priority bandwidth within Interface Switching Capability Descriptor sub-TLV. This concept however does not suffice for WSON LSP for the scenario represented above. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | TIMER |R| PRI | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3 The 3 bits PRI field represent the lambda priority encoding. Zero means no priority, Seven means maximum priority R is the "Do not restore bit". If set the wavelength will be exclude from any kind restoration Timer is a timer to delay restoration/protection actions on the wavelenghts. 8 bits with a granularity of 1 second will allow up to 255 seconds of delay on restoration. 4.1. OSPF Extensions In order to improve the WSON path computation it make sense to add such information through the chosen IGP. Current WSON proposal are available for OSPF-TE extentions. Kattan, et al. Expires April 4, 2011 [Page 6] Internet-Draft Abbreviated Title October 2010 Document [I-D.ietf-ccamp-rwa-wson-encode] report the information on how to encode Dynamic Link Information through the label set specification. Efficient encoding through a Link Attributes shall be identified. An initial proposal may looks like the label set attribute as explained in the following picture. The wavelength property encoding will be a sub-TLV (type TBD) of the link TLV. The set of 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TBD | Reserved | Length = 16 bytes | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Grid | C.S. | Reserved | n for lowest frequency = -11 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength Property Field <1> | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | .... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength Property Field | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4 Where: TBD: is the sub-TLV type (to be defined) The Grid provide the current WSON wavelength encoding in use and must match with the label set defined in [I-D.ietf-ccamp-general-constraint-encode]. A list of Wavelength property field, defined n Figure 4 in an order they match with the last label set advertised. 4.2. RSVP Extensions WSON signalling extentions are reported through [draft-bernstein-ccamp-wson-signaling-07]. In addition to this a new LSP_ATTRIBUTES as defined in [RFC5420] will be required to carry the lambda priority information. A new LSP_ATTRIBUTE shall include the Wavelength Property Field as defined in Figure 4 Kattan, et al. Expires April 4, 2011 [Page 7] Internet-Draft Abbreviated Title October 2010 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength Property | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 5 In this case the only one wavelenght property object will be required. 5. Acknowledgements 6. IANA Considerations This memo includes no request to IANA. All drafts are required to have an IANA considerations section (see the update of RFC 2434 [I-D.narten-iana-considerations-rfc2434bis] for a guide). If the draft does not require IANA to do anything, the section contains an explicit statement that this is the case (as above). If there are no requirements for IANA, the section will be removed during conversion into an RFC by the RFC Editor. 7. Security Considerations All drafts are required to have a security considerations section. See RFC 3552 [RFC3552] for a guide. 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. 8.2. Informative References [I-D.ietf-ccamp-general-constraint-encode] Bernstein, G., "General Network Element Constraint Encoding for GMPLS Controlled Networks", Kattan, et al. Expires April 4, 2011 [Page 8] Internet-Draft Abbreviated Title October 2010 draft-ietf-ccamp-general-constraint-encode-03 (work in progress), October 2010. [I-D.ietf-ccamp-gmpls-g-694-lambda-labels] Otani, T., Rabbat, R., Shiba, S., Guo, H., Miyazaki, K., Caviglia, D., Li, D., and T. Tsuritani, "Generalized Labels for Lambda-Switching Capable Label Switching Routers", draft-ietf-ccamp-gmpls-g-694-lambda-labels-07 (work in progress), April 2010. [I-D.ietf-ccamp-rwa-wson-encode] Bernstein, G., "Routing and Wavelength Assignment Information Encoding for Wavelength Switched Optical Networks", draft-ietf-ccamp-rwa-wson-encode-05 (work in progress), July 2010. [I-D.ietf-ccamp-rwa-wson-framework] Bernstein, G., Lee, Y., and W. Imajuku, "Framework for GMPLS and PCE Control of Wavelength Switched Optical Networks (WSON)", draft-ietf-ccamp-rwa-wson-framework-07 (work in progress), October 2010. [I-D.narten-iana-considerations-rfc2434bis] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", draft-narten-iana-considerations-rfc2434bis-09 (work in progress), March 2008. [RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629, June 1999. [RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC Text on Security Considerations", BCP 72, RFC 3552, July 2003. Authors' Addresses Moustafa Kattan (editor) Cisco DUBAI, 500321 UNITED ARAB EMIRATES Phone: +14085275101 Email: mkattan@cisco.com Kattan, et al. Expires April 4, 2011 [Page 9] Internet-Draft Abbreviated Title October 2010 Giovanni Martinelli Cisco Italy Phone: +39 039 209 2044 Email: giomarti@cisco.com David Bianchi Cisco Italy Phone: +39 039 2091505 Email: davbianc@cisco.com Nazih Ibrahim MOT/OGERO Lebabon Phone: +9613327863 Email: nibrahim@ogero.com Kattan, et al. Expires April 4, 2011 [Page 10]