--- 1/draft-ietf-ccamp-flexible-grid-rsvp-te-ext-01.txt 2015-01-30 00:14:51.145676902 -0800 +++ 2/draft-ietf-ccamp-flexible-grid-rsvp-te-ext-02.txt 2015-01-30 00:14:51.169677486 -0800 @@ -1,28 +1,28 @@ -Network Working Group Fatai Zhang +CCAMP Working Group Fatai Zhang Internet-Draft Xian Zhang Intended status: Standards Track Huawei Adrian Farrel Old Dog Consulting Oscar Gonzalez de Dios Telefonica D. Ceccarelli Ericsson -Expires: July 6, 2015 January 7, 2015 +Expires: July 30, 2015 January 30, 2015 RSVP-TE Signaling Extensions in support of Flexible Grid - draft-ietf-ccamp-flexible-grid-rsvp-te-ext-01.txt + draft-ietf-ccamp-flexible-grid-rsvp-te-ext-02.txt Abstract - This memo describes the extensions to the Resource reservation + This memo describes the extensions to the Resource reserVation Protocol Traffic Engineering (RSVP-TE) signaling protocol to support Label Switched Paths (LSPs) in a GMPLS-controlled network that includes devices using the flexible optical grid. 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 @@ -35,24 +35,24 @@ 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 July 6, 2015. + This Internet-Draft will expire on July 30, 2015. Copyright Notice - Copyright (c) 2014 IETF Trust and the persons identified as the + 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 (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 @@ -90,24 +90,24 @@ frequency grids for Wavelength Division Multiplexing (WDM) applications. A frequency grid is a reference set of frequencies used to denote allowed nominal central frequencies that may be used for defining applications that utilize WDM transmission. The channel spacing is the frequency spacing between two allowed nominal central frequencies. All of the wavelengths on a fiber use different central frequencies and occupy a designated range of frequency. Fixed grid channel spacing is selected from 12.5 GHz, 25 GHz, 50 GHz, 100 GHz and integer multiples of 100 GHz. But [G.694.1] also defines - ''flexible grids'', known as ''flexi-grid''. The terms ''frequency slot'' + "flexible grids", known as "flexi-grid". The terms "frequency slot" (i.e., the frequency range allocated to a specific channel and - unavailable to other channels within a flexible grid) and ''slot - width'' (i.e., the full width of a frequency slot in a flexible grid) + unavailable to other channels within a flexible grid) and "slot + width" (i.e., the full width of a frequency slot in a flexible grid) are introduced in [G.694.1] to define a flexible grid. [FLEX-FWK] defines a framework and the associated control plane requirements for the GMPLS based control of flexi-grid DWDM networks. [RFC6163] provides a framework for GMPLS and Path Computation Element (PCE) control of Wavelength Switched Optical Networks (WSONs), and [WSON-SIG] describes the requirements and protocol extensions for signaling to set up Label Switched Paths (LSPs) in WSONs. @@ -131,75 +131,76 @@ The architecture for establishing LSPs in a flexi-grid network is described in [FLEX-FWK]. An optical spectrum LSP occupies a specific frequency slot, i.e., a range of frequencies. The process of computing a route and the allocation of a frequency slot is referred to as Routing and Spectrum Assignment (RSA). [FLEX-FWK] describes three architectural approaches to RSA: combined RSA, separated RSA, and distributed SA. - The first two approaches are referred to as ''centralized SA'' because + The first two approaches are referred to as "centralized SA" because both routing and spectrum (frequency slot) assignment are performed by a centralized entity before the signaling procedure. In the case of centralized SA, the assigned frequency slot is specified in the RSVP-TE Path message during LSP setup. In the case of distributed SA, the slot width of the flexi-grid LSP is specified in the Path message, allowing the network elements to select the frequency slot to be used when they process the RSVP-TE messages. If the capability to switch or convert the whole optical spectrum allocated to an optical spectrum LSP is not available at some nodes along the path of the LSP, the LSP is subject to the Optical - ''Spectrum Continuity Constraint'' as described in [FLEX-FWK]. + "Spectrum Continuity Constraint" as described in [FLEX-FWK]. The remainder of this section states the additional requirements for signaling in a flexi-grid network. 3.1. Slot Width The slot width is an end-to-end parameter representing how much frequency resource is requested for a flexi-grid LSP. It is the equivalent of optical bandwidth, although the amount of bandwidth associated with a slot width will depend on the signal encoding. Different LSPs may request different amounts of frequency resource - in flexible grid networks, so the slot width needs to be carried in - the signaling message during LSP establishment. This enables the - nodes along the LSP to know how much frequency resource has been - requested (in a Path message) and has been allocated (by a Resv - message) for the LSP. + in flexible grid networks, so the slot width MUST be carried in the + signaling message during LSP establishment. This enables the nodes + along the LSP to know how much frequency resource has been requested + (in a Path message) and has been allocated (by a Resv message) for + the LSP. 3.2. Frequency Slot The frequency slot information identifies which part of the frequency spectrum is allocated on each link for an LSP in a flexi- grid network. - This information is required in a Resv message to indicate, hop-by- - hop, the central frequency of the allocated resource. In combination - with the slot width indicated in a Resv message (see Section 3.1) - the central frequency carried in a Resv message identifies the - resources reserved for the LSP (known as the frequency slot). + This information MUST be present in a Resv message to indicate, hop- + by-hop, the central frequency of the allocated resource. In + combination with the slot width indicated in a Resv message (see + Section 3.1) the central frequency carried in a Resv message + identifies the resources reserved for the LSP (known as the + frequency slot). The frequency slot can be represented by the two parameters as follows: Frequency slot = [(central frequency) - (slot width)/2] ~ [(central frequency) + (slot width)/2] As is common with other resource identifiers (i.e., labels) in GMPLS signaling, it must be possible for the head-end LSP when sending a Path message to suggest or require the central frequency to be used for the LSP. Furthermore, for bidirectional LSPs, the Path message - must be able to specify the central frequency to be used for reverse + MUST be able to specify the central frequency to be used for reverse direction traffic. As described in [G.694.1], the allowed frequency slots for the flexible DWDM grid have a nominal central frequency (in THz) defined by: 193.1 + n * 0.00625 where n is zero or a positive or negative integer. @@ -235,22 +236,22 @@ traffic parameters for a flexi-grid LSP encode the slot width. This document defines new C-Types for the SENDER_TSPEC and FLOWSPEC objects to carry Spectrum Switched Optical Network (SSON) traffic parameters: SSON SENDER_TSPEC: Class = 12, C-Type = TBD1. SSON FLOWSPEC: Class = 9, C-Type = TBD2. - The SSON traffic parameters carried in both objects have the same - format as shown in Figure 1. + The SSON traffic parameters carried in both objects MUST have the + same format as shown in Figure 1. 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 | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: The SSON Traffic Parameters m (16 bits): the slot width is specified by m*12.5 GHz. @@ -273,21 +274,21 @@ 4.2. Generalized Label In the case of a flexible grid network, the labels that have been requested or allocated as signaled in the RSVP-TE objects are encoded as described in [FLEX-LBL]. This new label encoding can appear in any RSVP-TE object or sub-object that can carry a label. As noted in Section 4.2 of [FLEX-LBL], the m parameter forms part of the label as well as part of the traffic parameters. - As described in Section 4.3 of [FLEX-LBL], a ''compound label'', + As described in Section 4.3 of [FLEX-LBL], a "compound label", constructed from a concatenation of the flexi-grid LABELs, is used when signaling an LSP that uses multiple flexi-grid slots. 4.3. Signaling Procedures There are no differences between the signaling procedure described for LSP control in [FLEX-FWK] and those required for use in a fixed- grid network [WSON-SIG]. Obviously, the TSpec, FlowSpec, and label formats described in Sections 4.1 and 4.2 are used. The signaling procedures for distributed SA and centralized SA can be applied. @@ -419,50 +420,50 @@ 10.1. Normative References [RFC2119] S. Bradner, "Key words for use in RFCs to indicate requirements levels", RFC 2119, March 1997. [RFC3473] L. Berger, Ed., "Generalized Multi-Protocol Label Switching (GMPLS) Signaling Resource ReserVation Protocol- Traffic Engineering (RSVP-TE) Extensions", RFC 3473, January 2003. - [G.694.1] ITU-T Recommendation G.694.1 (revision 2), ''Spectral grids - for WDM applications: DWDM frequency grid'', February 2012. + [G.694.1] ITU-T Recommendation G.694.1 (revision 2), "Spectral grids + for WDM applications: DWDM frequency grid", February 2012. - [FLEX-LBL]King, D., Farrel, A. and Y. Li, ''Generalized Labels for + [FLEX-LBL]King, D., Farrel, A. and Y. Li, "Generalized Labels for the Flexi-Grid in Lambda Switched Capable (LSC) Label - Switching Routers'', draft-ietf-ccamp-flexigrid-lambda- + Switching Routers", draft-ietf-ccamp-flexigrid-lambda- label, work in progress. 10.2. Informative References [RFC2205] Braden, R., Zhang L., Berson, S., Herzog, S. and S. Jamin, - ''Resource ReServation Protocol (RSVP) - - Version 1, + "Resource ReServation Protocol (RSVP) - Version 1, Functional Specification', RFC2205, September 1997. [RFC5920] L. Fang et al., "Security Framework for MPLS and GMPLS Networks", RFC 5920, July 2010. [RFC6163] Y. Lee, G. Bernstein and W. Imajuku, "Framework for GMPLS and Path Computation Element (PCE) Control of Wavelength Switched Optical Networks (WSONs)", RFC 6163, April 2011. [RFC6982] Sheffer, Y. and A. Farrel, "Improving Awareness of Running Code: The Implementation Status Section", RFC 6982, July 2013. [RFC Editor Note: This reference can be removed when Section 7 is removed] [FLEX-FWK] Gonzalez de Dios, O, Casellas R., Zhang, F., Fu, X., - Ceccarelli, D., and I. Hussain, ''Framework and + Ceccarelli, D., and I. Hussain, "Framework and Requirements for GMPLS based control of Flexi-grid DWDM networks', draft-ietf-cammp-flexi-grid-fwk, work in progress. [WSON-SIG] G. Bernstein, Sugang Xu, Y. Lee, G. Martinelli and Hiroaki Harai, "Signaling Extensions for Wavelength Switched Optical Networks", draft-ietf-ccamp-wson- signaling, work in progress. 11. Contributors' Addresses