CCAMP Working Group D. Papadimitriou - Editor Category: Internet Draft Alcatel Expiration Date: May 2003 November 2002 Generalized MPLS Signalling Extensions for G.709 Optical Transport Networks Control draft-ietf-ccamp-gmpls-g709-03.txt Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026 [1]. 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. Abstract This document is a companion to the Generalized MPLS (GMPLS) signalling documents. It describes the technology specific information needed to extend GMPLS signalling to control Optical Transport Networks (OTN); it also includes the so-called pre-OTN developments. *** DISCLAIMER *** In this document, the presented views on ITU-T G.709 OTN Recommendation (and referenced) are intentionally restricted as needed from the GMPLS perspective within the IETF CCAMP WG context. Hence, the objective of this document is not to replicate the content of the ITU-T OTN recommendations. Therefore, the reader interested in going into more details concerning the corresponding technologies is strongly invited to consult the corresponding ITU- T documents (also referenced in this memo). D.Papadimitriou et al. - Internet Draft û Expires May 2003 1 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 Table of Content Status of this Memo 1 Abstract 1 Table of Content 2 1. Introduction 2 2. GMPLS Extensions for G.709 û Overview 3 3. Generalized Label Request 4 3.1 Technology Independent Part 4 3.1.1. LSP Encoding Type 4 3.1.2. Switching-Type 5 3.1.3. Generalized-PID (G-PID) 5 3.2. G.709 Traffic-Parameters 7 3.2.1. Signal Type (ST) 7 3.2.2. Number of Multiplexed Components (NMC) 8 3.2.3. Number of Virtual Components (NVC) 8 3.2.4. Multiplier (MT) 9 3.2.5. Reserved Fields 9 4. Generalized Label 9 4.1. ODUk Label Space 9 4.2. Label Distribution Rules 11 4.3. OCh Label Space 12 5. Examples 12 6. Signalling Protocol Extensions 13 6.1. RSVP-TE Details 13 6.2. CR-LDP Details 14 7. Security Considerations 15 8. IANA Considerations 15 9. Acknowledgments 15 10. Intellectual Property Notice 15 11. References 16 11.1 Normative References 16 12. Contributors 17 13. AuthorÆs Address 18 Appendix 1 û Abbreviations 19 Appendix 2 û G.709 Indexes 19 Full Copyright Statement 21 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. In addition, the reader is assumed to be familiar with the terminology used in ITU-T [ITUT-G709] as well as [GMPLS-SIG], [GMPLS-RSVP] and [GMPLS-LDP]. Abbreviations used in this document are also detailed in Appendix 1. Changes from v02.txt to v03.txt: Editorial and text clarifications Add G-PID values for ESCON and FICON D.Papadimitriou et al. - Internet Draft û Expires May 2003 2 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 1. Introduction Generalized MPLS extends MPLS from supporting Packet Switching Capable (PSC) interfaces and switching to include support of three new classes of interfaces and switching: Time-Division Multiplex (TDM), Lambda Switch (LSC) and Fiber-Switch (FSC) Capable. A functional description of the extensions to MPLS signaling needed to support these new classes of interfaces and switching is provided in [GMPLS-SIG]. [GMPLS-RSVP] describes RSVP-TE specific formats and mechanisms needed to support all four classes of interfaces, and CR-LDP extensions can be found in [GMPLS-LDP]. This document presents the technology details that are specific to G.709 Optical Transport Networks (OTN) as specified in the ITU-T G.709 recommendation [ITUT-G709] (and referenced documents), including pre-OTN developments. Per [GMPLS-SIG], G.709 specific parameters are carried through the signaling protocol in traffic parameter specific objects. The G.709 traffic parameters defined hereafter (see Section 3.2) MUST be used when the label is encoded as defined in this document. Moreover, the label MUST be encoded as defined in Section 4 when these G.709 traffic parameters are used. Note: in the context of this memo, by pre-OTN developments, one refers to Optical Channel, Digital Wrapper and Forward Error Correction (FEC) solutions that are not fully G.709 compliant. Details concerning pre-OTN SONET/SDH based solutions including Optical Sections (OS), Regenerator Section (RS)/Section and Multiplex Section (MS)/ Line overhead transparency are covered in [GMPLS-SONET-SDH]. 2. GMPLS Extensions for G.709 - Overview Although G.709 defines several networking layers (OTS, OMS, OPS, OCh, OChr constituting the optical transport hierarchy and OTUk, ODUk constituting the digital transport hierarchy) only the OCh (Optical Channel) and the ODUk (Optical Channel Data Unit) layers are defined as switching layers. Both OCh (but not OChr) and ODUk layers include the overhead for supervision and management. The OCh overhead is transported in a non-associated manner (so also referred to as the non-associated overhead û naOH) in the OTM Overhead Signal (OOS), together with the OTS and OMS non-associated overhead. The OOS is transported via a dedicated wavelength referred to as the Optical Supervisory Channel (OSC). It should be noticed that the naOH is only functionally specified and as such open to vendor specific solutions. The ODUk overhead is transported in an associated manner as part of the digital ODUk frame. As described in [ITUT-G709], in addition to the support of ODUk mapping into OTUk (k = 1, 2, 3), [ITUT-G.709] supports ODUk D.Papadimitriou et al. - Internet Draft û Expires May 2003 3 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 multiplexing. It refers to the multiplexing of ODUj (j = 1, 2) into an ODUk (k > j) signal, in particular: - ODU1 into ODU2 multiplexing - ODU1 into ODU3 multiplexing - ODU2 into ODU3 multiplexing - ODU1 and ODU2 into ODU3 multiplexing Therefore, adapting GMPLS to control G.709 OTN, can be achieved by considering that: - a Digital Path layer by extending the previously defined ôDigital Wrapperö in [GMPLS-SIG] corresponding to the ODUk (digital) path layer. - an Optical Path layer by extending the ôLambdaö concept defined in [GMPLS-SIG] to the OCh (optical) path layer. - a label space structure by considering a tree whose root is an OTUk signal and leaves the ODUj signals (k >= j); enabling to identify the exact position of a particular ODUj signal in an ODUk multiplexing structure. Thus, GMPLS extensions for G.709 need to cover the Generalized Label Request, the Generalized Label as well as the specific technology dependent objects included in the so-called traffic parameters as specified in [GMPLS-SONET-SDH] for SONET/SDH networks. Moreover, since the multiplexing in the digital domain (such as ODUk multiplexing) has been considered in the amended version of the G.709 recommendation (October 2001), this document also proposes a label space definition suitable for that purpose. Notice also that one directly uses the G.709 ODUk (i.e. Digital Path) and OCh (i.e. Optical Path) layers in order to define the corresponding label spaces. 3. Generalized Label Request The Generalized Label Request as defined in [GMPLS-SIG], includes a technology independent part and a technology dependent part (i.e. the traffic parameters). In this section, both parts are extended to accommodate the GMPLS Signalling to the G.709 transport plane recommendation (see [ITUT-G709]). 3.1 Technology Independent Part As defined in [GMPLS-SIG], the LSP Encoding Type, the Switching Type and the Generalized Protocol Identifier (Generalized-PID) constitute the technology independent part of the Generalized Label Request. The encoding of the corresponding RSVP-TE object and CR-LDP TLV is specified in [GMPLS-RSVP] Section 2.1 and [GMPLS-LDP] Section 2.1, respectively. As mentioned here above, this document extends the LSP Encoding Type, Switching Type and G-PID (Generalized-PID) values to accommodate G.709 recommendation [ITUT-G709]. 3.1.1 LSP Encoding Type D.Papadimitriou et al. - Internet Draft û Expires May 2003 4 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 Since G.709 defines two networking layers (ODUk layers and OCh layer), the LSP Encoding Type code-points can reflect these two layers currently defined in [GMPLS-SIG] as ôDigital Wrapperö and ôLambdaö code. The LSP Encoding Type is specified per networking layer or more precisely per group of functional networking layer: the ODUk layers and the OCh layer. Therefore, the current ôDigital Wrapperö code-point defined in [GMPLS-SIG] can be replaced by two separated code-points: - code-point for the G.709 Digital Path layer - code-point for the non-standard Digital Wrapper layer In the same way, two separated code-points can replace the current defined ôLambdaö code-point: - code-point for the G.709 Optical Channel layer - code-point for the non-standard Lambda layer (also referred to as Lambda layer which includes the pre-OTN Optical Channel layer) Consequently, the following additional code-points for the LSP Encoding Type are defined: Value Type ----- ---- 12 G.709 ODUk (Digital Path) 13 G.709 Optical Channel Moreover, the code-point for the G.709 Optical Channel (OCh) layer will indicate the capability of an end-system to use the G.709 non- associated overhead (naOH) i.e. the OTM Overhead Signal (OOS) multiplexed into the OTM-n.m interface signal. 3.1.2 Switching Type The Switching Type indicates the type of switching that should be performed at the termination of a particular link. This field is only needed for links that advertise more than one type of switching capability (see [GMPLS-RTG]). Here, no additional values are to be considered in order to accommodate G.709 switching types since an ODUk switching (and so LSPs) belongs to the TDM class while an OCh switching (and so LSPs) to the Lambda class (i.e. LSC). Moreover, in a strict layered G.709 network, when a downstream node receives a Generalized Label Request including one of these values for the Switching Type field, this value SHOULD be ignored. 3.1.3 Generalized-PID (G-PID) D.Papadimitriou et al. - Internet Draft û Expires May 2003 5 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 The G-PID (16 bits field) as defined in [GMPLS-SIG], identifies the payload carried by an LSP, i.e. an identifier of the client layer of that LSP. This identifier is used by the endpoints of the G.709 LSP. The G-PID can take one of the following values when the client payload is transported over the Digital Path layer, in addition to the payload identifiers defined in [GMPLS-SIG]: - CBRa: asynchronous Constant Bit Rate i.e. mapping of STM-16/OC-48, STM-64/OC-192 and STM-256/OC-768 - CBRb: bit synchronous Constant Bit Rate i.e. mapping of STM-16/OC- 48, STM-64/OC-192 and STM-256/OC-768 - ATM : mapping at 2.5, 10 and 40 Gbps - BSOT: non-specific client Bit Stream with Octet Timing i.e. Mapping of 2.5, 10 and 40 Gbps Bit Stream - BSNT: non-specific client Bit Stream without Octet Timing i.e. Mapping of 2.5, 10 and 40 Gbps Bit Stream - ODUk: transport of Digital Paths at 2.5, 10 and 40 Gbps - ESCON (Enterprise Systems Connection) - FICON (Fiber Connection) The G-PID can take one of the following values when the client payload is transported over the Optical Channel layer, in addition to the payload identifiers defined in [GMPLS-SIG]: - CBR: Constant Bit Rate i.e. mapping of STM-16/OC-48, STM-64/OC-192 and STM-256/OC-768 - OTUk/OTUkV: transport of Digital Section at 2.5, 10 and 40 Gbps Also, when client payloads such as Ethernet MAC/PHY and IP/PPP are encapsulated through the Generic Framing Procedure (GFP) as described in ITU-T G.7041, dedicated G-PID values are defined. Notice that additional G-PID values such as ESCON, FICON and Fiber Channel could complete this list in future releases. In order to include pre-OTN developments as defined above, the G-PID can take one of the values currently defined in [GMPLS-SIG] when the following client payloads are transported over a so-called lambda: - Gigabit Ethernet (1 Gbps and 10 Gbps) - Fiber Channel The following table summarizes the G-PID with respect to the LSP Encoding Type: Value G-PID Type LSP Encoding Type ----- ---------- ----------------- 47 G.709 ODUj G.709 ODUk (with k > j) 48 G.709 OTUk(v) G.709 OCh ODUk mapped into OTUk(v) 49 CBR/CBRa G.709 ODUk, G.709 OCh 50 CBRb G.709 ODUk 51 BSOT G.709 ODUk 52 BSNT G.709 ODUk 53 IP/PPP (GFP) G.709 ODUk (and SDH) 54 Ethernet MAC (framed GFP) G.709 ODUk (and SDH) D.Papadimitriou et al. - Internet Draft û Expires May 2003 6 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 55 Ethernet PHY (transparent GFP) G.709 ODUk (and SDH) 56 ESCON G.709 ODUk, Lambda, Fiber 57 FICON G.709 ODUk, Lambda, Fiber Note: Value 49 and 50 includes mapping of SDH The following table summarizes the update of the G-PID values defined in [GMPLS-SIG]: Value G-PID Type LSP Encoding Type ----- ---------- ----------------- 32 ATM Mapping SDH, G.709 ODUk 33 Ethernet PHY SDH, G.709 OCh, Lambda, Fiber 34 Sonet/SDH G.709 OCh, Lambda, Fiber 35 Reserved (SONET Dep.) G.709 OCh, Lambda, Fiber 3.2 G.709 Traffic-Parameters When G.709 Digital Path Layer or G.709 Optical Channel Layer is specified in the LSP Encoding Type field, the information referred to as technology dependent information (or simply traffic- parameters) is carried additionally to the one included in the Generalized Label Request and is defined 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Signal Type | Reserved | NMC | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | NVC | Multiplier (MT) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ In this frame, NMC stands for Number of Multiplexed Components, NVC for Number of Virtual Components and MT for Multiplier. Each of these fields is tailored to support G.709 LSP requests. 3.2.1 Signal Type (ST) This field (8 bits) indicates the type of G.709 Elementary Signal that comprises the requested LSP. The permitted values are: Value Type ----- ---- 0 Irrelevant 1 ODU1 (i.e. 2.5 Gbps) 2 ODU2 (i.e. 10 Gbps) 3 ODU3 (i.e. 40 Gbps) 4 Reserved 5 Reserved 6 OCh at 2.5 Gbps 7 OCh at 10 Gbps D.Papadimitriou et al. - Internet Draft û Expires May 2003 7 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 8 OCh at 40 Gbps 9-255 Reserved The value of the Signal Type field depends on LSP Encoding Type value defined in Section 3.1.1 and [GMPLS-SIG]: - if the LSP Encoding Type value is the G.709 Digital Path layer then the valid values are the ODUk signals (k = 1, 2 or 3) - if the LSP Encoding Type value is the G.709 Optical Channel layer then the valid values are the OCh at 2.5, 10 or 40 Gbps - if the LSP Encoding Type is ôLambdaö (which includes the pre-OTN Optical Channel layer) then the valid value is irrelevant (Signal Type = 0) - if the LSP Encoding Type is ôDigital Wrapperö, then the valid value is irrelevant (Signal Type = 0) Several transforms can be sequentially applied on the Elementary Signal to build the Final Signal being actually requested for the LSP. Each transform application is optional and MUST be ignored if zero, except the Multiplier (MT) that cannot be zero and MUST be ignored if equal to one. Transforms MUST be applied strictly in the following order: - First, virtual concatenation (by using the NVC field) can be optionally applied directly on the Elementary Signal to form a Composed Signal - Second, a multiplication (by using the Multiplier field) can be optionally applied either directly on the Elementary Signal, or on the virtually concatenated signal obtained from the first phase. The resulting signal is referred to as Final Signal. 3.2.2 Number of Multiplexed Components (NMC) The NMC field (16 bits) indicates the number of ODU tributary slots used by an ODUj when multiplexed into an ODUk (k > j) for the requested LSP. This field is not applicable when an ODUk is mapped into an OTUk and irrelevant at the Optical Channel layer. In both cases, it MUST be set to zero (NMC = 0) when sent and should be ignored when received. When applied at the Digital Path layer, in particular for ODU2 connections multiplexed into one ODU3 payload, the NMC field specifies the number of individual tributary slots (NMC = 4) constituting the requested connection. These components are still processed within the context of a single connection entity. For all other currently defined multiplexing cases (see Section 2), the NMC field is set to 1. 3.2.3 Number of Virtual Components (NVC) The NVC field (16 bits) is dedicated to ODUk virtual concatenation (i.e. ODUk Inverse Multiplexing) purposes. It indicates the number of ODU1, ODU2 or ODU3 Elementary Signals that are requested to be virtually concatenated to form an ODUk-Xv signal. By definition, these signals MUST be of the same type. D.Papadimitriou et al. - Internet Draft û Expires May 2003 8 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 This field is set to 0 (default value) to indicate that no virtual concatenation is requested. Note that the current usage of this field only applies for G.709 ODUk LSP i.e. values greater than zero are only acceptable for ODUk Signal Types. Therefore, it MUST be set to zero (NVC = 0) when requesting a G.709 OCh LSP and should be ignored when received. 3.2.4 Multiplier (MT) The Multiplier field (16 bits) indicates the number of identical Elementary Signals or Composed Signals requested for the LSP i.e. that form the Final Signal. A Composed Signal is the resulting signal from the application of the NMC and NVC fields to an elementary Signal Type. GMPLS signalling currently implies that all the Composed Signals must be part of the same LSP. This field is set to one (default value) to indicate that exactly one instance of a signal is being requested. Intermediate and egress nodes MUST verify that the node itself and the interfaces on which the LSP will be established can support the requested multiplier value. If the requested values can not be supported, the receiver node MUST generate a PathErr/NOTIFICATION message (see Section 6.1/6.2, respectively). Zero is an invalid value. If received, the node MUST generate a PathErr/NOTIFICATION message (see Section 6.1/6.2, respectively). 3.2.5 Reserved Fields The reserved fields (8 bits in row 1 and 32 bits fields in row 3) are dedicated for future use. Reserved bits SHOULD be set to zero when sent and MUST be ignored when received. 4. Generalized Label This section describes the Generalized Label value space for Digital Paths and Optical Channels. The Generalized Label is defined in [GMPLS-SIG]. The format of the corresponding RSVP-TE object and CR- LDP TLV is specified in [GMPLS-RSVP] Section 2.2 and [GMPLS-LDP] Section 2.2, respectively. The label distribution rules detailed in Section 4.2, follow when applicable the ones defined in [GMPLS-SONET-SDH]. 4.1 ODUk Label Space At the Digital Path layer (i.e. ODUk layers), G.709 defines three different client payload bit rates. An Optical Data Unit (ODU) frame has been defined for each of these bit rates. ODUk refers to the frame at bit rate k, where k = 1 (for 2.5 Gbps), 2 (for 10 Gbps) or 3 (for 40 Gbps). D.Papadimitriou et al. - Internet Draft û Expires May 2003 9 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 In addition to the support of ODUk mapping into OTUk, the G.709 label space supports the sub-levels of ODUk multiplexing. ODUk multiplexing refers to multiplexing of ODUj (j = 1, 2) into an ODUk (k > j), in particular: - ODU1 into ODU2 multiplexing - ODU1 into ODU3 multiplexing - ODU2 into ODU3 multiplexing - ODU1 and ODU2 into ODU3 multiplexing More precisely, ODUj into ODUk multiplexing (k > j) is defined when an ODUj is multiplexed into an ODUk Tributary Unit Group (i.e. an ODTUG constituted by ODU tributary slots) which is mapped into an OPUk. The resulting OPUk is mapped into an ODUk and the ODUk is mapped into an OTUk. Therefore, the label space structure is a tree whose root is an OTUk signal and leaves the ODUj signals (k >= j) that can be transported via the tributary slots and switched between these slots. A G.709 Digital Path layer label identifies the exact position of a particular ODUj signal in an ODUk multiplexing structure. The G.709 Digital Path Layer label or ODUk label has the following format: 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 | t3 | t2 |t1| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The specification of the three fields t1, t2 and t3 self- consistently characterizes the ODUk label space. The value space of the t1, t2 and t3 fields is defined as follows: 1. t1 (1-bit): - t1=1 indicates an ODU1 signal. - t1 is not significant for the other ODUk signal types (t1=0). 2. t2 (3-bit): - t2=1 indicates a not further sub-divided ODU2 signal. - t2=2->5 indicates the tributary slot (t2th-2) used by the ODU1 in an ODTUG2 mapped into an ODU2 (via OPU2). - t2 is not significant for an ODU3 (t2=0). 3. t3 (6-bit): - t3=1 indicates a not further sub-divided ODU3 signal. - t3=2->17 indicates the tributary slot (t3th-1) used by the ODU1 in an ODTUG3 mapped into an ODU3 (via OPU3). - t3=18->33 indicates the tributary slot (t3th-17) used by the ODU2 in an ODTUG3 mapped into an ODU3 (via OPU3). D.Papadimitriou et al. - Internet Draft û Expires May 2003 10 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 Note: in case of ODU2 into ODU3 multiplexing, 4 labels are required to identify the 4 tributary slots used by the ODU2; these tributary time slots have to be allocated in ascending order. If the label sub-field value t[i]=1 (i, j = 1, 2 or 3) and t[j]=0 (j > i), the corresponding ODUk signal ODU[i] is directly mapped into the corresponding OTUk signal (k=i). This is referred to as the mapping of an ODUk signal into an OTUk of the same order. Therefore, the numbering starts at 1; zero is used to indicate a non- significant field. A label field equal to zero is an invalid value. Examples: - t3=0, t2=0, t1=1 indicates an ODU1 mapped into an OTU1 - t3=0, t2=1, t1=0 indicates an ODU2 mapped into an OTU2 - t3=1, t2=0, t1=0 indicates an ODU3 mapped into an OTU3 - t3=0, t2=3, t1=0 indicates the ODU1 in the second tributary slot of the ODTUG2 mapped into an ODU2 (via OPU2) mapped into an OTU2 - t3=5, t2=0, t1=0 indicates the ODU1 in the fourth tributary slot of the ODTUG3 mapped into an ODU3 (via OPU3) mapped into an OTU3 4.2 Label Distribution Rules In case of ODUk in OTUk mapping, only one of label can appear in the Generalized Label. In case of ODUj in ODUk (k > j) multiplexing, the explicit ordered list of the labels in the multiplex is given (this list can be restricted to only one label when NMC = 1). Each label indicates a component (ODUj tributary slot) of the multiplexed signal. The order of the labels must reflect the order of the ODUj into the multiplex (not the physical order of tributary slots). In case of ODUk virtual concatenation, the explicit ordered list of all labels in the concatenation is given. Each label indicates a component of the virtually concatenated signal. The order of the labels must reflect the order of the ODUk to concatenate (not the physical order of time-slots). This representation limits virtual concatenation to remain within a single (component) link. In case of multiplexed virtually concatenated signals, the first set of labels indicates the components (ODUj tributary slots) of the first virtually concatenated signal, the second set of labels indicates the components (ODUj tributary slots) of the second virtually concatenated signal, and so on. In case of multiplication (i.e. when using the MT field), the explicit ordered list of all labels taking part in the composed signal is given. The above representation limits multiplication to remain within a single (component) link. In case of multiplication of multiplexed/virtually concatenated signals, the first set of labels indicates the components of the first multiplexed/virtually concatenated signal, the second set of labels indicates components of the second multiplexed/virtually concatenated signal, and so on. D.Papadimitriou et al. - Internet Draft û Expires May 2003 11 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 Note: As defined in [GMPLS-SIG], label field values only have significance between two neighbors, and the receiver may need (in some particular cases) to convert the received value into a value that has local significance. 4.3 Optical Channel Label Space At the Optical Channel layer, the label space must be consistently defined as a flat space whose values reflect the local assignment of OCh identifiers corresponding to the OTM-n.m sub-interface signals (m = 1, 2 or 3). Note that these identifiers do not cover OChr since the corresponding Connection Function (OChr-CF) between OTM- nr.m/OTM-0r.m is not defined in [ITUT-G798]. The OCh label space values are defined by either absolute values (i.e. channel identifiers or Channel ID also referred to as wavelength identifiers) or relative values (channel spacing also referred to as inter-wavelength spacing). The latter is strictly confined to a per-port label space while the former could be defined as a local or a global (per node) label space. Such an OCh label space is applicable to both OTN Optical Channel layer and pre-OTN Optical Channel layer. Optical Channel label encoding (and distribution) rules are defined in [GMPSL-SIG]. They MUST be used for the Upstream Label, the Suggested Label and the Generalized Label. 5. Examples The following examples are given in order to illustrate the processing described in the previous sections of this document. 1. ODUk in OTUk mapping: when one ODU1 (ODU2 or ODU3) signal is directly transported in an OTU1 (OTU2 or OTU3), the upstream node requests results simply in an ODU1 (ODU2 or ODU3) signal request. In such conditions, the downstream node has to return a unique label since the ODU1 (ODU2 or ODU3) is directly mapped into the corresponding OTU1 (OTU2 or OTU3). Since a single ODUk signal is requested (Signal Type = 1, 2 or 3), the downstream node has to return a single ODUk label which can be for instance one of the following when the Signal Type = 1: - t3=0, t2=0, t1=1 indicating a single ODU1 mapped into an OTU1 - t3=0, t2=1, t1=0 indicating a single ODU2 mapped into an OTU2 - t3=1, t2=0, t1=0 indicating a single ODU3 mapped into an OTU3 2. ODU1 into ODUk multiplexing (k > 1): when one ODU1 is multiplexed into the payload of a structured ODU2 (or ODU3), the upstream node requests results simply in a ODU1 signal request. In such conditions, the downstream node has to return a unique label since the ODU1 is multiplexed into one ODTUG2 (or ODTUG3). D.Papadimitriou et al. - Internet Draft û Expires May 2003 12 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 The latter is then mapped into the ODU2 (or ODU3) via OPU2 (or OPU3) and then mapped into the corresponding OTU2 (or OTU3). Since a single ODU1 multiplexed signal is requested (Signal Type = 1 and NMC = 1), the downstream node has to return a single ODU1 label which can take for instance one of the following values: - t3=0,t2=4,t1=0 indicates the ODU1 in the third TS of the ODTUG2 - t3=2,t2=0,t1=0 indicates the ODU1 in the first TS of the ODTUG3 - t3=7,t2=0,t1=0 indicates the ODU1 in the sixth TS of the ODTUG3 3. ODU2 into ODU3 multiplexing: when one unstructured ODU2 is multiplexed into the payload of a structured ODU3, the upstream node requests results simply in a ODU2 signal request. In such conditions, the downstream node has to return four labels since the ODU2 is multiplexed into one ODTUG3. The latter is mapped into an ODU3 (via OPU3) and then mapped into an OTU3. Since an ODU2 multiplexed signal is requested (Signal Type = 2, and NMC = 4), the downstream node has to return four ODU labels which can take for instance the following values: - t3=18, t2=0, t1=0 (first part of ODU2 in first TS of ODTUG3) - t3=22, t2=0, t1=0 (second part of ODU2 in fifth TS of ODTUG3) - t3=23, t2=0, t1=0 (third part of ODU2 in sixth TS of ODTUG3) - t3=26, t2=0, t1=0 (fourth part of ODU2 in ninth TS of ODTUG3) 4. When a single OCh signal of 40 Gbps is requested (Signal Type = 8), the downstream node must return a single wavelength label as specified in [GMPLS-SIG]. 5. When requesting multiple ODUk LSP (i.e. with a multiplier (MT) value > 1), an explicit list of labels is returned to the requestor node. When the downstream node receives a request for a 4 x ODU1 signal (Signal Type = 1, NMC = 1 and MT = 4) multiplexed into a ODU3, it returns an ordered list of four labels to the upstream node: the first ODU1 label corresponding to the first signal of the LSP, the second ODU1 label corresponding to the second signal of the LSP, etc. For instance, the corresponding labels can take the following values: - First ODU1: t3=2, t2=0, t1=0 (in first TS of ODTUG3) - Second ODU1: t3=10, t2=0, t1=0 (in ninth TS of ODTUG3) - Third ODU1: t3=7, t2=0, t1=0 (in sixth TS of ODTUG3) - Fourth ODU1: t3=6, t2=0, t1=0 (in fifth TS of ODTUG3) 6. Signalling Protocol Extensions This section specifies the [GMPLS-RSVP] and [GMPLS-LDP] protocol extensions needed to accommodate G.709 traffic parameters. 6.1 RSVP-TE Details D.Papadimitriou et al. - Internet Draft û Expires May 2003 13 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 For RSVP-TE, the G.709 traffic parameters are carried in the G.709 SENDER_TSPEC and FLOWSPEC objects. The same format is used both for SENDER_TSPEC object and FLOWSPEC objects. The content of the objects is defined above in Section 3.2. The objects have the following class and type for G.709: - G.709 SENDER_TSPEC Object: Class = 12, C-Type = TBA - G.709 FLOWSPEC Object: Class = 9, C-Type = TBA There is no Adspec associated with the SONET/SDH SENDER_TSPEC. Either the Adspec is omitted or an Int-serv Adspec with the Default General Characterization Parameters and Guaranteed Service fragment is used, see [RFC2210]. For a particular sender in a session the contents of the FLOWSPEC object received in a Resv message SHOULD be identical to the contents of the SENDER_TSPEC object received in the corresponding Path message. If the objects do not match, a ResvErr message with a "Traffic Control Error/Bad Flowspec value" error SHOULD be generated. Intermediate and egress nodes MUST verify that the node itself and the interfaces on which the LSP will be established can support the requested Signal Type, NMC and NVC values (as defined in Section 3.2). If the requested value(s) can not be supported, the receiver node MUST generate a PathErr message with a "Traffic Control Error/ Service unsupported" indication (see [RFC2205]). In addition, if the MT field is received with a zero value, the node MUST generate a PathErr message with a "Traffic Control Error/Bad Tspec value" indication (see [RFC2205]). 6.2 CR-LDP Details For CR-LDP, the G.709 traffic parameters are carried in the G.709 Traffic Parameters TLV. The content of the TLV is defined in Section 3.2. The header of the TLV has the following format: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|F| Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The type field indicates G.709 traffic parameters: 0xTBA Intermediate and egress nodes MUST verify that the node itself and the interfaces on which the LSP will be established can support the requested Signal Type, NMC and NVC values (as defined in Section 3.2). If the requested value(s) can not be supported, the receiver node MUST generate a NOTIFICATION message with a "Resource Unavailable" status code (see [RFC3212]). D.Papadimitriou et al. - Internet Draft û Expires May 2003 14 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 In addition, if the MT field is received with a zero value, the node MUST generate a NOTIFICATION message with a "Resource Unavailable" status code (see [RFC3212]). 7. Security Considerations This draft introduces no new security considerations to either [GMPLS-RSVP] or [GMPLS-LDP]. GMPLS security is described in section 11 of [GMPLS-SIG], in [RFC-3212] and in [RFC-3209]. 8. IANA Considerations IANA assigns values to RSVP-TE objects (see [RFC-3209]) and CR-LDP (see [RFC-3212]). Two C-Type values have to be assigned by IANA for the following RSVP objects: - G.709 SENDER_TSPEC object: Class = 12, C-Type = TBA (see Section 6.1). - G.709 FLOWSPEC object: Class = 9, C-Type = TBA (see Section 6.1). This draft also uses the LDP [RFC 3031] name spaces, which require assignment of the Type field for the following TLV: - G.709 Traffic Parameters TLV (see section 6.2). 9. Acknowledgments The authors would like to thank Jean-Loup Ferrant, Mathieu Garnot, Massimo Canali, Germano Gasparini and Fong Liaw for their constructive comments and inputs as well as James Fu, Siva Sankaranarayanan and Yangguang Xu for their useful feedback. This draft incorporates (upon agreement) material and ideas from draft-lin-ccamp-ipo-common-label-request-00.txt. 10. Intellectual Property Notice The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication 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 implementors or users of this specification can be obtained from the IETF Secretariat. D.Papadimitriou et al. - Internet Draft û Expires May 2003 15 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. 11. References 11.1 Normative References [ITUT-G707] ITU-T G.707 Recommendation, æNetwork node interface for the synchronous digital hierarchy (SDH)Æ, ITU-T, October 2000. [ITUT-G709] ITU-T G.709 Recommendation, version 1.0 (and Amendment 1), æInterface for the Optical Transport Network (OTN)Æ, ITU-T, February 2001 (and October 2001). [ITUT-G798] ITU-T G.798 Recommendation, version 1.0, æCharacteristics of Optical Transport Network Hierarchy Equipment Functional BlocksÆ, ITU-T, October 2001. [ITUT-G872] ITU-T G.872 Recommendation, version 2.0, æArchitecture of Optical Transport NetworkÆ, ITU-T, October 2001. [GMPLS-ARCH] E.Mannie (Editor) et al., æGeneralized Multi-Protocol Label Switching (GMPLS) ArchitectureÆ, Internet Draft, Work in progress, draft-ietf-ccamp-gmpls-architecture- 03.txt, August 2002. [GMPLS-LDP] L.Berger (Editor) et al., æGeneralized MPLS Signaling - CR-LDP ExtensionsÆ, Internet Draft, Work in progress, draft-ietf-mpls-generalized-cr-ldp-07.txt, August 2002. [GMPLS-RSVP] L.Berger (Editor) et al., æGeneralized MPLS Signaling - RSVP-TE ExtensionsÆ, Internet Draft, Work in progress, draft-ietf-mpls-generalized-rsvp-te-09.txt, October 2002. [GMPLS-RTG] K.Kompella et al., æRouting Extensions in Support of Generalized MPLSÆ, Internet Draft, Work in Progress, draft-ietf-ccamp-gmpls-routing-05.txt, September 2002. [GMPLS-SIG] L.Berger (Editor) et al., æGeneralized MPLS - Signaling Functional DescriptionÆ, Internet Draft, Work in progress, draft-ietf-mpls-generalized- signaling-09.txt, August 2002. [GMPLS-SONET-SDH] E.Mannie and D.Papadimitriou (Editors) et al., æGeneralized Multiprotocol Label Switching Extensions for SONET and SDH ControlÆ, Internet Draft, Work in progress, draft-ietf-ccamp-gmpls-sonet-sdh-07.txt, October 2002. D.Papadimitriou et al. - Internet Draft û Expires May 2003 16 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 [RFC-2119] S.Bradner, "Key words for use in RFCs to Indicate Requirement Levels," RFC 2119. [RFC-2205] R.Braden et al., "Resource ReSerVation Protocol (RSVP) -- Version 1 Functional Specification", RFC 2205, September 1997. [RFC-2210] J.Wroclawski, æThe Use of RSVP with IETF Integrated ServicesÆ, Internet RFC 2210, IETF Standard Track, September 1997. [RFC-3036] L.Andersson et al., æLDP SpecificationÆ, Internet RFC 3036, IETF Proposed Standard, January 2001. [RFC-3209] D.Awduche et al., æRSVP-TE: Extensions to RSVP for LSP TunnelsÆ, Internet RFC 3209, IETF Proposed Standard, December 2001. [RFC-3212] B.Jamoussi (Editor) et al. æConstraint-Based LSP Setup using LDPÆ, Internet RFC 3212, IETF Proposed Standard, January 2002. 12. Contributors Alberto Bellato (Alcatel) Via Trento 30, I-20059 Vimercate, Italy Phone: +39 039 686-7215 Email: alberto.bellato@netit.alcatel.it Sudheer Dharanikota (Nayna Networks) 157 Topaz Street, Milpitas, CA 95035, USA Phone: +1 408 956-8000X357 Email: sudheer@nayna.com Michele Fontana (Alcatel) Via Trento 30, I-20059 Vimercate, Italy Phone: +39 039 686-7053 Email: michele.fontana@netit.alcatel.it Nasir Ghani (Sorrento Networks) 9990 Mesa Rim Road, San Diego, CA 92121, USA Phone: +1 858 646-7192 Email: nghani@sorrentonet.com Gert Grammel (Alcatel) Via Trento 30, I-20059 Vimercate, Italy Phone: +39 039 686-4453 D.Papadimitriou et al. - Internet Draft û Expires May 2003 17 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 Email: gert.grammel@netit.alcatel.it Dan Guo (Turin Networks) 1415 N. McDowell Blvd, Petaluma, CA 94954, USA Phone: +1 707 665-4357 Email: dguo@turinnetworks.com Juergen Heiles (Siemens AG) Hofmannstr. 51, D-81379 Munich, Germany Phone: +49 897 224-8664 Email: juergen.heiles@icn.siemens.de Jim Jones (Alcatel) 3400 W. Plano Parkway, Plano, TX 75075, USA Phone: +1 972 519-2744 Email: Jim.D.Jones1@usa.alcatel.com Zhi-Wei Lin (Lucent) 101 Crawfords Corner Rd, Rm 3C-512 Holmdel, New Jersey 07733-3030, USA Tel: +1 732 949-5141 Email: zwlin@lucent.com Eric Mannie (KPNQwest) Terhulpsesteenweg, 6A, 1560 Hoeilaart, Belgium Phone: +32 2 658-5652 Email: eric.mannie@ebone.com Maarten Vissers (Lucent) Boterstraat 45, Postbus 18, 1270 AA Huizen, Netherlands Email: mvissers@lucent.com Yong Xue (WorldCom) 22001 Loudoun County Parkway, Ashburn, VA 20147, USA Tel: +1 703 886-5358 Email: yong.xue@wcom.com 13. AuthorÆs Address Dimitri Papadimitriou (Alcatel) Francis Wellesplein 1, B-2018 Antwerpen, Belgium Phone: +32 3 240-8491 Email: dimitri.papadimitriou@alcatel.be D.Papadimitriou et al. - Internet Draft û Expires May 2003 18 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 Appendix 1 û Abbreviations BSNT Bit Stream without Octet Timing BSOT Bit Stream with Octet Timing CBR Constant Bit Rate ESCON Enterprise Systems Connection FC Fiber Channel FEC Forward Error Correction FICON Fiber Connection FSC Fiber Switch Capable GCC General Communication Channel GFP Generic Framing Procedure LSC Lambda Switch Capable LSP Label Switched Path MS Multiplex Section naOH non-associated Overhead NMC Number of Multiplexed Components NVC Number of Virtual Components OCC Optical Channel Carrier OCG Optical Carrier Group OCh Optical Channel (with full functionality) OChr Optical Channel (with reduced functionality) ODTUG Optical Date Tributary Unit Group ODU Optical Channel Data Unit OH Overhead OMS Optical Multiplex Section OMU Optical Multiplex Unit OOS OTM Overhead Signal OPS Optical Physical Section OPU Optical Channel Payload Unit OSC Optical Supervisory Channel OTH Optical Transport Hierarchy OTM Optical Transport Module OTN Optical Transport Network OTS Optical Transmission Section OTU Optical Channel Transport Unit OTUkV Functionally Standardized OTUk PPP Point to Point Protocol PSC Packet Switch Capable RES Reserved RS Regenerator Section TTI Trail Trace Identifier TDM Time Division Multiplex Appendix 2 û G.709 Indexes - Index k: The index "k" is used to represent a supported bit rate and the different versions of OPUk, ODUk and OTUk. k=1 represents an approximate bit rate of 2.5 Gbit/s, k=2 represents an approximate bit rate of 10 Gbit/s, k = 3 an approximate bit rate of 40 Gbit/s and k = 4 an approximate bit rate of 160 Gbit/s (under definition). The exact bit-rate values are in kbits/s: . OPU: k=1: 2 488 320.000, k=2: 9 995 276.962, k=3: 40 150 519.322 D.Papadimitriou et al. - Internet Draft û Expires May 2003 19 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 . ODU: k=1: 2 498 775.126, k=2: 10 037 273.924, k=3: 40 319 218.983 . OTU: k=1: 2 666 057.143, k=2: 10 709 225.316, k=3: 43 018 413.559 - Index m: The index "m" is used to represent the bit rate or set of bit rates supported on the interface. This is a one or more digit ôkö, where each ôkö represents a particular bit rate. The valid values for m are (1, 2, 3, 12, 23, 123). - Index n: The index "n" is used to represent the order of the OTM, OTS, OMS, OPS, OCG and OMU. This index represents the maximum number of wavelengths that can be supported at the lowest bit rate supported on the wavelength. It is possible that a reduced number of higher bit rate wavelengths are supported. The case n=0 represents a single channel without a specific wavelength assigned to the channel. - Index r: The index "r", if present, is used to indicate a reduced functionality OTM, OCG, OCC and OCh (non-associated overhead is not supported). Note that for n=0 the index r is not required as it implies always reduced functionality. D.Papadimitriou et al. - Internet Draft û Expires May 2003 20 draft-ietf-ccamp-gmpls-g709-03.txt November 2002 Full Copyright Statement "Copyright (C) The Internet Society (date). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE." D.Papadimitriou et al. - Internet Draft û Expires May 2003 21