Network Working Group X. Fu Internet-Draft Q. Wang Intended status: Standards Track Y. Bao Expires: January 9, 2012 ZTE Corporation R. Jing X. Huo China Telecom July 8, 2011 RSVP-TE Extension for MRN/MLN Application draft-fuxh-ccamp-boundary-explicit-control-ext-03 Abstract [RFC5212] defines a Multi-Region and Multi-Layer Networks (MRN/MLN). [RFC4206] introduces a region boundary determination algorithm and a Hierarchy LSP (H-LSP) creation method. However, in some scenarios, there must be some additional information to facilitate hierarchy LSP creation. This document extends RSVP-TE to meet this requirement. 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 January 9, 2012. Copyright Notice Copyright (c) 2011 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 Fu, et al. Expires January 9, 2012 [Page 1] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 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. Conventions Used In This Document . . . . . . . . . . . . 3 2. Requirement Identification . . . . . . . . . . . . . . . . . . 3 2.1. Indication of Server Layer . . . . . . . . . . . . . . . . 3 2.2. Requirement in OTN Multi-Layer Network . . . . . . . . . . 4 2.2.1. Indication of ODUk Signal Type . . . . . . . . . . . . 4 2.2.2. Indication of Multi Stages Multiplexing Hierarchy . . 4 3. Mechanism and Protocol Extensions . . . . . . . . . . . . . . 5 3.1. Controlling FA-LSPs Boundaries . . . . . . . . . . . . . . 5 3.1.1. Boundaries Determination . . . . . . . . . . . . . . . 6 3.1.2. Example . . . . . . . . . . . . . . . . . . . . . . . 6 3.2. Explicit Route Boundary Object (ERBO) . . . . . . . . . . 7 3.2.1. Switching Capability subobject . . . . . . . . . . . . 8 3.2.2. Encoding Type subobject . . . . . . . . . . . . . . . 8 3.2.3. Signal Type subobject . . . . . . . . . . . . . . . . 9 3.2.4. Multiplexing Hierarchy subobject . . . . . . . . . . . 10 3.2.5. Signaling Procedure . . . . . . . . . . . . . . . . . 11 3.3. Exclude Route Object(XRO) . . . . . . . . . . . . . . . . 12 3.3.1. Encoding Type subobject . . . . . . . . . . . . . . . 12 3.3.2. Signal Type subobject . . . . . . . . . . . . . . . . 13 3.3.3. Multiplexing Hierarchy subobject . . . . . . . . . . . 13 4. Security Considerations . . . . . . . . . . . . . . . . . . . 14 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14 6.1. Normative References . . . . . . . . . . . . . . . . . . . 14 6.2. Informative References . . . . . . . . . . . . . . . . . . 15 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 Fu, et al. Expires January 9, 2012 [Page 2] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 1. Introduction This document describes some requirements of explicitly control Multi-Region and Multi-Layer Network. It extends mechanisms and protocols defined in [RFC4206] and [RFC6001] to meet these requirement. 1.1. 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]. 2. Requirement Identification 2.1. Indication of Server Layer [RFC4206] describes a region boundary determination algorithm and a hierarchical LSP creation method. It is well applied to multi-region network. However it isn't fully applied to multi-layer network within the same switching capability. In the following figure, three LSPs belong to the same TDM region and different latyers, but boundary node (e.g., B) could not determine that STM-N FA-LSP should be triggered according to the region boundary determination algorithm defined in [RFC4206]. The solution MUST support to explicitly indicate which server layer must be triggered. A B C D E F +---+ STM-N +---+ STM-N +----+ OTUk +----+ STM-N +---+ STM-N +---+ |VC4|-------|VC4|-------|ODUk|------|ODUk|-------|VC4|-------|VC4| +---+ +---+ +----+ +----+ +---+ +---+ |<-------------------------- VC4 LSP ------------------------->| |<------------- STM-N LSP ------------>| |<--ODUk LSP-->| Figure 1: Example of Server Layer Indication Fu, et al. Expires January 9, 2012 [Page 3] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 2.2. Requirement in OTN Multi-Layer Network 2.2.1. Indication of ODUk Signal Type In Figure 2, node B and C in the OTN network are connected to 2.5G TS network by two OTU3 links. They can support flexible multi stages multiplexing hierarchies. There are two multi stages multiplexing hierarchies for ODU0 being mapped into OTU3 link in B and C (i.e., ODU0-ODU1-ODU3 and ODU0-ODU2-ODU3). But boundary node (e.g., B) could not determine which kind of ODUk FA-LSP (ODU1, ODU2 or ODU3) should be triggered during one e2e ODU0 connection signaling according to the region boundary determination algorithm defined in [RFC4206]. If path computation entity select the ODU0-ODU2-ODU3 multi stages multiplexing hierarch in Node B and C for one end-to-end ODU0 service from A to Z, there has to be an ODU2 or ODU3 FA-LSP between B and C. The solution MUST support to explicitly indicate which type of ODUk FA-LSP must be triggered for ODUj (k>j). 3/1/0 2/0 3/2/0 | _______ | ___ _|_____ / \ _|_____ ___ | A | | | B | | 40G | | | C | | Z | | o-|-----------|-o o-|----| Network |----|-o o-|-----------|-o | |___| OTU2 Link |_____|_|OTU3|(2.5G TS)|OTU3|_____|_| OTU2 Link |___| (1.25G TS) | \_______/ | (1.25G TS) | | 0/1/3 0/2 0/2/3 Figure 2 Example of ODUk Signal Type Indication 2.2.2. Indication of Multi Stages Multiplexing Hierarchy In figure 2, if ODU3 FA-LSP will be triggered between B and C to directly support one end-to-end ODU0 service from A to Z, B should be informed which multi stages multiplexing hierarchy should be used for ODU0 mapping into ODU3. So the solution MUST support to explicitly indicate which multi stages multiplexing hierarchy must be applied to a special interface. Fu, et al. Expires January 9, 2012 [Page 4] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 3. Mechanism and Protocol Extensions This section defines protocol mechanisms and extensions to achieve the requirement described in the previous section. o A generic boundaries determination mechanism is introduced first. Path computation entity or interim LSR along one end-to-end LSP which traverses multi-layer can rely on this mechnism to determine the boundary nodes of FA-LSP. o Path computation entity can determine regions' boundaries. After PCE compute an end-to-end paths across multi-layer, the boundary nodes and some limitation about how to create FA-LSP must be inform to interim nodes during signaling. A new object, Explicit Route Boundary Object(ERBO), is introduced to explicitly indicate a pair of FA-LSP boundary nodes and some attributes which indicates how to create FA-LSPs. This document also introduces some new subobjects as part of the XRO that explicitly indicate which Signal Type, Multiplexing Hierarchy and Encoding Type have to be excluded before initiating FA-LSP creation. 3.1. Controlling FA-LSPs Boundaries The boundary determination mechanism in [RFC4206] depends on the comparing of interface switching capabilities. For multi-layer network within the same TDM switching capability, the comparing of interface switching capabilities relies on the max LSP bandwidth of interface. But one interface in OTN netowrk could support several ODUk signal type, the max LSP bandwidth makes no any sense to path computation entity. The mechanism in [RFC4206] isn't well applied to OTN multi-layer network. The solution MUST support the boundaries determination of ODUk FA-LSP. This document introduces a generic mechanism to determine the boundaries of FA-LSPs by using termination and switching capability from IGP database. It can be applied to multi-layer network within same switching capability (e.g, OTN network) and multi-region network. So this mechanism is compatible with the one in [RFC4206]. The switching and termination capability could be induced by IACD [RFC6001] in multi-regin network. In OTN multi-layer network, the switching and termiantion Capability [OTNv3-OSPF] is advertised by using SCSI (Switch Capability Specific Information) within ISCD. Fu, et al. Expires January 9, 2012 [Page 5] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 3.1.1. Boundaries Determination Suppose an LSP's path is as follows: node-0, link-1, node-1, link-2, node-2, ..., link-n, node-n. Moreover, for link-i denote by [link-i, node-(i-1)] the interface that connects link-i to node-(i-1), and by [link-i, node-i] the interface that connects link-i to node-i. Suppose interface [link-(i+1), node-i] supports switching capability of one signal type ST-x and termination capability of one signal type ST-y. Interface [link-(i+1), node-(i+1)] supports switiching capability of ST-y. Switching capability of ST-y (e.g., LSC) is larger than ST-x (e.g., TDM/G.709) or ST-x (e.g., ODUj) could be mapped into ST-y (e.g., ODUk (k>j)). So we say that the LSP has crossed a region boundary at node-i. The 'other edge' of the region with respect to the LSP path is node-k, where k is the smallest number greater than i such that interface [link-k, node-(k-1)] supports switching capability of ST-y and interface [link-k, node-k] suuports switching capability of ST-x and termination capability of ST-y. 3.1.2. Example A multi-layer OTN network is illustrated in figure 3. Node B and D support ODUj being mapping into ODUk (k>j). Interface IF-B and IF-D support ODUj switching capability (ODUj(S)) and ODUk termination capability (ODUk(T)). Interface within C only supports ODUk switching capability. So Node B and D could be boundaries of ODUk FA-LSP for ODUj LSP. ODUj(S) ODUj(S) ODUk(S) ODUk(S) ODUj(S) | | | | | | __|_ _|___ _|_|_ ___|_ _|___ | A| | | |B | | | | | | D| | | |E | ...---|o o-|----|-o o-|----|-o o-|----|-o o-|----|-o o-|---... |____| |___|_| |__C__| |_|___| |_____| | | |IF-B IF-D | | | ODUj(S)-- --ODUj(S) \ / | | ODUk(T)<-/ \->ODUk(T) Figure 3 Example of Controlling ODUk FA-LSPs Boundaries Fu, et al. Expires January 9, 2012 [Page 6] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 A multi-region network is illustrated in figure 4. Node B and D which are hybrid nodes support PSC being mapping into ODUk (e.g., by GFP-F). Interface IF-B and IF-D support PSC switching capability (PSC(S)) and ODUk termination capability (ODUk(T)). Interface within C only supports ODUk switching capability. So Node B and D could be boundaries of ODUk FA-LSP for PSC LSP. PSC(S) PSC(S) ODUk(S) PSC(S) PSC(S) | | | | | | __|_ _|___ | | ___|_ _|___ | A| | | |B | _|_|_ | | | | | ...---|o o-|----|-o | | | | | | o-|----|-o o-|---... |____| | o-|----|-o o-|----|-o | |_____| |___|_| |_____| |_|___| | | |IF-B IF-D| | | PSC-ODUk IACD PSC-ODUK IACD Figure 4 Example of Controlling ODUk FA-LSPs Boundaries 3.2. Explicit Route Boundary Object (ERBO) In order to explicitly control hierarchy LSP creation, this document introduce a new object (ERBO-Explicit Route Boundary Object) carried in Path message. The format of ERBO object is the same as ERO. It looks more like the SERO defined in [RFC4873]. One or more ERBOs may be carried in Path message. Multiple ERBOs could support cascading of FA easy. An ERBO must contain at least two subobjects. The first and final one indicate the source and sink node of a FA-LSP or Composite Link [CL-REQ] which will be passed by one e2e LSP. Other subobjects may be inserted into ERBO between source and sink node to indicates how to select the FA/Component Link or create them. The purpose is not to extend ERO and to limit the modifications to existing RSVP-TE procedures. ERBO is a top object and parsed easy. Many attributes could be inserted into ERBO in the future for other requirements. This document defines four subobjects (i.e., Switching Cap, Encoding Type, Signal Type and Multiplexing Hierarchy) in ERBO. These subobjects may be inserted into ERBO between source and sink node to indicates how to select the FA/Component Link or create them. It is very convenient to use these subobects independently or combine them. Fu, et al. Expires January 9, 2012 [Page 7] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 For example, Signal Type and Multiplexing Hierarchy subobject are enough for OTN multi-layer network application. 3.2.1. Switching Capability subobject A new subobject, called the switching capability subobject, is defined for use in the ERBO. The format of the switching capability subobject 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |L| Type | Length | Reserved | Switching Cap | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 5 Switching Capability subobject in ERBO o L-bit: 0 indicates that the attribute specified MUST be included. 1 indicates that the attribute specified SHOULD be included. o Type: To be defined. o Length: It is always 4. o Switching Capability (SC): Indicates which corresponding server layer should be triggered by the boundary node. The value of switching capability is the same as the one in [RFC3471]. 3.2.2. Encoding Type subobject A new subobject, called the encoding type subobject, is defined for use in the ERBO. The format of the encoding type subobject 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |L| Type | Length | Reserved | Encoding Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 6 Encoding Type subobject in ERBO o L-bit: 0 indicates that the attribute specified MUST be included. 1 indicates that the attribute specified SHOULD be included. Fu, et al. Expires January 9, 2012 [Page 8] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 o Type: To be defined. o Length: It is always 4. o Encoding Type: It may need to further indicate which encoding type (e.g., SDH/SONET or G.709 in TDM) should be triggered. It is the same as the one in [RFC3471]. 3.2.3. Signal Type subobject A new subobject, called the signal type subobject, is defined for use in the ERBO. The format of the encoding type subobject 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |L| Type | Length | Reserved | Signal Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 7 Signal Type subobject in ERBO o L-bit: 0 indicates that the attribute specified MUST be included. 1 indicates that the attribute specified SHOULD be included. o Type: To be defined. o Length: It is always 4. o Signal Type: If there are several sub-layers within one server layer, it can further indicates which sub-layer should be triggered by the boundary node. Following is the signal type in OTN. Fu, et al. Expires January 9, 2012 [Page 9] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 Value Type ----- ---- 0 Not significant 1 ODU1 2 ODU2 3 ODU3 4 ODU4 5 ODU0 6 ODUflex 7 ODUflex(G.hao) 8 ODU2e 9 STM-1 10 STM-4 11 STM-16 12 STM-64 13-255 Reserved (for future use) 3.2.4. Multiplexing Hierarchy subobject A new subobject, called the Multiplexing Hierarchy (MH) subobject, is defined for use in the ERBO. The format of the multiplexing hierarchy subobject 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |L| Type | Length | Reserved | MH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 8 Multiplexing Hierarchy subobject in ERBO o L-bit: 0 indicates that the attribute specified MUST be included. 1 indicates that the attribute specified SHOULD be included. o Type: To be defined. o Length: It is always 4. o Multiplexing Hierarchy (MH): It explicitly indicates the multiplexing hierarchy used for boundary node to configure it to the data plane and trigger one specific corresponding tunnel creation. Following is the multiplexing hierarchy in current OTN. Fu, et al. Expires January 9, 2012 [Page 10] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 Value Type ----- ------ 0 ODU1-ODU0 1 ODU2-ODU0 2 ODU2-ODU1 3 ODU2-ODU1-ODU0 4 ODU2-ODUflex 5 ODU3-ODU0 6 ODU3-ODU1 7 ODU3-ODU1-ODU0 8 ODU3-ODU2 9 ODU3-ODU2-ODU0 10 ODU3-ODU2-ODU1 11 ODU3-ODU2-ODU1-ODU0 12 ODU3-ODU2-ODUflex 13 ODU3-ODUflex 14 ODU3-ODU2e 15 ODU4-ODU0 16 ODU4-ODU1 17 ODU4-ODU1-ODU0 18 ODU4-ODU2 19 ODU4-ODU2-ODU0 20 ODU4-ODU2-ODU1 21 ODU4-ODU2-ODU1-ODU0 22 ODU4-ODU2-ODUflex 23 ODU4-ODU3 24 ODU4-ODU3-ODU0 25 ODU4-ODU3-ODU1 26 ODU4-ODU3-ODU1-ODU0 27 ODU4-ODU3-ODU2 28 ODU4-ODU3-ODU2-ODU0 29 ODU4-ODU3-ODU2-ODU1 30 ODU4-ODU3-ODU2-ODU1-ODU0 31 ODU4-ODU3-ODU2-ODUflex 32 ODU4-ODU3-ODUflex 33 ODU4-ODU3-ODU2e 34 ODU4-ODUflex 35 ODU4-ODU2e 3.2.5. Signaling Procedure In order to signal an end-to-end LSP across multi layer, the LSP source node sends the RSVP-TE PATH message with ERO which indicates LSP route and ERBO which indicates the LSP route boundary If. if there are cascading FAs need to be created, there must be multiple associated ERBOs. There must be nesting routing informatoin in ERO. The first and final address of node in ERBO SHOULD also be listed in the ERO. This ensures that they are along the LSP path. When a Fu, et al. Expires January 9, 2012 [Page 11] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 interim node receives a PATH message, it will check ERBO to see if it is the layer boundary node. If a interim node isn't a layer boundary, it will process the PATH message as the normal one of single layer LSP. If a interim node finds its address is in ERBO, it is a layer boundary node. So it will directly extract another boundary egress node from ERBO. If it is necessary, it must also extract the server layer/sub-layer routing information from ERO based on a pair of boundary node. Then the layer boundary node holds the PATH message and selects or creates a server layer/sub-layer LSP based on the detailed information of subobject carried in ERBO. 3.3. Exclude Route Object(XRO) [RFC6001] introduce SC (Switching Capability) subobjects into XRO [RFC4874] which enables (when desired) the explicit identification of at least one switching capability to be excluded from the resource selection process described multi-region signaling. This document adds more subobjects into the XRO to make multi-region and multi- layer signaling more flexible. o Encoding Type: explicitly indicates the encoding type should be excluded (e.g., SONET/SDH or G.709 in TDM). o Signal Type (ST) : explicitly indicates at least one ODUk signal type have to be excluded from the resource selection. o Multiplexing Hierarchy (MH): explicitly indicates at least one MH have to be excluded from the resource selection. L bit and Attribute is the same as the Switching Capability (SC) subobject defined in [RFC6001]. 3.3.1. Encoding Type subobject A new subobject, called the encoding type subobject, is defined for use in the XRO. The format of the encoding type subobject 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |L| Type | Length | Attribute | Encoding Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 9 Encoding Type subobject in XRO Fu, et al. Expires January 9, 2012 [Page 12] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 o L-bit: 0 indicates that the attribute specified MUST be excluded. 1 indicates that the attribute specified SHOULD be avoided. o Type: To be defined. o Length: It is always 4. o Attribute: 0 reserved value. 1 indicates that the specified encoding type SHOULD be excluded or avoided with respect to the preceding numbered or unnumbered interface subobject. o Encoding Type: It indicates which Encoding Type has to excluded. It is the same as the one in [RFC3471]. 3.3.2. Signal Type subobject A new subobject, called the signal type subobject, is defined for use in the XRO. The format of the encoding type subobject 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |L| Type | Length | Attribute | Signal Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 10 Signal Type subobject in XRO o L-bit: 0 indicates that the attribute specified MUST be excluded. 1 indicates that the attribute specified SHOULD be avoided. o Type: To be defined. o Length: It is always 4. o Attribute: 0 reserved value. 1 indicates that the specified signal type SHOULD be excluded or avoided with respect to the preceding numbered or unnumbered interface subobject. o Signal Type: It indicates which Signal Type has to be excluded. The value of ST is the same as the one in ERBO. 3.3.3. Multiplexing Hierarchy subobject A new subobject, called the Multiplexing Hierarchy (MH) subobject, is defined for use in the XRO. The format of the multiplexing hierarchy subobject is defined as follows: Fu, et al. Expires January 9, 2012 [Page 13] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |L| Type | Length | Attribute | MH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 11 Multiplexing Hierarchy subobject in XRO o L-bit: 0 indicates that the attribute specified MUST be excluded. 1 indicates that the attribute specified SHOULD be avoided. o Type: To be defined. o Length: It is always 4. o Attribute: 0 reserved value. 1 indicates that the specified multiplexing hierarchy SHOULD be excluded or avoided with respect to the preceding numbered or unnumbered interface subobject. o Multiplexing Hierarchy (MH): It explicitly indicates which MH has to be excluded over a specified TE link, The value of multiplexing hierarchy is the same as the one in ERBO. 4. Security Considerations This document does not introduce any new security considerations from the ones already detailed in [RFC5920] that describes the MPLS and GMPLS security threats, the related defensive techniques, and the mechanisms for detection and reporting. 5. IANA Considerations TBD 6. References 6.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", RFC 3209, December 2001. Fu, et al. Expires January 9, 2012 [Page 14] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 [RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) Signaling Functional Description", RFC 3471, January 2003. [RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) Signaling Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Extensions", RFC 3473, January 2003. [RFC4203] Kompella, K. and Y. Rekhter, "OSPF Extensions in Support of Generalized Multi-Protocol Label Switching (GMPLS)", RFC 4203, October 2005. [RFC4206] Kompella, K. and Y. Rekhter, "Label Switched Paths (LSP) Hierarchy with Generalized Multi-Protocol Label Switching (GMPLS) Traffic Engineering (TE)", RFC 4206, October 2005. [RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation Element (PCE)-Based Architecture", RFC 4655, August 2006. [RFC5212] Shiomoto, K., Papadimitriou, D., Le Roux, JL., Vigoureux, M., and D. Brungard, "Requirements for GMPLS-Based Multi- Region and Multi-Layer Networks (MRN/MLN)", RFC 5212, July 2008. [RFC5440] Vasseur, JP. and JL. Le Roux, "Path Computation Element (PCE) Communication Protocol (PCEP)", RFC 5440, March 2009. 6.2. Informative References [CL-REQ] C. Villamizar, "Requirements for MPLS Over a Composite Link", draft-ietf-rtgwg-cl-requirement-04 . [OTNv3-OSPF] D. Ceccarelli, "Traffic Engineering Extensions to OSPF for Generalized MPLS (GMPLS) Control of Evolving G.709 OTN Networks", draft-ceccarelli-ccamp-gmpls-ospf-g709-06 . Authors' Addresses Xihua Fu ZTE Corporation Email: fu.xihua@zte.com.cn Fu, et al. Expires January 9, 2012 [Page 15] Internet-Draft RSVP-TE for Hierarchy LSP Control July 2011 Qilei Wang ZTE Corporation Email: wang.qilei@zte.com.cn Yuanlin Bao ZTE Corporation Email: bao.yuanlin@zte.com.cn Ruiquan Jing China Telecom Email: jingrq@ctbri.com.cn Xiaoli Huo China Telecom Email: huoxl@ctbri.com.cn Fu, et al. Expires January 9, 2012 [Page 16]