TEAS C. Margaria, Ed. Internet-Draft Juniper Intended status: Standards Track G. Martinelli Expires: July 3, 2015 Cisco S. Balls B. Wright Metaswitch December 30, 2014 LSP Attribute in ERO draft-ietf-teas-lsp-attribute-ro-01 Abstract RFC5420 extends RSVP-TE to specify or record generic attributes which apply to the whole of the path of an LSP. This document proposes an extension to the RSVP ERO and RRO objects to allow it to specify or record generic attributes which apply to a given hop. 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 July 3, 2015. Copyright Notice Copyright (c) 2014 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 Margaria, et al. Expires July 3, 2015 [Page 1] Internet-Draft General ERO LSP parameters December 2014 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 . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 2. ERO Hop Attributes Subobject . . . . . . . . . . . . . . . . 3 2.1. Encoding . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2. HOP Attributes TLVs . . . . . . . . . . . . . . . . . . . 4 2.3. Procedures . . . . . . . . . . . . . . . . . . . . . . . 4 3. RRO Hop Attributes Subobject . . . . . . . . . . . . . . . . 5 3.1. Encoding . . . . . . . . . . . . . . . . . . . . . . . . 5 3.2. Procedures . . . . . . . . . . . . . . . . . . . . . . . 5 3.2.1. Subobject presence rule . . . . . . . . . . . . . . . 5 3.2.2. Reporting Compliance with ERO Hop Attributes . . . . 6 3.2.3. Compatibility with RRO Attributes subobject . . . . . 6 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 4.1. ERO LSP Attribute Subobject . . . . . . . . . . . . . . . 6 4.2. RRO LSP Attribute Subobject . . . . . . . . . . . . . . . 7 4.3. Existing LSP Attribute TLVs . . . . . . . . . . . . . . . 7 5. Security Considerations . . . . . . . . . . . . . . . . . . . 8 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 8 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 7.1. Normative References . . . . . . . . . . . . . . . . . . 8 7.2. Informative References . . . . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 1. Introduction Generalized MPLS (GMPLS) Traffic Engineering (TE) Label Switched Paths (LSPs) can be route-constrained by making use of the Explicit Route object (ERO) and related sub-objects as defined in [RFC3209], [RFC3473], [RFC3477], [RFC4873], [RFC4874], [RFC5520] and [RFC5553]. Several documents have identified the need for attributes that can be targeted at specific hops in the path of an LSP, including [RFC6163], [I-D.ietf-ccamp-wson-signaling], [I-D.ietf-teas-rsvp-te-li-lb] or [I-D.ali-ccamp-rc-objective-function-metric-bound]. This document provides a generic mechanism for use by these other documents. RSVP already supports generic extension of LSP Attributes in [RFC5420]. In order to support current and future ERO constraint extensions this document defines a mechanism to define per-Hop attributes. The document describes a generic mechanism for carrying information related to specific nodes when signaling an LSP. This document does Margaria, et al. Expires July 3, 2015 [Page 2] Internet-Draft General ERO LSP parameters December 2014 not restrict what that information can be used for. The defined approach builds on LSP Attributes defined in [RFC5420], and enables attributes to be expressed in ERO and Secondary Explicit Route object (SERO) objects. A new ERO sub-object is defined, containing a list of generic per-Hop attributes. 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. ERO Hop Attributes Subobject The ERO Hop Attributes subobject may be carried in the ERO or SERO object if they are present. The subobject uses the standard format of an ERO subobject. 2.1. Encoding The length is variable and content is a list of HOP Attributes TLVs defined in Section 2.2. The size of the ERO sub-object limits the size of the attribute TLV to 250 bytes. The typical size of currently defined and forthcoming LSP_ATTRIBUTE TLVs applicable to a specific hop (WSON_SIGNALING, Objective Function (OF) and Metric) is not foreseen to exceed this limit. The ERO Hop Attributes 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 |R| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // Attributes TLVs // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The L, Type and Length parameters are as defined in [RFC3209] section 4.3.3. The L bit MUST be set to 0. The Type for the ERO Hop Attributes subobject is TBA by IANA. The attributes TLV are encoded as defined in section Section 2.2. Reserved Reserved, MUST be set to 0 when the subobject is inserted in the ERO, MUST NOT be changed when a node processes the ERO and Margaria, et al. Expires July 3, 2015 [Page 3] Internet-Draft General ERO LSP parameters December 2014 MUST be ignored on the node addressed by the preceding ERO subobjects. R This bit reflects the LSP_REQUIRED_ATTRIBUTE and LSP_ATTRIBUTE semantic defined in [RFC5420]. When set it indicates required hop attributes to be processed by the node. When cleared, it indicates that the hop attributes are not required as described in Section Section 2.3. Attributes TLVs as defined in Section 2.2 . 2.2. HOP Attributes TLVs ERO Attributes carried by the new objects defined in this document are encoded within TLVs. One or more TLVs MAY be present in each object. There are no ordering rules for TLVs, and interpretation SHOULD NOT be placed on the order in which TLVs are received. The TLV format is defined in [RFC5420] section 3. 2.3. Procedures As described in [RFC3209] and [RFC3473] the ERO is managed as a list where each hop information starts with a subobject identifying an abstract node or link. The ERO Hop Attributes subobject MUST be appended after the existing subobjects defined in [RFC3209], [RFC3473], [RFC3477], [RFC4873], [RFC4874], [RFC5520] and [RFC5553]. Several ERO Hop Attributes subobject MAY be present, for each hop. If a node is processing an ERO Hop Attributes subobject and does not support handling of the subobject it will behave as described in [RFC3209] when an unrecognized ERO subobject is encountered. This node will return a PathErr with error code "Routing Error" and error value "Bad EXPLICIT_ROUTE object" with the EXPLICIT_ROUTE object included, truncated (on the left) to the offending unrecognized subobject. When the R bit is set a node MUST examine the attribute TLV present in the subobject following the rules described in [RFC5420] section 5.2. When the R bit is not set a node MUST examine the attribute TLV present in the subobject following the rules described in [RFC5420] section 4.2. A node processing an ERO Hop Attributes subobject with an HOP Attributes TLV longer than the ERO subobject SHOULD return a PathErr with error code "Routing Error" and error value "Bad EXPLICIT_ROUTE object" with the EXPLICIT_ROUTE object included, truncated (on the left) to the offending malformed subobject. A processing node MUST NOT originates a HOP Attributes TLV longer than the ERO HOP Margaria, et al. Expires July 3, 2015 [Page 4] Internet-Draft General ERO LSP parameters December 2014 Attributes Subobject. The processing of the Hop attribute TLVs SHOULD be described in the documents defining them. 3. RRO Hop Attributes Subobject In some cases it is important to determine if an optional Hop attribute has been processed by a node. 3.1. Encoding The RRO Hop Attributes subobject may be carried in the RECORD_ROUTE object if it is present. The subobject uses the standard format of an RRO subobject. The RRO Hop Attributes 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // Attributes TLVs // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The Type and Length parameters are as defined in [RFC3209] section 4.4.1. The Type for the RRO Hop Attributes subobject is TBA by IANA. The attributes TLV are encoded as defined in section Section 2.2. Reserved Reserved, must be set to 0 when the subobject is inserted in the RRO, MUST NOT be changed when a node process the RRO and must be ignored on the node addressed by the preceding RRO subobjects. Attributes TLVs The processed or addition HOP Attributes, using the format defined in Section 2.2 . 3.2. Procedures 3.2.1. Subobject presence rule The RRO rules defined in [RFC3209] are not changed. The RRO Hop Attributes subobject MUST be pushed after the RRO Attributes subobject (if present) defined in in [RFC5420]. The RRO Hop Attributes subobject MAY be present between a pair of subobjects Margaria, et al. Expires July 3, 2015 [Page 5] Internet-Draft General ERO LSP parameters December 2014 identifying Label Switching Router (LSR) or links. All such subobjects MUST be forwarded unmodified by transit LSRs. 3.2.2. Reporting Compliance with ERO Hop Attributes To report that an ERO Hop attribute has been considered, or to report an additional attribute, an LSR MAY add a RRO Hop Attributes subobject with the HOP Attribute TLV which describes the attribute to be reported. The requirement to report compliance MUST be specified in the document that defines the usage of an Hop attribute. 3.2.3. Compatibility with RRO Attributes subobject The RRO Hop Attributes subobject extends the capability of the RRO Attributes subobject defined in [RFC5420] section 7.2 by allowing the node to report the attribute value. The mechanism defined in this document is compatible with the RRO Attributes subobject using the following procedures. For LSP attributes signaled in the LSP_ATTRIBUTES or LSP_REQUIRED_ATTRIBUTES objects, a node SHOULD use the RRO Attributes subobject to report processing of those attributes. For LSP attributes signaled in the ERO Hop Attributes subobject and not in the LSP_ATTRIBUTES or LSP_REQUIRED_ATTRIBUTES objects, if a node desires to report the attributes, it SHOULD use the RRO Hop Attributes subobject and SHOULD NOT use the RRO Attributes subobject. Ingress nodes not supporting the RRO Hop Attributes subobject will drop the information, as described in [RFC3209] section 4.4.5. 4. IANA Considerations 4.1. ERO LSP Attribute Subobject IANA manages the "RSVP PARAMETERS" registry located at http://www.iana.org/assignments/rsvp-parameters/rsvp-parameters.xml. We request IANA to make an allocation in the Sub-object type 20 EXPLICIT_ROUTE - Type 1 Explicit Route registry. This document introduces a new ERO sub-object: Value Description Reference ------ ----------------- ------------------------ TBA Hop Attributes This document, Section 2 Margaria, et al. Expires July 3, 2015 [Page 6] Internet-Draft General ERO LSP parameters December 2014 4.2. RRO LSP Attribute Subobject IANA manages the "RSVP PARAMETERS" registry located at http://www.iana.org/assignments/rsvp-parameters/rsvp-parameters.xml. We request IANA to make an allocation in the Sub-object type 21 ROUTE_RECORD - Type 1 Route Record registry. This document introduces a new RRO sub-object: Value Description Reference ------ ----------------- ------------------------ TBA Hop Attributes This document, Section 3 4.3. Existing LSP Attribute TLVs IANA manages the "RSVP-TE PARAMETERS" registry located at http://www.iana.org/assignments/rsvp-te-parameters/rsvp-te- parameters.xml. The "Attributes TLV Space" registry manage the following attributes, as defined in [RFC5420]: o TLV Type (T-field value) o TLV Name o Whether allowed on LSP_ATTRIBUTES object o Whether allowed on LSP_REQUIRED_ATTRIBUTES object We request IANA to add the following information for each TLV in the RSVP TLV type identifier registry. o Whether allowed on LSP Hop Attributes ERO subobject The existing registry is modified for existing TLVs as follows: The following abbreviation are used in the table: LSP_A Whether allowed on LSP_ATTRIBUTES object. LSP_RA Whether allowed on LSP_REQUIRED_ATTRIBUTES object. HOP_A Whether allowed on LSP Hop Attributes subobject. T Name LSP_A LSP_RA HOP_A Ref. - --------------------- ----- ------ ----- -------- 1 Attribute Flags Yes Yes No [RFC5420] 2 Service ID TLV Yes No No [RFC6060] 3 OAM Configuration TLV Yes Yes No [RFC7260] Margaria, et al. Expires July 3, 2015 [Page 7] Internet-Draft General ERO LSP parameters December 2014 5. Security Considerations This document adds new subobject in the EXPLICIT_ROUTE and the ROUTE_RECORD object carried in RSVP message used in MPLS and GMPLS signaling. It builds on mechanism defined in [RFC3209] and [RFC5420] and does not introduce any new security. The existing security considerations described in [RFC2205], [RFC3209], [RFC3473] and [RFC5420] do apply. As any RSVP-TE signaling request, the procedures defined in this document permit the transfer and reporting of functional preferences on specific node. This may reveal information about the LSP request and status to anyone with unauthorized access. The mechanism described in this document do not contribute to this issue, which can be only resolved by encrypting the content of the whole signaling message. In addition the reporting of attributes using the RRO may reveal details about the node that the operator wishes to remains confidential. The same strategy and policies that apply to other RRO subobjects also apply to this new mechanism. It is recommended that domain boundary policies take the releasing of RRO hop attributes into consideration. 6. Acknowledgments The authors would like to thanks Lou Berger for his directions and Attila Takacs for inspiring this [I-D.kern-ccamp-rsvpte-hop-attributes]. The authors also thanks Dirk Schroetter for his contribution to the initial versions of the documents (version -00 up to -02). 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S. Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 Functional Specification", RFC 2205, September 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. Margaria, et al. Expires July 3, 2015 [Page 8] Internet-Draft General ERO LSP parameters December 2014 [RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) Signaling Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Extensions", RFC 3473, January 2003. [RFC3477] Kompella, K. and Y. Rekhter, "Signalling Unnumbered Links in Resource ReSerVation Protocol - Traffic Engineering (RSVP-TE)", RFC 3477, January 2003. [RFC4873] Berger, L., Bryskin, I., Papadimitriou, D., and A. Farrel, "GMPLS Segment Recovery", RFC 4873, May 2007. [RFC4874] Lee, CY., Farrel, A., and S. De Cnodder, "Exclude Routes - Extension to Resource ReserVation Protocol-Traffic Engineering (RSVP-TE)", RFC 4874, April 2007. [RFC5420] Farrel, A., Papadimitriou, D., Vasseur, JP., and A. Ayyangarps, "Encoding of Attributes for MPLS LSP Establishment Using Resource Reservation Protocol Traffic Engineering (RSVP-TE)", RFC 5420, February 2009. [RFC5520] Bradford, R., Vasseur, JP., and A. Farrel, "Preserving Topology Confidentiality in Inter-Domain Path Computation Using a Path-Key-Based Mechanism", RFC 5520, April 2009. [RFC5553] Farrel, A., Bradford, R., and JP. Vasseur, "Resource Reservation Protocol (RSVP) Extensions for Path Key Support", RFC 5553, May 2009. [RFC6060] Fedyk, D., Shah, H., Bitar, N., and A. Takacs, "Generalized Multiprotocol Label Switching (GMPLS) Control of Ethernet Provider Backbone Traffic Engineering (PBB- TE)", RFC 6060, March 2011. [RFC7260] Takacs, A., Fedyk, D., and J. He, "GMPLS RSVP-TE Extensions for Operations, Administration, and Maintenance (OAM) Configuration", RFC 7260, June 2014. 7.2. Informative References [I-D.ali-ccamp-rc-objective-function-metric-bound] Ali, Z., Swallow, G., Filsfils, C., Fang, L., Kumaki, K., Kunze, R., Ceccarelli, D., and X. Zhang, "Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Extension for Signaling Objective Function and Metric Bound", draft-ali-ccamp-rc-objective-function-metric- bound-05 (work in progress), February 2014. Margaria, et al. Expires July 3, 2015 [Page 9] Internet-Draft General ERO LSP parameters December 2014 [I-D.ietf-ccamp-wson-signaling] Bernstein, G., Xu, S., Lee, Y., Martinelli, G., and H. Harai, "Signaling Extensions for Wavelength Switched Optical Networks", draft-ietf-ccamp-wson-signaling-09 (work in progress), September 2014. [I-D.ietf-teas-rsvp-te-li-lb] Dong, J., Chen, M., Li, Z., and D. Ceccarelli, "GMPLS RSVP-TE Extensions for Lock Instruct and Loopback", draft- ietf-teas-rsvp-te-li-lb-01 (work in progress), December 2014. [I-D.kern-ccamp-rsvpte-hop-attributes] Kern, A. and A. Takacs, "Encoding of Attributes of LSP intermediate hops using RSVP-TE", draft-kern-ccamp-rsvpte- hop-attributes-00 (work in progress), October 2009. [RFC6163] Lee, Y., Bernstein, G., and W. Imajuku, "Framework for GMPLS and Path Computation Element (PCE) Control of Wavelength Switched Optical Networks (WSONs)", RFC 6163, April 2011. Authors' Addresses Cyril Margaria (editor) Juniper 200 Somerset Corporate Boulevard, , Suite 4001 Bridgewater, NJ 08807 USA Email: cmargaria@juniper.net Giovanni Martinelli Cisco via Philips 12 Monza 20900 IT Phone: +39 039 209 2044 Email: giomarti@cisco.com Margaria, et al. Expires July 3, 2015 [Page 10] Internet-Draft General ERO LSP parameters December 2014 Steve Balls Metaswitch 100 Church Street Enfield EN2 6BQ GB Phone: +44 208 366 1177 Email: steve.balls@metaswitch.com Ben Wright Metaswitch 100 Church Street Enfield EN2 6BQ GB Phone: +44 208 366 1177 Email: Ben.Wright@metaswitch.com Margaria, et al. Expires July 3, 2015 [Page 11]