Network Working Group A. Retana Internet-Draft Cisco Systems, Inc. Intended status: Standards Track A. Weher Expires: April 27, 2015 TelVGG October 24, 2014 Use of the Cost Community to Propagate BGP Origin Validation State draft-retana-sidr-origin-validation-cost-community-00 Abstract This document explains the use of the Cost Community to provide flexibility in the application of routing policy related to the origin validation state of a route. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on April 27, 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 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. Retana & Weher Expires April 27, 2015 [Page 1] Internet-Draft Cost Community for BGP Origin Validation October 2014 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 2 3. Use of the Cost Community to Propagate BGP Origin Validation State . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 4. Operational Considerations . . . . . . . . . . . . . . . . . 3 5. Security Considerations . . . . . . . . . . . . . . . . . . . 3 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 3 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 4 8.1. Normative References . . . . . . . . . . . . . . . . . . 4 8.2. Informative References . . . . . . . . . . . . . . . . . 4 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction The BGP Origin Validation mechanism [RFC6811] defines the route validation states as "Valid", "NotFound" and "Invalid". The Origin Validation State Extended Community [I-D.ietf-sidr-origin-validation-signaling] has been defined so that this state can be considered prior to any of the steps defined in the BGP decision process [RFC4271]. It has been suggested that the LOCAL_PREF attribute [RFC4271] may also be used to indicate the degree of preference of a route according to its origin validation state. [RFC7115] also suggests the need to consider the origin validation state at other steps in the selection process, for example after considering the AS_PATH length. The Cost Community [I-D.ietf-idr-custom-decision] can provide a flexible mechanism to propagate the origin validation state, without overloading existing attributes that may already be used to set other types of local policy (such as the LOCAL_PREF). 2. 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 [RFC2119]. 3. Use of the Cost Community to Propagate BGP Origin Validation State It is RECOMMENDED that the values defined in [I-D.ietf-sidr-origin-validation-signaling] also be used to assign the Cost: Retana & Weher Expires April 27, 2015 [Page 2] Internet-Draft Cost Community for BGP Origin Validation October 2014 +------+------------------+ | Cost | Validation State | +------+------------------+ | 0 | Valid | | 1 | NotFound | | 2 | Invalid | +------+------------------+ Cost vs Validation State The Point of Insertion (POI) can be set to any of the values defined in [I-D.ietf-idr-custom-decision]. Note that the use of the ABSOLUTE_VALUE POI is equivalent to using the Origin Validation State Extended Community. If the Cost Community is used to propagate the origin validation state, then the Origin Validation State Extended Community SHOULD NOT be used. If used, then it will always take precendence over the Cost Community, regardless of the POI used. 4. Operational Considerations The use of the origin validation state as part of the BGP decision process is a matter of local policy. The policy mechanism chosen to propagate the origin validation state SHOULD be implemented uniformly across the local autonomous system to guarantee a consistent decision process and reduce the risk of routing loops. 5. Security Considerations This document explains the use of the Cost Community to provide flexibility in the application of routing policy related to the origin validation state of a route. As such, it does not introduce new security risks beyond the ones considered in [I-D.ietf-idr-custom-decision] or [RFC6811]. 6. IANA Considerations This document has no IANA actions. 7. Acknowledgements The authors would like to thank Keyur Patel. Retana & Weher Expires April 27, 2015 [Page 3] Internet-Draft Cost Community for BGP Origin Validation October 2014 8. References 8.1. Normative References [I-D.ietf-idr-custom-decision] Retana, A. and R. White, "BGP Custom Decision Process", draft-ietf-idr-custom-decision-05 (work in progress), October 2014. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC6811] Mohapatra, P., Scudder, J., Ward, D., Bush, R., and R. Austein, "BGP Prefix Origin Validation", RFC 6811, January 2013. 8.2. Informative References [I-D.ietf-sidr-origin-validation-signaling] Mohapatra, P., Patel, K., Scudder, J., Ward, D., and R. Bush, "BGP Prefix Origin Validation State Extended Community", draft-ietf-sidr-origin-validation-signaling-04 (work in progress), February 2014. [RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, January 2006. [RFC7115] Bush, R., "Origin Validation Operation Based on the Resource Public Key Infrastructure (RPKI)", BCP 185, RFC 7115, January 2014. Authors' Addresses Alvaro Retana Cisco Systems, Inc. 7025 Kit Creek Rd. Research Triangle Park, NC 27709 USA Email: aretana@cisco.com Retana & Weher Expires April 27, 2015 [Page 4] Internet-Draft Cost Community for BGP Origin Validation October 2014 Ariel Weher Cooperativa Telefonica de Villa Gdor. Galvez Ltda. Av. Mitre 1028 Villa Gdor. Galvez, Santa Fe S2124HEB Argentina Email: ariel@weher.net Retana & Weher Expires April 27, 2015 [Page 5]