Network Working Group                                            R. Bush
Internet-Draft                  Internet Initiative Japan & Arrcus, Inc.
Intended status: Informational                               J. Snijders
Expires: October 23, 2020                                            NTT
                                                          April 21, 2020


Timing Parameters in the RPKI based Route Origin Validation Supply Chain
                     draft-ymbk-rpki-rov-timing-00

Abstract

   This document explores, and makes recommendations for, timing of
   Resource Public Key Infrastructure publication, propagation, and use
   of RPKI ROV data in relying parties and routers.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

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 https://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 October 23, 2020.

Copyright Notice

   Copyright (c) 2020 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



Bush & Snijders         Expires October 23, 2020                [Page 1]


Internet-Draft               RPKI ROV Timing                  April 2020


   (https://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.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Related Work  . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Deployment Structure  . . . . . . . . . . . . . . . . . . . .   3
   4.  Certification Authority Publishing  . . . . . . . . . . . . .   4
   5.  Replying Party Fetching . . . . . . . . . . . . . . . . . . .   4
   6.  Router Updating . . . . . . . . . . . . . . . . . . . . . . .   4
   7.  Alternative Technologies  . . . . . . . . . . . . . . . . . .   4
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .   5
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   5
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .   5
     10.1.  Normative References . . . . . . . . . . . . . . . . . .   5
     10.2.  Informative References . . . . . . . . . . . . . . . . .   6
   Appendix A.  Acknowledgements . . . . . . . . . . . . . . . . . .   6
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   6

1.  Introduction

   As Resource Public Key Infrastructure (RPKI) based Route Origin
   Validation (ROV) becomes deployed in the Internet, the quality of the
   routing control plane, and hence timely and accurate delivery of
   packets in the data plane, depend more and more on prompt and
   accurate propagation of the RPKI data from the originating
   Certification Authorities (CAs), to Relying Parties (RPs), to
   External Border Gateway Protocol (eBGP) speaking routers.

   Origination Validation based on stale ROAs allows accidental mis-
   origination.  While delayed ROA propagation to ROV in routers can
   cause loss of good traffic.  Though it may not be reasonable today,
   services such as DDoS cleaners would prefer that ROA publication had
   almost immediate effect on routing.

   This draft is an exploration of, and recommendations for, timing of
   Resource Public Key Infrastructure publication, propagation, and use
   in relying party caches and routers.

   There are the questions of how frequently a CA publishes, how often
   an RP pulls, and how often routers pull from their RP(s).  Overall,
   the router(s) SHOULD react within an hour of to ROA publication.



Bush & Snijders         Expires October 23, 2020                [Page 2]


Internet-Draft               RPKI ROV Timing                  April 2020


   For CAs publishing, a few seconds to a minute seems easily achieved
   with reasonable software.  See Section 4.

   Relying Party validating caches periodically retrieve data from CA
   publication points..  RPs using rcynic to poll publication points
   every ten minutes would be a burden today, given the load it will put
   on publication services, and one notorious repository which is
   against specification.  But RPs using RRDP impose no such load.  So
   as the infrastructure moves from rcynic to RRDP, fetching every ten
   minutes would be reasonable.  For rcynic, an hour would be the
   longest acceptable window.  See Section 5.

   For the BGP speaking router(s) pulling from the RP(s), five minutes
   to an hour is a wide window.  But, the RPKI-Rtr protocol does have
   the Serial Notify PDU, the equivalent of DNS Notify, where the cache
   tells the router that it has new data.  See Section 6.

   We discuss each of these in detail below.

2.  Related Work

   It is assumed that the reader understands BGP, [RFC4271], the RPKI
   [RFC6480], RPKI Manifests [RFC6486], Route Origin Authorizations
   (ROAs), [RFC6482], the RPKI Repository Delta Protocol (RRDP)
   [RFC8182], The Resource Public Key Infrastructure (RPKI) to Router
   Protocol [I-D.ietf-sidrops-8210bis], RPKI-based Prefix Validation,
   [RFC6811], and Origin Validation Clarifications, [RFC8481].

3.  Deployment Structure

   Deployment of the RPKI to reach routers has a three-level structure
   as follows:

   Cerification Authorities:  The authoritative data of the RPKI are
      published in a distributed set of servers, Certification
      Authorities, at the IANA, RIRs, NIRs, and ISPs (see [RFC6481]).

   Relying Parties:  Relying Parties are a local set of one or more
      collected and verified caches of RPKI data.  A Relying Party,
      e.g., router or other client, MUST have a trust relationship with,
      and a trusted transport channel to, any RP(s) it uses.

      Note that RPs can pull from other RPs, thereby creating a somewhat
      complex topology.

   Routers:  A router fetches data from a local cache using the RPKI to
      Router Protocol described in [I-D.ietf-sidrops-8210bis].  It is
      said to be a client of the cache.  There are mechanisms for the



Bush & Snijders         Expires October 23, 2020                [Page 3]


Internet-Draft               RPKI ROV Timing                  April 2020


      router to assure itself of the authenticity of the cache and to
      authenticate itself to the cache.

4.  Certification Authority Publishing

   A principal constraint on publication timing is ensuring the CRL and
   Manifest ([RFC6486]) are atomically correct with respect to the other
   repository data.  With rcynic, the directory must be atomically
   correct before it becomes current.  RRDP ([RFC8182]) is similar, the
   directory must be atomically correct before it is published.

5.  Replying Party Fetching

   rcynic puts a load on RPKI publication point servers.  Therefore
   relying party caches have been discouraged from fetching more
   frequently than on the order of an hour.  Times as long as a day were
   even suggested.  With RRDP ([RFC8182]), these constraints are no
   longer relevant.

   A number of timers are embedded in the X.509 RPKI data which should
   also be considered.  E.g., CRL publication commitments, expiration of
   EE certificates pointing to Manifests and the Manifests themselves.
   Some CA operators commonly indicate new CRL information should be
   available in the next 24 hours.  These 24-hour sliding timers,
   combined with fetching RPKI data once a day, cause needless
   brittleness in the face of transient network issues between the CA
   and RP.

6.  Router Updating

   The rate of change of ROA data can be estimated to remain small,
   maybe on the order of a few ROAs a minute, but with bursts.
   Therefore, the routers may update from the (presumed local) relying
   party cache(s) quite frequently.  Note that
   [I-D.ietf-sidrops-8210bis] recommends a polling interval of one hour.
   This conservative timing is because caches can send a Serial Notify
   PDU to tell routers when there are new data to be fetched.

   A router SHOULD respond with a Serial Query when it receives a Serial
   Notify from a cache.  If a router can not respond to a Serial Notify,
   then it MUST send a periodic Serial Query no less frequently than
   once an hour.

7.  Alternative Technologies

   Should the supply chain include components or technologies other than
   those in IETF documents, the end effect SHOULD be the same; the
   router(s) SHOULD react to invalid AS origins within the same overall



Bush & Snijders         Expires October 23, 2020                [Page 4]


Internet-Draft               RPKI ROV Timing                  April 2020


   time constraint, an hour at most from ROA creation at the CA
   publication point to effect in the router.

8.  Security Considerations

   Route Origin Validation is not a security protocol.  It is intended
   to catch operational errors, and is easily gamed and attacked.

9.  IANA Considerations

   None

10.  References

10.1.  Normative References

   [I-D.ietf-sidrops-8210bis]
              Bush, R. and R. Austein, "The Resource Public Key
              Infrastructure (RPKI) to Router Protocol, Version 2",
              draft-ietf-sidrops-8210bis-00 (work in progress), March
              2020.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,
              <https://www.rfc-editor.org/info/rfc4271>.

   [RFC6481]  Huston, G., Loomans, R., and G. Michaelson, "A Profile for
              Resource Certificate Repository Structure", RFC 6481,
              DOI 10.17487/RFC6481, February 2012,
              <https://www.rfc-editor.org/info/rfc6481>.

   [RFC6482]  Lepinski, M., Kent, S., and D. Kong, "A Profile for Route
              Origin Authorizations (ROAs)", RFC 6482,
              DOI 10.17487/RFC6482, February 2012,
              <https://www.rfc-editor.org/info/rfc6482>.

   [RFC6486]  Austein, R., Huston, G., Kent, S., and M. Lepinski,
              "Manifests for the Resource Public Key Infrastructure
              (RPKI)", RFC 6486, DOI 10.17487/RFC6486, February 2012,
              <https://www.rfc-editor.org/info/rfc6486>.





Bush & Snijders         Expires October 23, 2020                [Page 5]


Internet-Draft               RPKI ROV Timing                  April 2020


   [RFC6811]  Mohapatra, P., Scudder, J., Ward, D., Bush, R., and R.
              Austein, "BGP Prefix Origin Validation", RFC 6811,
              DOI 10.17487/RFC6811, January 2013,
              <https://www.rfc-editor.org/info/rfc6811>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8182]  Bruijnzeels, T., Muravskiy, O., Weber, B., and R. Austein,
              "The RPKI Repository Delta Protocol (RRDP)", RFC 8182,
              DOI 10.17487/RFC8182, July 2017,
              <https://www.rfc-editor.org/info/rfc8182>.

   [RFC8481]  Bush, R., "Clarifications to BGP Origin Validation Based
              on Resource Public Key Infrastructure (RPKI)", RFC 8481,
              DOI 10.17487/RFC8481, September 2018,
              <https://www.rfc-editor.org/info/rfc8481>.

10.2.  Informative References

   [RFC6480]  Lepinski, M. and S. Kent, "An Infrastructure to Support
              Secure Internet Routing", RFC 6480, DOI 10.17487/RFC6480,
              February 2012, <https://www.rfc-editor.org/info/rfc6480>.

Appendix A.  Acknowledgements

   The authors wish to thank Massimiliano Stucchi.

Authors' Addresses

   Randy Bush
   Internet Initiative Japan & Arrcus, Inc.
   5147 Crystal Springs
   Bainbridge Island, Washington  98110
   United States of America

   Email: randy@psg.com


   Job Snijders
   NTT Ltd.
   Theodorus Majofskistraat 100
   Amsterdam  1065 SZ
   The Netherlands

   Email: job@ntt.net




Bush & Snijders         Expires October 23, 2020                [Page 6]