Skip to main content

RPKI Autonomous Systems Cones: A Profile To Define Sets of Autonomous Systems Numbers To Facilitate BGP Filtering
draft-ietf-grow-rpki-as-cones-00

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft whose latest revision state is "Expired".
Authors Job Snijders , Massimiliano Stucchi
Last updated 2018-09-07
Replaces draft-ss-grow-rpki-as-cones
RFC stream Internet Engineering Task Force (IETF)
Formats
Additional resources Mailing list discussion
Stream WG state WG Document
Document shepherd (None)
IESG IESG state I-D Exists
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD (None)
Send notices to (None)
draft-ietf-grow-rpki-as-cones-00
Global Routing Operations                                    J. Snijders
Internet-Draft                                                       NTT
Intended status: Informational                                M. Stucchi
Expires: March 11, 2019                                         RIPE NCC
                                                       September 7, 2018

 RPKI Autonomous Systems Cones: A Profile To Define Sets of Autonomous
              Systems Numbers To Facilitate BGP Filtering
                    draft-ietf-grow-rpki-as-cones-00

Abstract

   This document describes a way to define groups of Autonomous System
   numbers in RPKI [RFC6480].  We call them AS-Cones.  AS-Cones provide
   a mechanism to be used by operators for filtering BGP-4 [RFC4271]
   announcements.

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 March 11, 2019.

Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

Snijders & Stucchi       Expires March 11, 2019                 [Page 1]
Internet-Draft                RPKI AS Cones               September 2018

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (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.  Format of AS-Cone objects . . . . . . . . . . . . . . . . . .   3
     2.1.  Policy definition object  . . . . . . . . . . . . . . . .   3
       2.1.1.  Naming convention for Policy definition objects . . .   3
       2.1.2.  ASN.1 format of a Policy Definition object  . . . . .   3
       2.1.3.  Naming convention for neighbour relationships . . . .   4
     2.2.  AS-Cone definition object . . . . . . . . . . . . . . . .   4
       2.2.1.  Naming convention for AS-Cone objects . . . . . . . .   4
       2.2.2.  ASN.1 format of an AS-Cone  . . . . . . . . . . . . .   5
   3.  Validating an AS-Cone . . . . . . . . . . . . . . . . . . . .   5
   4.  Recommendations for use of AS-Cones at Internet Exchange
       points  . . . . . . . . . . . . . . . . . . . . . . . . . . .   6
   5.  Publication of AS-Cones as IRR objects  . . . . . . . . . . .   7
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
   8.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .   7
   9.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   7
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     10.1.  Normative References . . . . . . . . . . . . . . . . . .   7
     10.2.  Informative References . . . . . . . . . . . . . . . . .   8
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   8

1.  Introduction

   The main goal of the Resource Public Key Infrastructure (RPKI) system
   [RFC6480] is to support improved security for the global routing
   system.  This is achieved through the use of information stored in a
   distributed repository system comprised of signed objects.  A
   commonly used object type is the Route Object Authorisation (ROAs),
   which describe the prefixes originated by ASNs.

   There is however no way for an operator to assert the routes for its
   customer networks, making it difficult to use the information carried
   by RPKI to create meaningful BGP-4 filters without relying on RPSL
   [RFC2622] as-sets.

Snijders & Stucchi       Expires March 11, 2019                 [Page 2]
Internet-Draft                RPKI AS Cones               September 2018

   This memo introduces a new attestation object, called an AS-Cone.  An
   AS-Cone is a digitally signed object with the goal to enable
   operators to define a set of customers that can be found as "right
   adjacencies", or transit customer networks, facilitating the
   construction of prefix filters for a given ASN, thus making routing
   more secure.

2.  Format of AS-Cone objects

   AS-Cones are composed of two types of distinct objects:

   o  Policy definitions; and

   o  The AS-Cones themselves.

   These objects are stored in ASN.1 format and are digitally signed
   according to the same rules and conventions applied for RPKI ROA
   Objects ([RFC6482]).

2.1.  Policy definition object

   A policy definition contains a list the upstream and peering
   relationships for a given Autonomous System that need an AS-Cone to
   be used for filtering.  For each relationship, an AS-Cone is
   referenced to indicate which BGP networks will be announced to the
   other end of the relationship.

   The default behaviour for a neighbour, if the relationship is not
   explicitly described in the policy, is to only accept the networks
   originated by the ASN.  This means that a stub ASN neither has to set
   up any AS-Cone, description, nor policy.

   Only one AS-Cone can be supplied for a given relationship.  If more
   than one AS-Cone needs to be announced in the relationship, then it
   is mandatory to create a third AS-Cone that includes those two.

2.1.1.  Naming convention for Policy definition objects

   A Policy object is referenced using the Autonomous System number it
   refers to, preceded by the string "AS".

2.1.2.  ASN.1 format of a Policy Definition object

Snijders & Stucchi       Expires March 11, 2019                 [Page 3]
Internet-Draft                RPKI AS Cones               September 2018

   ASNPolicy DEFINITIONS ::=
   BEGIN
   Neighbours ::= SEQUENCE OF Neighbour

   Neighbour ::= SEQUENCE
   {
       ASN INTEGER (1..42949672965),
       ASCone  VisibleString
   }

   Version ::= INTEGER
   LastModified ::= GeneralizedTime
   Created ::= GeneralizedTime
   END

                ASN.1 format of a Policy definition object

2.1.3.  Naming convention for neighbour relationships

   When referring to a neighbour relationship contained in a Policy
   definition object the following convention should be used:

   ASX:ASY

   Where X is the number of the AS holder and Y is the number of the ASN
   intended to use the AS-Cone object to generate a filter.

2.2.  AS-Cone definition object

   An AS-Cone contains a list of the downstream customers and AS-Cones
   of a given ASN.  The list is used to create filter lists by the
   networks providing transit or a peering relationship with the ASN.

   An AS-Cone can reference another AS-Cone if a customer of the
   operator also has defined an AS-Cone to be announced upstream.

2.2.1.  Naming convention for AS-Cone objects

   AS-Cones MUST have a unique name for the ASN they belong to.  Names
   are composed of ASCII strings up to 255 characters long and cannot
   contain spaces.

   In order for AS-Cones to be unique in the global routing system,
   their string name is preceded by the AS number of the ASN they are
   part of, followed by ":".  For example, AS-Cone "EuropeanCustomers"
   for ASN 65530 is represented as "AS65530:EuropeanCustomers" when
   referenced from a third party.

Snijders & Stucchi       Expires March 11, 2019                 [Page 4]
Internet-Draft                RPKI AS Cones               September 2018

2.2.2.  ASN.1 format of an AS-Cone

   ASCone DEFINITIONS ::=
   BEGIN
   Entities ::= SEQUENCE OF Entity

   Entity CHOICE
   {
       ASN INTEGER (1..4294967295),
       OtherASCone VisibleString
   }

   Version ::= INTEGER
   LastModified ::= GeneralizedTime
   Created ::= GeneralizedTime
   END

                        ASN.1 format of an AS-Cone

3.  Validating an AS-Cone

   The goal of AS-Cones is to be able to recursively define all the
   originating ASNs that define the customer base of a given ASN,
   including all the transit relationships.  This means that through AS-
   Cones, it is possible to create a graph of all the neighbour
   relationships for the customers of a given ASN.

   In order to validate a full AS-Cone, a network operator MUST have
   access to the validated cache of an RPKI validator software
   containing all the Policy definition and AS-Cone objects.  Validation
   occurs following the description in: [RFC6488].

   In order to validate a full AS-Cone, an operator SHOULD perform the
   following steps:

   1.  For Every downstream ASN, the operator takes its policy
       definition file and collects a list of ASNs for the cone by
       looking at the following data, in exact order:

       1.  A policy for the specific relationship, in the form of
           ASX:ASY, where ASX is the downstream ASN, and ASY is the ASN
           of the operator validating the AS-Cone;

       2.  If there is no specific definition for the relationship, the
           ASX:Default policy;

Snijders & Stucchi       Expires March 11, 2019                 [Page 5]
Internet-Draft                RPKI AS Cones               September 2018

       If none of the two objects above exists, then the operator should
       only consider the ASN of its downstream to be added to the list.

   2.  These objects can either point to:

       1.  An AS-Cone; or

       2.  An ASN

   3.  If the definition points to an AS-Cone, the operator looks for
       the object referenced, which should be contained in the validated
       cache;

   4.  If the validated cache does not contain the referenced object,
       then the validation moves on to the next downstream network;

   5.  If the validated cache contains the referenced object, the
       validation process evaluates every entry in the AS-Cone.  For
       each entry:

       1.  If there is a reference to an ASN, then the operator adds the
           ASN to the list for the given AS-Cone;

       2.  If there is a reference to another AS-Cone, the validating
           process should recursively process all the entries in that
           AS-Cone first, with the same principles contained in this
           list.

       Since the goal is to build a list of ASNs announcing routes in
       the AS-Cone, then if an ASN or an AS-Cone are referenced more
       than once in the process, their contents should only be added
       once to the list.  This is intended to avoid endless loops, and
       in order to avoid cross-reference of AS-Cones

   6.  When all the AS-Cones referenced in the policies have been
       recursively iterated, and all the originating ASNs have been
       taken into account, the operator can then build a full prefix-
       list with all the prefixes originated in its AS-Cone.  This can
       be done by querying the RPKI validator software for all the
       networks originated by every ASN referenced in the AS-Cone.

4.  Recommendations for use of AS-Cones at Internet Exchange points

   When an operator is a member of an internet exchange point, it is
   recommended for it to create at least a Default policy.

   In case of a peering session with a route server, the operator could
   publish a policy pointing to the ASN of the route server.  A route

Snijders & Stucchi       Expires March 11, 2019                 [Page 6]
Internet-Draft                RPKI AS Cones               September 2018

   server operator, then, could build strict prefix filtering rules for
   all the participants, and offer it as a service to its members.

5.  Publication of AS-Cones as IRR objects

   AS-Cones are very similar to AS-Set RPSL Objects, so they could also
   be published in IRR Databases as AS-Set objects.  Every ASN contained
   in an AS-Cone, and all the AS-Cones referenced should be considered
   as member: attributes.  The naming convention for AS-Cones (ASX:AS-
   Cone) should be maintained, in order to keep consistency between the
   two databases.

6.  Security Considerations

   TBW

7.  IANA Considerations

   This memo includes no request to IANA.

8.  Contributors

   The following people contributed significantly to the content of the
   document: Greg Skinner.

9.  Acknowledgments

   The authors would like to thank ...

10.  References

10.1.  Normative References

   [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>.

   [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>.

Snijders & Stucchi       Expires March 11, 2019                 [Page 7]
Internet-Draft                RPKI AS Cones               September 2018

10.2.  Informative References

   [RFC2622]  Alaettinoglu, C., Villamizar, C., Gerich, E., Kessens, D.,
              Meyer, D., Bates, T., Karrenberg, D., and M. Terpstra,
              "Routing Policy Specification Language (RPSL)", RFC 2622,
              DOI 10.17487/RFC2622, June 1999,
              <https://www.rfc-editor.org/info/rfc2622>.

   [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>.

   [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>.

   [RFC6488]  Lepinski, M., Chi, A., and S. Kent, "Signed Object
              Template for the Resource Public Key Infrastructure
              (RPKI)", RFC 6488, DOI 10.17487/RFC6488, February 2012,
              <https://www.rfc-editor.org/info/rfc6488>.

Authors' Addresses

   Job Snijders
   NTT Communications
   Theodorus Majofskistraat 100
   Amsterdam  1065 SZ
   The Netherlands

   Email: job@ntt.net

   Massimiliano Stucchi
   RIPE NCC
   Stationsplein, 11
   Amsterdam  1012 AB
   The Netherlands

   Email: mstucchi@ripe.net

Snijders & Stucchi       Expires March 11, 2019                 [Page 8]