Internet Engineering Task Force (IETF)                  B. Haberman, Ed.
Request for Comments: 5943                                       JHU APL
Category: Standards Track                                    August 2010
ISSN: 2070-1721


A Dedicated Routing Policy Specification Language Interface Identifier
                       for Operational Testing

Abstract

  The deployment of new IP connectivity typically results in
  intermittent reachability for numerous reasons that are outside the
  scope of this document.  In order to aid in the debugging of these
  persistent problems, this document proposes the creation of a new
  Routing Policy Specification Language attribute that allows a network
  to advertise an IP address that is reachable and can be used as a
  target for diagnostic tests (e.g., pings).

Status of This Memo

  This is an Internet Standards Track document.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Further information on
  Internet Standards is available in Section 2 of RFC 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc5943.

Copyright Notice

  Copyright (c) 2010 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.




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RFC 5943                 RPSL Pingable Attribute             August 2010


Table of Contents

  1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . 2
  2.  RPSL Extension for Diagnostic Address . . . . . . . . . . . . . 2
  3.  Using the RPSL Pingable Attribute . . . . . . . . . . . . . . . 3
  4.  Security Considerations . . . . . . . . . . . . . . . . . . . . 3
  5.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . 4
  6.  Normative References  . . . . . . . . . . . . . . . . . . . . . 4

1.  Introduction

  The deployment of new IP connectivity typically results in
  intermittent reachability for numerous reasons that are outside the
  scope of this document.  In order to aid in the debugging of these
  persistent problems, this document proposes the creation of a new
  Routing Policy Specification Language attribute [RFC4012] that allows
  a network to advertise an IP address that is reachable and can be
  used as a target for diagnostic tests (e.g., pings).

  The goal of this diagnostic address is to provide operators a means
  to advertise selected hosts that can be targets of tests for such
  common issues as reachability and Path MTU discovery.

  The capitalized 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.  RPSL Extension for Diagnostic Address

  Network operators wishing to provide a diagnostic address for their
  peers, customers, etc., MAY advertise its existence via the Routing
  Policy Specification Language [RFC4012] [RFC2622].  The pingable
  attribute is a member of the route and route6 objects in the RPSL.
  The definition of the pingable attribute is shown in Figure 1.

  +-----------+-------------------+--------------+
  | Attribute |       Value       |    Type      |
  +-----------+-------------------+--------------+
  |  pingable | <ipv6-address> or |  optional,   |
  |           | <ipv4-address>    | multi-valued |
  +-----------+-------------------+--------------+
  |  ping-hdl |   <nic-handle>    |  optional,   |
  |           |                   | multi-valued |
  +-----------+-------------------+--------------+

               Figure 1: Pingable Attribute Specification




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RFC 5943                 RPSL Pingable Attribute             August 2010


  The exact definitions of <ipv4-address> and <nic-handle> can be found
  in [RFC2622], while the definition of <ipv6-address> is in [RFC4012].

  The pingable attribute allows a network operator to advertise an IP
  address of a node that should be reachable from outside networks.
  This node can be used as a destination address for diagnostic tests.
  The address specified MUST fall within the IP address range
  advertised in the route/route6 object containing the pingable
  attribute.  The ping-hdl provides a link to contact information for
  an entity capable of responding to queries concerning the specified
  IP address.  An example of using the pingable attribute is shown in
  Figure 2.

  route6: 2001:DB8::/32
  origin: AS64500
  pingable: 2001:DB8::DEAD:BEEF
  ping-hdl: OPS4-RIPE

                  Figure 2: Pingable Attribute Example

3.  Using the RPSL Pingable Attribute

  The presence of one or more pingable attributes signals to network
  operators that the operator of the target network is providing the
  address(es) for external diagnostic testing.  Tests involving the
  advertised address(es) SHOULD be rate limited to no more than ten
  probes in a five-minute window unless prior arrangements are made
  with the maintainer of the attribute.

4.  Security Considerations

  The use of routing registries based on RPSL requires a significant
  level of security.  In-depth discussion of the authentication and
  authorization capabilities and weaknesses within RPSL is in
  [RFC2725].  The application of authentication in RPSL is key
  considering the vulnerabilities that may arise from the abuse of the
  pingable attribute by nefarious actors.  Additional RPSL security
  issues are discussed in the Security Considerations sections of
  [RFC2622] and [RFC4012].

  The publication of this attribute only explicitly signals the
  availability of an ICMP Echo Request/Echo Response service on the
  specified IP address.  The operator, at his/her discretion, MAY
  deploy other services at the same IP address.  These services may be
  impacted by the ping service, given its publicity via the RPSL.






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RFC 5943                 RPSL Pingable Attribute             August 2010


  While this document specifies that external users of the pingable
  attribute rate limit their probes, there is no guarantee that they
  will do so.  Operators publicizing a pingable attribute are
  encouraged to deploy their own rate limiting for the advertised IP
  address in order to reduce the risk of a denial-of-service attack.
  Services, protocols, and ports on the advertised IP address should be
  filtered if they are not intended for external users.

5.  Acknowledgements

  Randy Bush and David Farmer provided the original concept for the
  pingable attribute and useful comments on preliminary versions of
  this document.  Joe Abley provided comments that justified moving the
  attribute to the route/route6 object and the inclusion of a point of
  contact.  Larry Blunk, Tony Tauber, David Harrington, Nicolas
  Williams, Sean Turner, and Peter Saint-Andre provided useful comments
  to improve the document.

6.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

  [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,
             June 1999.

  [RFC2725]  Villamizar, C., Alaettinoglu, C., Meyer, D., and S.
             Murphy, "Routing Policy System Security", RFC 2725,
             December 1999.

  [RFC4012]  Blunk, L., Damas, J., Parent, F., and A. Robachevsky,
             "Routing Policy Specification Language next generation
             (RPSLng)", RFC 4012, March 2005.

Author's Address

  Brian Haberman (editor)
  Johns Hopkins University Applied Physics Lab
  11100 Johns Hopkins Road
  Laurel, MD  20723-6099
  US

  Phone: +1 443 778 1319
  EMail: [email protected]





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